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Just perusing the ARRL letter on rec.radio.info and the lead story was very interesting. It's about the ARRL objecting to the use of some 70cm frequencies for a commercial event. This paragraph in particular caught my eye: "The ARRL called the Miller Motorsports Park choice of channels 'completely inappropriate. The radio amateurs who are licensed to use these frequencies are under no obligation to either tolerate interference or to cease their own operation, regardless of the interference that might be suffered at any time' by Miller Motorsports." Just goes to show how things are different in the US to here in the UK. Over here we are only secondary users of the 70cm band (the primary user of just about everything above 2m is the Ministry of Defence) and so we have to put up with anything and everything, including car alarm keyfobs on 433.92 MHz as an example. We also only get 430-440 MHz rather than your 420-450. Even in the 2m band (144-146 not 144-148 MHz..!), of which we are primary users,we cannot claim protection from interference. Ah well..! 73 Ivor G6URP |
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On Sat, 03 May 2008 07:57:45 -0400, Ivor Jones wrote:
Just perusing the ARRL letter on rec.radio.info and the lead story was very interesting. It's about the ARRL objecting to the use of some 70cm frequencies for a commercial event. ..... Just goes to show how things are different in the US to here in the UK. Over here we are only secondary users of the 70cm band (the primary use r of just about everything above 2m is the Ministry of Defence) and so we have to put up with anything and everything, including car alarm keyfob s on 433.92 MHz as an example. We also only get 430-440 MHz rather than your 420-450. If I recall properly we're secondary to the military in that band as well. Indeed, 70cm repeater operators are learning that the hard way... as many repeaters are having to reduce power or even go QRT at the request of our military, to protect a radar system. But the motorsports folks have no regular authority in that band at all. I'm not sure I understand why they thought they needed amateur spectrum for that project. |
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Doug Smith W9WI wrote:
If I recall properly we're secondary to the military in that [70cm] band as well. Indeed, 70cm repeater operators are learning that the hard way... as many repeaters are having to reduce power or even go QRT at the request of our military, to protect a radar system. But the motorsports folks have no regular authority in that band at all. I'm not sure I understand why they thought they needed amateur spectrum for that project. The Pave/Paws system that is pushing some repeaters off 70cm predates the complaints by several decades, and I take the military's new attitude to be another nail in the coffin of ham radio's former "favorite son" status at the Pentagon. It used to be that we hams were a corps of operators who could be pressed into service quickly during a war or other crisis. Now, with Morse as deeply buried as its creators and military electronics too secret to be entrusted to soldiers and sailors who haven't been vetted for security clearances, we're yesterday's news in the E ring. We'll have to find another reason to justify the allocations we enjoy. It's going to be hard work, and not nearly as easy as learning Morse (not that that would help now). We're going to have to get better - in fact, much better - at public relations: the Red Cross and other disaster relief agencies have known the importance of image all along, but now hams have got to get in the game and advertise ourselves as an anlternative to traditional communications during hurricanes, floods, earthquakes, etc. Of course we've had this debate before. Older hams such as I feel that we followed the program and did what was expected of us, and now I resend being pushed aside in favor of a Federal Emergency Management Agency which is, to my jaundiced eye, proficient only at promising what others will have to deliver and claiming credit for what others have done. It's a cold, cruel world, and we must get better at telling the public and the their elected officials how much we do. Bill -- Bill Horne, W1AC (Remove QRM from my address for direct replies.) |
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Anyone with some level of technical knowledge might wonder why a billion dollar (boondoggle) "radar system" can't discriminate between a fixed, known "target" (like a repeater)and one that is moving, comes from over the horizon which might be something nasty? Sounds like some real shoddy engineering took place at taxpayer expense. I can think of 3 or 4 ways to remove false targets w/o loosing any system level accuracy or sensitivity. In fact, didn't they perfect that during the cold war? Gee... Thinking about it some. All Abdulah (or Ivan or whoever) needs to do is buy a 440 rig, an amp and a yagi and go out as a "rover"; 3 or 4 kW ERP down the bear's craw for a while then move. Sigh.... On Sat, 3 May 2008 23:16:09 EDT, Bill Horne wrote: Doug Smith W9WI wrote: If I recall properly we're secondary to the military in that [70cm] band as well. Indeed, 70cm repeater operators are learning that the hard way... as many repeaters are having to reduce power or even go QRT at the request of our military, to protect a radar system. But the motorsports folks have no regular authority in that band at all. I'm not sure I understand why they thought they needed amateur spectrum for that project. The Pave/Paws system that is pushing some repeaters off 70cm predates the complaints by several decades, and I take the military's new attitude to be another nail in the coffin of ham radio's former "favorite son" status at the Pentagon. It used to be that we hams were a corps of operators who could be pressed into service quickly during a war or other crisis. Now, with Morse as deeply buried as its creators and military electronics too secret to be entrusted to soldiers and sailors who haven't been vetted for security clearances, we're yesterday's news in the E ring. We'll have to find another reason to justify the allocations we enjoy. It's going to be hard work, and not nearly as easy as learning Morse (not that that would help now). We're going to have to get better - in fact, much better - at public relations: the Red Cross and other disaster relief agencies have known the importance of image all along, but now hams have got to get in the game and advertise ourselves as an anlternative to traditional communications during hurricanes, floods, earthquakes, etc. Of course we've had this debate before. Older hams such as I feel that we followed the program and did what was expected of us, and now I resend being pushed aside in favor of a Federal Emergency Management Agency which is, to my jaundiced eye, proficient only at promising what others will have to deliver and claiming credit for what others have done. It's a cold, cruel world, and we must get better at telling the public and the their elected officials how much we do. Bill |
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In article ,
Bill Powell wrote: Anyone with some level of technical knowledge might wonder why a billion dollar (boondoggle) "radar system" can't discriminate between a fixed, known "target" (like a repeater)and one that is moving, comes from over the horizon which might be something nasty? Sounds like some real shoddy engineering took place at taxpayer expense. I can think of 3 or 4 ways to remove false targets w/o loosing any system level accuracy or sensitivity. In fact, didn't they perfect that during the cold war? Take a look at this month's issue of CQ for a possible explanation of the problem. To sum it up briefly: PAVE PAWS is a phased-array radar system, with a large number of individual turnstile antennas on each side. During reception, the signals picked up by the various individual antennas are combined electrically/electronically, in ways which cause them to mix in-pase for signals coming from the desired direction and out-of-phase for other directions. Older-generation phased array antenna systems perform the phase shifting by switching individual phase shifters (delay lines or similar) in series with the feedlines from the individual antennas. The delayed signals are then combined and detected. If you want to point the beam in a different direction, you change all of the phase-shifter delays. The newer generation of phased-array radar systems actually digitizes the incoming signal at each antenna, and then does the linear mixing (addition/subtraction) entirely in the digital domain. Why the change? I gather that it allows for both a finer degree of control of the delays (allowing higher resolution in beam-pointing), and also allows multiple different delay-and-combine operations to be performed in parallel (just add banks of DSPs), allowing one to track multiple targets simultanously. The disadvantage of this new system (as stated in CQ): it has rather less ability to reject off-axis signals than the older delay-line method of phasing. In the delay-line system, off-axis interference would tend mix out-of-phase *before* it was detected, and would largely cancel out. In the new system, *every* individual antenna and digitizer receives the interfering signal at full strength - there's no phase cancellation in the analog domain. This would leave the newer systems at a significant disadvantage with regard to saturation and desensitization by strong off-axis signals. It's not so much a question of false targets appearing, I think, but a question of the system losing the ability to detect the real targets. The digigal method of doing phase-shifting and beamforming is faster and more precise than the switched-analog method, but apparently somewhat less robust in this regard. As Scotty said, "The more complicated they make the plumbing, the easier it is to plug up the drains." -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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Bill Powell wrote:
Anyone with some level of technical knowledge might wonder why a billion dollar (boondoggle) "radar system" can't discriminate between a fixed, known "target" (like a repeater)and one that is moving, comes from over the horizon which might be something nasty? Even weather radar can do that with drops of water. :-) -- 73, Cecil http://www.w5dxp.com |
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Bill Horne wrote on Sat 3 May 2008 under the thread 'Discussions' in
RRAM: The Pave/Paws system that is pushing some repeaters off 70cm predates the complaints by several decades, and I take the military's new attitude to be another nail in the coffin of ham radio's former "favorite son" status at the Pentagon. As a veteran of the US Army Signal Corps 1952 to 1960 and as an engineer who has been involved in DoD electronics during my civilian career, I've seen NO evidence that US amateur radio was ever in some "favorite son" status in the US military. It used to be that we hams were a corps of operators who could be pressed into service quickly during a war or other crisis. Perhaps this was true in 1941. It was NOT true in 1952 when I voluntarily entered US Army service (during the Korean War active phase), trained at the Signal School at Fort Monmouth, NJ, and subsequently assigned to long-distance, high-volume message traffic handling on a 24/7 basis at a Far East Command Hq station in Tokyo. I served in that assignment for three years, had access to documents and reports on communications within the military and queried many on the (then) modern methods of communications by radio. From the military point of view of 56 years ago, having an interest in radio or the more general electronics field is only important towards assignment in a particular military occupation specialty (still familiarly called 'MOS'). Knowing on-off keying CW skills via amateur radio MIGHT get one assigned to Field Radio school (then the only Army MOS actually requiring OOK CW skill). Field Radio MOS then involved using HF from a truck-transportable station that was also equipped with teleprinters; teleprinted messaging was the norm in the Korean War (active phase '50-'53). The MAJORITY of 'radio' communications back then, a half century ago, was by VOICE and that over line-of-sight ranges. Military radio plans in the field were already organized into three overlapping radio bands from high HF into low VHF, the bands subdivided for infantry-artillery-armor unit use. No one needed any morse code skills to operate those radios then. Indeed, it was more akin to one-way talking on a telephone, something that most civilians had already done in the 1950s. Now, with Morse as deeply buried as its creators and military electronics too secret to be entrusted to soldiers and sailors who haven't been vetted for security clearances, we're yesterday's news in the E ring. I have NOT seen any of that "burial" nor of the "secrecy" alleged to any Pentagon "ring" in my Army service nor in the many years that followed as a civilian working on DoD contracts involving communications. The "secrecy" is actually on a very low Confidential level, the lowest of the three classifications. As a matter of fact, most Army radios of a half century ago where NOT used by signal personnel nor did they ever require any sort of security classification; no more so than revealing ANY military information to the enemy on anything. I have no personal knowledge of what actually transpires in ANY "ring" of the Pentagon. I must depend on periodicals and documents published by defense electronics and electronics professional associations to yield such information. In those, and in archived copies of "Signal" (a quarterly of the Army Signal Corps, available new to signal personnel) there has been NO such statements of any "favoritism" expressed from a half century ago to today. SECRECY in communications is regularly carried out today by UNvetted "soldiers and sailors" using a variety of cryptologically embedded (but selectable) means within radios. The standard small-unit (battalion or below) field radio is the SINCGARS family operating 30 to 88 MHz. The first SINCGARS went operational in 1989, almost two decades ago. Over 300,000 R/Ts basic to the AN/PRC-119 man-pack transceiver have been built by ITT, Fort Wayne, IN. More are available in HTs built by other firms plus the contracts awarded to Harris Corporation for newer, smaller SINCGARS-compatible multi- band radios. All of that family have their coding set by a "hopset" entry (encryption key and frequency-hopping sequence settings) which IS controlled by a "vetted" signal officer. The actual coding method is digital, beginning with a pseudo-random sequence generator involving digital feedback of a digital shift register could be known by an unfriendly...but the permutations of possible keys is so large that it is impractical for them to carry around super- computers in the field to defeat the cryptology in time to be effective. Note: The electronics technology to do all that has been known (and most things published about it openly) for over three decades, some of it public for four decades. In short, today's US military CAN use very robust, secure codes to allow UNvetted military personnel to communicate. They have had the capability to do so for nearly two decades. PAVE PAWS has been around for decades. It is in the technology classification using multiple receivers to decrease the antenna beam width with an ability to enhance phase shifting of the incoming wavefront (allows other processing refinements of returns). Anyone can gather information on its general technological structure. Since it IS primary in its assigned operating frequency and IS part of National Defense, that National Defense ought to be considered primary by US citizens who wish to survive. Is a radio hobby more important than national survival? We'll have to find another reason to justify the allocations we enjoy. It's going to be hard work, and not nearly as easy as learning Morse (not that that would help now). We're going to have to get better - in fact, much better - at public relations: the Red Cross and other disaster relief agencies have known the importance of image all along, but now hams have got to get in the game and advertise ourselves as an anlternative to traditional communications during hurricanes, floods, earthquakes, etc. Please leave the morse code test issue OUT. That has been settled for US amateur radio by the FCC after much, much debate for too long a time. IMAGE for the general public MUST be aimed OUTSIDE of amateur radio publications. It cannot remain the insider topic WITHIN amateur radio groups or publications. If it is REALLY there then it could (and should) get out into the mainstream. Such emergency good works news just haven't gotten out to the general public. The public sees FCC issues as they affect broadcasting and cell phones in the national news. maybe something about business radio of public safety radio. Amateur radio news is not an important issue for such media. The public has rarely seen amateur radio communications during emergencies during national news...it HAS seen various National Guard units and local government agencies doing communications on the news, including FEMA equipment (going back to 1994 and the Northridge Earthquake in January with quickly-transported video message displays relayed by satellite for their own health-and-welfare messages seen in handwriting of senders and shown on local TV). I'm not going to comment on the Katrina hurricane situation. That involves many more NON-amateur radio policies among local and state agencies. The Katrina hurricane happened over two years ago and the USA has had more emergencies since then. Rehashing the Katrina situation does NO good in attempting to get the word out to the general public about amateur radio. If ham radio is really as good as some declare it, it should be worth national attention. It has gotten very little on the national news in the last half century. QED. One thing that should NOT continue is to keep thinking in the paradigms of pre-WWII 'radio' as is often presented in amateur radio magazines. Technology has gone through several plateau jumps of advancement since that long-ago time. Fantasies of some amateur radio licensees are still rooted to back then. Those are lost in the reality of today's radio capabilites and uses. The general public has its own fantasies and it is foolish to attempt trying to tell them other fantasies. Amateur radio is a HOBBY. Let's try to focus on that. Model vehicles are a hobby for others. The Academy of Model Aeronautics doesn't pretend to advance the state of the art of aviation but it was successful in lobbying for a hundred frequency channels for radio-control two decades ago. Consider that hobbyists are citizens and that the US government does listen to its citizens. Work from that basis. Leonard H. Anderson AF6AY (Life Member) |
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On Mon, 5 May 2008 11:34:06 EDT, Bert Hyman wrote:
(Bill Powell) wrote in : Sounds like some real shoddy engineering took place at taxpayer expense. I can think of 3 or 4 ways to remove false targets w/o loosing any system level accuracy or sensitivity. In fact, didn't they perfect that during the cold war? If I was trying to do real-time analysis of such weak signals with the goal of protecting the nation, I'd take advantage of every technical and legal option available to me to limit or remove the potential for interference from very strong local signal sources. Technical for sure but it appears that even technology available to the general public isn't in (effective) use. A known and fixed "target" in ANY digital processing system is very easily noted and then removed from the data stream. Legal resources? Sounds like the typical "When all else fails, blame the ham" excuse. Do you also object to the "National Radio Quiet Zone" in West Virginia? Absolutely not! And, all a ham has to do there is to coordinate in advance. They have MANY issues with RFI from non-ham sources to contend with there. Wonder if PAVEPAWS is going to start shutting down microwave ovens and wireless dog fences next? :-) Bp PS - No complaints w/ the government entity but w/ the contractor(s). |
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On May 3, 11:16�pm, Bill Horne wrote:
Doug Smith W9WI wrote: If I recall properly we're secondary to the military in that [70cm] band as well. But the motorsports folks have no regular authority in that band at all. I'm not sure I understand why they thought they needed amateur spectrum for that project. � They obviously don't understand what amateur radio is all about. The Pave/Paws system that is pushing some repeaters off 70cm predates the complaints by several decades, and I take the military's new attitude to be another nail in the coffin of ham radio's former "favorite son" status at the Pentagon. Maybe - or maybe not. Secondary status means no interference need be tolerated by the primary. There used to be a 50 watt limit on 420-450 MHz for amateurs due to the possibility of interference to radar. It used to be that we hams were a corps of operators who could be pressed into service quickly during a war or other crisis. That's still the case. But it doesn't mean that the primary users of a band have to put up with interference from secondary users. Now, with Morse as deeply buried as its creators and military electronics too secret to be entrusted to soldiers and sailors who haven't been vetted for security clearances, we're yesterday's news in the E ring. I'm not sure what you mean by "Morse as deeply buried as its creators". We hams continue to use Morse Code on the air - extensively, too! MARS is running Morse Code nets again, on an experimental basis. It's true that Morse Code has all but been eliminated by the US military for its own communications uses. That's no surprise, even though Morse Code was used extensively by the US military in both World Wars, Korea, and Vietnam. But that doesn't mean hams should stop using Morse Code. We'll have to find another reason to justify the allocations we enjoy. How about these: 1) Public service communications (not just in emergencies, but for events like parades, marathons, bike races, etc.) Remember the search for Space Shuttle debris a few years back? Amateurs provided communications for at least some search groups, and it turned out to be more useful and flexible than cell phones or other radio services. 2) Education in radio and electronics. Learn-by-doing, IOW. Recently, ARRL ran a homebrew contest to design a 40 meter CW/SSB transceiver that would use less than $50 in parts. Several entries met all the requirements, and a winner was recently announced. What better way to learn radio than by building an operating a homebrew station? 3) Historical preservation. We have museums, historic districts, etc., in other areas, why not in radio? We hams have shown that old and new technologies can coexist, and an active operation is so much better than a dry nonfunctional museum display. 4) Experimentation/wilderness area. Most of the rest of the radio spectrum is channelized, digitized, and carefully planned as to its users and uses. The amateur bands are like a wilderness area, without all the central planning and channelization, where operator skill and technical knowhow can try all sorts of new and old things. And where all citizens who can pass the basic tests for a license have access to lots of spectrum, modes, and activities. It's going to be hard work, and not nearly as easy as learning Morse (not that that would help now). Morse Code is still worth learning, IMHO. We're going to have to get better - in fact, much better - at public relations: the Red Cross and other disaster relief agencies have known the importance of image all along, but now hams have got to get in the game and advertise ourselves as an anlternative to traditional communications during hurricanes, floods, earthquakes, etc. Agreed - but also as a fun thing to do. Emergency and public service comms are just one part of what hams do. The key factor is that the "served agencies" want different things today in the way of communications. In some emergencies they won't need hams at all, in others they will really need amateurs to help out. But they're the customer, as it were. 73 de Jim, N2EY |
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On Sat, 3 May 2008 16:25:37 EDT, Doug Smith W9WI
wrote: But the motorsports folks have no regular authority in that band at all. I'm not sure I understand why they thought they needed amateur spectrum for that project. Because they probably bought cheap amateur equipment, opened it out, and then found out that there weren't any channels available in the 450-470 MHz band that they could get licenses and frequency coordination for. Several sports events did just that until they got caught. One of my "day jobs" is as frequency coordinator for systems in the 450 MHz band, and we run into this all the time. The Congress refuses to give the FCC the necessary funding to apprehend them, and the Justice Department refuses to prosecute what they claim is petty offenses. I've ranted about this before. I'm glad that Chris Imlay (ARRL General Counsel) got on this thing as hard as he did. We all owe a round of thanks to him. -- 73 de K2ASP - Phil Kane ARRL Volunteer Counsel email: k2asp [at] arrl [dot] net |
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On May 6, 5:12 am, "Ivor Jones" wrote:
, typed, for some strange, unexplained reason: : Secondary status means no interference need be : tolerated by the primary. I should have been more clear, and qualfied the above as "here in the USA" Not always, we're the primary users of 2m over here, but we can't complain about interference. : There used to be a 50 watt limit on 420-450 MHz for amateurs due to : the possibility of interference to radar. Don't recall we ever had that over here, but I may be wrong. It was a US restriction a long time ago. : : It used to be that we hams were a corps of operators who could : be pressed into service quickly during a war or other crisis. : : That's still the case. But it doesn't mean that the primary users of a : band have to put up with interference from secondary users. Ah, but who is the primary user..? Here it's the military. Amateurs have to put up with anything and everything. On all bands. Well, here in the USA amateurs are definitely the secondary users of 420-450 MHz. So while we can complain, we don't have the same "standing", as it were. 73 de Jim, N2EY |
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On May 4, 11:13 pm, Bill Powell wrote:
Anyone with some level of technical knowledge might wonder why a billion dollar (boondoggle) "radar system" can't discriminate between a fixed, known "target" (like a repeater)and one that is moving, comes from over the horizon which might be something nasty? I think the radar system can indeed discriminate. One problem, I think, may be this: Radar that uses a single antenna for both transmit and receive cannot "see behind" a reflecting obstacle, nor an interfering RF source. So the amateur repeater casts a "shadow" as it were. To make it more of a sporting course, the amateur signal is intermittent, and FM. Which may look like all kinds of things on the radar display. Sounds like some real shoddy engineering took place at taxpayer expense. Maybe, but probably not. Some things are fundamental limitations of the physics involved. I can think of 3 or 4 ways to remove false targets w/o loosing any system level accuracy or sensitivity. In fact, didn't they perfect that during the cold war? Of course the processing system may be able to be programmed to ignore the amateur repeater - which would make it the perfect place to hide something. Remember that the radar system in question is probably being used in roles it was not originally designed for. That's probably why the problem didn't show up before. For example, if the radar was meant to look for high-altitude intruders, things like ground clutter and RF sources below a few hundred feet could simply be ignored. If the system is now being adapted to look for low-altitude and water-bourne intruders, those RF sources become a big headache that the system wasn't designed to handle. Gee... Thinking about it some. All Abdulah (or Ivan or whoever) needs to do is buy a 440 rig, an amp and a yagi and go out as a "rover"; 3 or 4 kW ERP down the bear's craw for a while then move. Maybe. But the result would probably be just the opposite: firing up that setup would announce his exact bearing and altitude. IOW, announcing "HERE I AM" to the radar system. With no legitimate sources of RF in the area, and no "shadows" to hide behind, finding the intruder would be easier and faster. This sort of thing isn't new. When you don't know the exact threat, you try to plug every possible hole. Way back in WW2, the Allies spent a lot of time and expense developing receivers that had extremely low local-oscillator radiation. Only approved receivers could be used aboard Allied vessels. The concern was that enemy U-boats could detect and find Allied convoys by listening for the local-oscillator radiation. When you have dozens of ships all monitoring the same frequency using big antennas and unshielded receivers, the total LO radiation could be heard a long way off. And while radio silence could be maintained in a convoy most of the time, the receivers were needed for weather reports, U-boat warnings, distress calls and such. It turned out that the U-boats did not listen for the LO radiation after all. But this was not known until after the war. 73 de Jim, N2EY |
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On May 5, 8:04Â pm, wrote:
On May 3, 11:16�pm, Bill Horne wrote: It used to be that we hams were a corps of operators who could be pressed into service quickly during a war or other crisis. That's still the case. Incorrect. Amateur radio operating protocol is nothing like what is used in the US military. That "case" might have been valid prior to WWII but that time period was 67 and more years ago. Now, with Morse as deeply buried as its creators and military electronics too secret to be entrusted to soldiers and sailors who haven't been vetted for security clearances, we're yesterday's news in the E ring. I'm not sure what you mean by "Morse as deeply buried as its creators". I would suggest you borrow a 'communications receiver' that can tune in the HF spectrum OTHER than amateur radio band allocations. For one thing, the US military had all but abandoned morse code mode before 1953 for any mass-volume messaging connecting North America to military bases around the rest of the world. For another thing, the US military has abandoned HF for any mass- volume messaging and now uses secure military communications satellites, troposcatter, and the DSN (Digital Switched Network) for 24/7 communications. DSN has very robust security and is the major system of 'flash' alerts to land bases. Alerts for submarines (to listen to HF thru microwaves for the main message) are slow-speed encrypted data at VLF that can be received while submerged. The US military still keeps HF radios on a standby basis but only uses them for periodic operational checks. MARS is not a part of the daily US military messaging routine, although it is much closer to the use of operations protocol than amateurs. We hams continue to use Morse Code on the air - extensively, too! Please define "extensively" (with or without exclamation mark). No one has stated or implied that amateur use of morse code was not "extensive." In an unofficial poll at the ARRL website some time ago, #1 communications mode on amateur bands was voice. MARS is running Morse Code nets again, on an experimental basis. Military Affiliate Radio System mission was changed about five years ago to act in accord with other US government agencies to (ostensibly) link them together. Army MARS Hq is at Fort Huachuca, AZ, the same military base that houses the Army Military Intelligence training facilities. It's true that Morse Code has all but been eliminated by the US military for its own communications uses. That is not true. For routine tactical or strategic communications the US military has abandoned morse code. The M.I. school at Fort Huachuca still trains some in morse code signal intercept analysis but that is NOT communications per se. To attempt stating that SIGINT operations "use morse code" is like saying the Army still uses muskets and Revolutionary War uniforms because one Army unit in Washington, DC, has them for ceremonial duties. That's no surprise, even though Morse Code was used extensively by the US military in both World Wars, Korea, and Vietnam. Morse code was used "extensively" in World War ONE. In that 1914 to 1918 period voice communications was relegated to wireline communications circuits. Teleprinter circuits had already been established before the US entry into WWII, including its use on USN ships (see the 'SIGABA' descriptions on various websites for online encryption capability over teleprinter as early as 1940). As a soldier during and just after the Korean War, doing mass- volume communications via HF, I can assure you that morse code was NOT used for such communications about logistics or military planning plus (in a secondary basis) broadcasting news and 'health and welfare' messages carried for the Red Cross and other agencies to military members. The vast majority of communications carried on during the recognized active period of US involvement in Vietnam was voice and teleprinter. Like the Korean War, the Vietnam War was not a 'true' war yet service members were killed or wounded as a part of that actual warfare. During the prosecution of the Korean War, the US military routinely handled about a quarter million messages a month through military facilities. That was nearly doubled for the Vietnam War. Morse code communications MIGHT have been used in rare instances for both wars but its role was so minor as to be discounted compared to the MASS of messaging needed to maintain troops and equipment far from the USA. All of that military communications information is public and available to anyone who cares to look for it. I would suggest the U.S. Army Center For Military History as a starting point for very detailed historical accounts of the US Army since the Revolutionary War. But that doesn't mean hams should stop using Morse Code. NOBODY has said "hams should stop using" it. Please try to restrain generating another sub-thread about it. Please try to educate yourself about radio uses outside of amateur radio as described other than the ARRL publications or website. In order to EDUCATE THE PUBLIC, I would suggest channeling your promotion OUTSIDE of amateur radio venues. The general public and lawmakers don't much look into ham radio venues. AF6AY |
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On May 6, 12:54�am, Bill Horne wrote:
AF6AY wrote: As a veteran of the US Army Signal Corps 1952 to 1960 and as an engineer who has been involved in DoD electronics during my civilian career, I've seen NO evidence that US amateur radio was ever in some "favorite son" status in the US military. The ham who gave me my novice exam, WA1BGR (SK), had a 10 KW generator in his backyard that he received from Air Force surplus via MARS. Not your $2,000.00 toilet seat, to be sure, but certainly a step up from the equipment available to the average ham, especially in 1964 New Hampshire, where power failures were a regular event. Would you be more comfortable if I said "poor relation" instead? In 2004 electric power failures in western Washington state were a regular event. All rural homes in Kitsap County, WA, have fireplaces and stacks of wood outside for that...despite electric power rates there being among the lowest in the USA. The fact is that equipment and expertise flowed from the military to the hams who were willing to work for it. That couldn't have happened by accident, and I don't believe it was an accident that ham allocations in shortwave bands survived during the era before geostationary satellites, when there was pressure from other governments and from corporate users here to carve out larger portions for broadcasting or commercial use. It used to be that we hams were a corps of operators who could be pressed into service quickly during a war or other crisis. Perhaps this was true in 1941. �It was NOT true in 1952 when I voluntarily entered US Army service (during the Korean War active phase), trained at the Signal School at Fort Monmouth, NJ, and subsequently assigned to long-distance, high-volume message traffic handling on a 24/7 basis at a Far East Command Hq station in Tokyo. � Welcome Home. There is no need for sarcasm. I returned to the States in 1956. The active phase of the Korean War stopped in June of 1953. ['truce talks' continue to this day in Korea along the DMZ] The Vietnam War ended for the USA 35 years ago. I would reply to more of your message but Google doesn't like it or something. AF6AY |
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AF6AY typed, for some strange, unexplained reason: : On May 5, 8:04 pm, wrote: : On May 3, 11:16�pm, Bill Horne wrote: : : It used to be that we hams were a corps of operators who could : be pressed into service quickly during a war or other crisis. : : That's still the case. : : Incorrect. Amateur radio operating protocol is nothing like what : is used in the US military. [snip] Well, I seem to have sparked quite a debate..! However, a lot of it seems to have gone more than a little OT (which doesn't surprise me and is actually quite interesting, so don't consider it a moan..!) But.. what are the thoughts on my original point, that of the differences in attitude of the authorities in the US and UK about protection from interference from commercial operators using frequencies within the amateur bands..? It seems to me, unless I've misunderstood, that in the US you can still claim a certain degree of protection from other users, whereas here we can't. 73 Ivor G6URP |
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On May 6, 4:18�pm, Phil Kane wrote:
On Tue, 6 May 2008 14:05:11 EDT, wrote: I think the equipment flow was both an incentive for the volunteers and a recruiting tool. It certainly was better than simply scrapping older stuff, or getting a few pennies per pound in surplus. I am told by a ranking MARS member that the loan/giveaway program stopped many years ago. Well, it still existed when I became a ham in 1967. But that was quite a while ago... �We used to see a lot of military surplus gear on the market even up into the late 1950s - I remember the ARC-5 stuff that you and I got started with, and the surplus tank low-band FM receiver that I had for monitoring the Sheriff and the Highway Patrol before crystallized receivers and scanners became consumer items -- but that's all history now. I still have some ARC-5 stuff in working order, and lots of parts. A couple of LM frequency meters, and a couple of ME-297 VOMs. I got started with stuff a lot more basic than an ARC-5, too. At least here in Philly, WW2 surplus was common well into the 1970s. Fair Radio Sales, to name one mailorder place, was still selling WW2 surplus at low prices in that same timeframe. The N2EY library has some of their catalogs.... For example, the 1976 Fair Radio catalog lists the BC-457 and BC-458 at $14.95 each (new condition), and the R-23, R-25 and R-26 at prices from $15.95 to $22.95. Earlier catalogs have a much wider selection at much lower prices. �Post-Korean War stuff never hit the market. Not in the quantities of WW2 stuff, obviously. I think that one factor in the enormous amount of WW2 surplus was that American industry was pouring the stuff out in enormous quantities by 1945, building up for at least another year of full scale combat, when the war suddenly ended. That situation has not recurred since. --- A look in the 1994 Fair Radio catalog shows the following: Collins 490T1 (CU-1666) antenna coupler for 618T, $400 used AM-6155/GRT-22 RF power amplifier, 225-400 MHz, 50W output, $235 R-1051B/URR HF receiver, used, $750 RT-618C & AM-3007 HF transceiver set, $795 RT-749/ARC-109 UHF transceiver, 225-400 MHz, $495 RT-594/ARC-3A HF transceiver, $210 R-390A receiver prices from $135 to $330 (you get the idea - there's a lot more) So there must have been some path for some surplus to the US market, although except for a few things the prices would be a problem. I am told that what the military doesn't give/sell/loan to foreign governments and even our own National Guard is scrapped (i.e. crushed beyond usefulness) , no doubt due to the pressure of the equipment manufacturers (yes, there are still quite a few left in the USA) who are more than happy to sell new stuff to amateur and commercial users alike at listed prices. I have been told that a lot of stuff is scrapped rather than have it fall into the wrong hands. There was also the influence of well-known amateurs such as Gen. Curtis LeMay, Barry Goldwater, Art Collins and even Arthur Godfrey. Ah yes, the legendary Friday-night Poker School.... (I'm still a member of the SAC Memorial ARC, as are several others in this group). Excellent! I am delighted to hear that, but not surprised. Add K2ORS, aka "Shep" (though he used the name Parker on the ham bands) to the above list. 73 es tnx for the info Jim, N2EY |
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Bill Horne wrote on Tues 6 May 2008 00:54
... I don't believe it was an accident that ham allocations in shortwave bands survived during the era before geostationary satellites, when there was pressure from other governments and from corporate users here to carve out larger portions for broadcasting or commercial use. There is considerable history of frequency allocations available at the International Telecommunications Union (ITU) website. Some of it is free for download or perusing. The ITU-R handles largely civil radio allocations but also takes into account military uses. Mass-volume messaging just on HF bands by common carrier services were already established in the latter half of the 1930s. That is also explained in the 'Collins Sideband Book' by Bruene, Shoenike, and Pappenfus. The migration of mass-volume messaging from HF to microwaves via commsat and, later, high-speed optical fiber cable, were done to avoid the ionospheric disturbances common to HF. WARC-79 (World Administrative Radio Conference of 1979) yielded more bands to radio amateurs worldwide. There were some added expansions to 'SW BC' but, by bandwidth count, amateurs got more than broadcasters. The '40m interference' issue of broadcasters versus amateurs took until WRC-03 (World Radio Conference of 1953) to achieve a compromise that won't be complete for a few years from now. Broadcasters were granted new bands in HF at WRC-03. In the last four decades there have been MANY changes to HF use by many radio services...and FAR MORE above 30 MHz. The migration of common carrier radio services from HF provided more space for individual fixed radio communications on HF. There is still room for other radio services on HF but few want it. The international radio use of the spectrum above 30 MHz over the last half century has been so extensive it could fill a small book to contain its changes. Those who have access to the huge table of frequency allocations in Part 2, Title 47 C.F.R. over the years can infer what they want. It covers civil and government frequency allocations from 9 KHz to 300 GHz. The migration of common carrier services from HF took about a quarter century to complete. It didn't happen overnight. The number of slots on the geosynchronous orbit were filled over a decade ago. 'Shortwave' broadcasters like their migration to satellite relay because it relieves the outages occurring on HF as the ionosphere changed. That's unfortunate for SWLs who were accostumed to essentially free programming but is a definite improvement of the fading and other effects on purely HF paths. Successful tests of DRM (Digital Radio Mondial) have been going on for at least four years. Adoption of DRM as a standard 'SWBC' mode is delayed by such listeners not desiring to obtain DRM-compatible receivers. Technically this digital broadcasting scheme has worked out very well. So far there have been NO auctions established for US civil radio services below 30 MHz. The HF ham allocations can be said to be safe from takeover. Speculating on HF being gobbled up by capitalists is more fantasy than reality. Long-haul mass-messaging services have been increased by 'repeaterless' fiber optic cables (amplification pumping and signal reconditioning only required at land stations). One of the longest today is the double 4 GPS optical fiber carrying digital signals running from the UK through the Med, under the Indian Ocean, around southeast Asia, then north to Japan. At 10 bits per circuit, each 4 GBS path can carry 100,000 circuits simultaneously...and full-duplex at that. There are many of other optical fiber paths in the world, over land and under water. USA radio amateurs were denied a full band on 60m due to failure of proponents from recognizing that many fixed HF frequencies in-around that band had already occupied those spots for decades. USA hams got only five separated channels, each just big enough to carry one SSB voice channel. I see that as just poor planning by the ARRL who petitioned for it. HF on the EM spectrum has far fewer users (other than hams now than it did four decades ago. The US military uses it now for backup (with limited traffic handling) as a sort of last-resort contingency use. Of course, US hams use HF 'extensively.' For hobby purposes. It is NOT 'pioneering the [HF] airwaves' (that being done in the 20s and 30s) but some like to imagine they are doing that. AF6AY |
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Bill Horne wrote on Tues 6 May 2008 00:54
AF6AY wrote: I said we were a trained corps of "_operators_", not just CW operators. I know that military radios almost always use voice: I ran the Navy MARS station at Danang in 1971 and 1972. I got the job because I had a ham license and I was there, and the unit commander cared about what I could _do_, not what my MOS was. The Military Affiliate Radio System was never a part of the tactical or strategic radio communications effort/network/system within the US military since it began (under another name) in pre-WWII US Army. It was generally considered to be a Public Relations activity akin to Special Services functions such as the AFRS (later changed to AFRTS, Armed Forces Radio and Television Service) or the Special Service traveling sports teams. Those of us who did the 24/7 grunt work of keeping all units communicating with one another did not consider MARS to be 'great.' None of us 24/7 grunt communicators required any federal license to do our jobs. FWIW, CW still came in handy on a couple of occasions: when signals dropped too low for phone patches, I could slide the KWM-2A down to the ham band and operate "maritime mobile" on CW to get health-and-welfare traffic through. One occasion I remember involved a seaman with a pregnant wife who was headed home on emergency leave due to complications of some kind: I'll never forget the look on his face when I read him the reply to the "ARL Two, ARL Nineteen" priority message I had sent minutes before - "Your wife and newborn son both OK congratulations dad". FWIW, I can relate a similar tale. The 250-TTY torn-tape relay floor at ADA Control had many operators on each shift. Each was assigned a group of circuits. TTY tape was chadless, both punched and printed. Red Cross and other agencies got lowest priority handling after the start of the 'radio day' (about 2 AM local time). One TTY operator spotted a message to another on his shift. He showed the tape to his friend who was overjoyed at the news that he was now a newborn father. Red Cross people wanted to pass the message to recipient in person. New father blurted out "I already knew it." That sparked a lot of indignity to the officials who only thought of 'procedure' and 'order of things.' He was reported to his company commander. CO was caught in a bind, being good to his men but also having to play politics with higher officials. I did some mild pleading of his case, suggesting Company Punishment (similar to Captain's Mast in USN). CO caught the drift and, knowing I had been scheduled as CQ (Charge of Quarters) that night, remanded his 'punishment' to me to handle while on CQ. Newborn father was still feeling good despite being chewed out so his 'punishment' was largely to keep me from falling asleep while on the 5 PM to 8 AM next-day CQ period. NO MARS involvement there, none needed. BTW, a military purchased Collins KWM-2 is the AN/FRC-93 and is the commercial version with all crystals, not limited to amateur radio bands (of 1975). There's an FRC-93 TM on the Internet, PDF size of about 6 MB. I have one. It is essentially the technical manual written, produced by Collins. In three years of my assignment with ADA in the Army, there was only ONE day of a two-hour total radio blackout on HF in 1955. Minimum RF power output at ADA was 1 KW on HF. That is only 10 db higher than typical ham radio HF transmitters. All operations were 24 hours a day, 7 days a week, and remained that way until 1963 when Army downsizing had all ops transferred to USAF, equipment, sites and all. USAF gave it all up with sites, buildings given to the Japanese in 1978. That was 30 years ago. AF6AY |
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On May 6, 4:44�pm, "Ivor Jones" wrote:
, typed, for some strange, unexplained reason: : On May 6, 5:12 am, "Ivor Jones" wrote: : Not always, we're the primary users of 2m over here, : but we can't : complain about interference. Hold that thought... : Well, here in the USA amateurs are definitely the secondary : users of : 420-450 MHz. Personally I'd rather have, say, 1 MHz of worldwide-exclusive-amateur allocation than 2 MHz of shared bandspace. But that's a minor thing, really. The big problem here in the USA with regard to amateur bands is that our FCC tolerates too much RFI from unlicensed emitters. For example, plasma TVs and other consumer electronics are notorious RF noisemakers. The whole BPL controversy is a classic example of a bad engineering idea being pushed for the wrong reasons. There's lots more, but a lot of it boils down to lack of enforcement resources coupled with the idea that the RF spectrum doesn't need as much protection from noise pollution. Recently, there was a particular brand/model of flat screen TV that radiated significant RF on the emergency-locator frequency. That caused quite a bit of excitement.... : So while we can complain, we don't have the : same "standing", as it : were. Well of course we can complain, but nobody will take any notice..! "You want to complain? Look at these shoes; I've only had 'em three weeks and the heels are worn right through! If you complain, nothing happens, you might as well not bother....." 73 de Jim, N2EY |
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Bill Horne wrote on 6 May 2008:
Of course, Health and Welfare traffic isn't a military necessity, but only a fool would neglect the morale of his men, and it didn't matter to the CO that I knew CW or that I used SSB most of the time - what _mattered_ was that I knew about long-path propagation, about how important it was to scrape the corrosion off the coax connectors, and that I could get the job done. They don't teach anything about operating "maritime mobile" at Fort Monmouth. Fort Monmouth is the home of CECOM, the ARMY's Central Electonics COMmand. The US Army waterborne vehicles are limited to river- crossing large inflatables although some are sent to USN or USMC schools for landing craft, hovercraft training. The "AN/" in a military nomenclature stands for Army-Navy and has for 6 decades. Any soldier, sailor, or airman can operate an "AN/" equipment if so authorized. Land field communications equipment is usually built to withstand total submergence in water. That CAN happen on land. Rest assured that field radio and radio relay students at Fort Gordon, GA, (Camp Gordon in the 50s) DID learn about short- and long-path [RF] propagation...and how to keep coaxial connectors, indeed all connectors clean and workable...and MUCH more. NVIS techniques have been taught for three decades at Gordon, usually referred to as 'Nevis' as its familiar name. Fort Gordon has taught operation of the standard small-unit land radio for two decades, the AN/PRC-119 plus its mobile and fixed versions (same R/T), plus the airborne unit, the first of the SINCGARS family. SINCGARS compatible radios don't have frequency or band selectors in the usual sense. It has a touch-screen with display to enter both the code key and the frequency-hopping key as determined by the local signal officer. First operational in 1989, it was field tested in the First Gulf War, then used 'extensively' in the Second Gulf War plus Afghanistan. Digitized voice, digital data, selectable clear-channel or encrypted anywhere in the 30 to 88 MHz region. ITT Fort Wayne, IN, has made 300K+ of those and Harris Corporation now has contracts for more in a newer, smaller version. It is remarkably robust, especially in crypto mode, can be netted. Internal time base can be calibrated via GPS signals via an AN/PSN-11 'Plugger' by plugging it into a connector on its front panel. There are SINCGARS-compatible HTs now on duty in Iraq and Afghanistan. Well, I suppose anyone with a soldering gun could fix a KY-28 when the pins come off: but only a ham would know that he could get solder from the tube pins of a trashed PRC-25 and use a fire to heat up a knife for the job. It wasn't me, but I know it _was_ a ham that did it. The AN/PRC-25 was solid-state except for the single vacuum tube in the PA. AN/PRC-77 was its fully solid-state version. Both were VHF with channelized tuning (considered abhorent by a few hams) but turned out to be mainstays for Vietnam field radio use. Both are now obsolete. Having seen the innards of both up close and personal, there are plenty of places to obtain solder from it...if that was a real necessity. Jury-rigged repairs have been going on with ALL military land equipment since before WWII and not just by licensed radio amateurs. shrug I have no personal knowledge of what actually transpires in ANY "ring" of the Pentagon. I must depend on periodicals and documents published by defense electronics and electronics professional associations to yield such information. In those, and in archived copies of "Signal" (a quarterly of the Army Signal Corps, available new to signal personnel) there has been NO such statements of any "favoritism" expressed from a half century ago to today. PAVE PAWS has been around for decades. [snip] Since it IS primary in its assigned operating frequency and IS part of National Defense, that National Defense ought to be considered primary by US citizens who wish to survive. Is a radio hobby more important than national survival? It's at least as important as not allowing oneself to be swayed by jingoistic appeals to misplaced patriotism. Opponents to amateur radio use of anything could point (accurately) to "jingoistic" statements of "misplaced patriotism" towards the ARRL. shrug There are many sides to any issue. Ham Radio operators and equipment would be essential to keep life going. [after a nuclear holocaust] I've had one complete physical exam since getting my amateur radio license last March. My primary physician had detected no new super-human powers in my body. :-) That absolute statement is unprovable. Radio amateurs are as mortal as any other human being. As one who has seen electronic equipment developed for all possible 'radio' environments. Amateur radio gear is NOT close to rad-hardened military equipment. It is essentially consumer electronics grade although better than most consumer stuff. Only two ready-made HT radios (as I recall) are advertised as fully submersible. Boosters of amateur radio licensee qualities tend to forget that there are many, many more 'civilians' who are knowledgeable and proficient in radio communications equipment and techniques. Their numbers may be MORE than the total number of ham licensees in the USA. Licensed radio amateurs in the USA make up only about a quarter of one percent of the total population. ...Hams aren't just trained to pound brass: those that homebrew their own gear or compete in Field Day or participate in disaster-preparedness are trained to think on their feet, and that means they care about getting the job done, not the mode(s) they use to do it. That's a lovely thought, but misleading. Lots of 'civilians' are also able to "think on their feet" and do so regularly. Utility repairpersons reacting to large-scale damage repair are one such example that I've observed up-close and personal. My observation of 'Field Day' since its onset has been a radio contest carried out in a park on a nice day in June with picnic food. When QST had a two-page article on Field Day recipies, that pretty much wiped out any notion in my mind that Field Day was any 'emergency exercise.' AF6AY |
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AF6AY wrote:
On May 6, 12:54�am, Bill Horne wrote: It was NOT true in 1952 when I voluntarily entered US Army service (during the Korean War active phase), trained at the Signal School at Fort Monmouth, NJ, and subsequently assigned to long-distance, high-volume message traffic handling on a 24/7 basis at a Far East Command Hq station in Tokyo. Welcome Home. There is no need for sarcasm. None was intended: if you see my salute to your service as sarcasm, that's on you. Vietnam veterans have been using those words as a greeting ever since we came back: for a while, we were the only ones saying them. W1AC -- Bill Horne (Remove QRM from my address for direct replies.) |
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On May 7, 12:03�am, "Ivor Jones" wrote:
what are the thoughts on my original point, that of the differences in attitude of the authorities in the US and UK about protection from interference from commercial operators using frequencies within the amateur bands..? It seems to me, unless I've misunderstood, that in the US you can still claim a certain degree of protection from other users, whereas here we can't. The following is just an informal observation... Here in the USA, we have two regulatory agencies for radio: FCC, which does non-government radio, and NTIA, which does government/military radio. NTIA trumps FCC, of course. The radar-interference case mentioned elsewhere in this thread clearly shows who has priority on the band in question. But your question is about *commercial* (nongovernment) users/ intruders into the amateur bands, where such use is not part of the regulations. In theory, those intruders are breaking the law and should be removed by the FCC. In practice, the FCC is complaint-driven, which means amateurs must identify the intruder and complain to the FCC. Helping with such complaints is one of the major functions of the ARRL and its legal department. But simply complaining to FCC does not mean the problem will be solved, because FCC's resources are very limited. The motorsports story referred to required a lot of work on the part of the ARRL and the amateurs involved. 73 de Jim, N2EY |
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On May 5, 8:38�pm, AF6AY wrote:
One thing that should NOT continue is to keep thinking in the paradigms of pre-WWII 'radio' as is often presented in amateur radio magazines. What paradigms do you mean? �Technology has gone through several plateau jumps of advancement since that long-ago time. In some areas, that's true, but in others (such as simple practical HF antennas and transmission lines) things haven't changed very much. �Fantasies of some amateur radio licensees are still rooted to back then. �Those are lost in the reality of today's radio capabilites and uses. �The general public has its own fantasies and it is foolish to attempt trying to tell them other fantasies. Could you give some specific examples of the paradigms you mean, the "plateau jumps" in technology, and the fantasies you describe? Amateur radio is a HOBBY. �Let's try to focus on that. Amateur radio isn't *just* a hobby, though. The record of public service communication by radio amateurs shows there is a lot more to it, to give just one example. Model vehicles are a hobby for others. �The Academy of Model Aeronautics doesn't pretend to advance the state of the art of aviation but it was successful in lobbying for a hundred frequency channels for radio-control two decades ago. Let's consider that idea in detail... Model control radio frequencies consist of those 100 channels near 70 MHz. Power output is limited to 1 watt and the transmitting antenna can be no larger than a quarter-wave monopole. Model control isn't about using radio for its own sake, which IMHO is the heart-and-soul of amateur radio. Model control is about using radio for a single purpose, as a means to an end. Does anyone think amateur radio should be limited by rules similar to those for model control? Or that the kind of allocations given to model-control enthusiasts would be adequate for amateur radio? �Consider that hobbyists are citizens and that the US government does listen to its citizens. �Work from that basis. It seems to me that you are saying that radio amateurs should not talk about their roles in emergency communication (Hurricane Katrina, for example), public service communication (New York City Marathon), experimentation (K3TUP and cancer research), education (Space Shuttle hams), etc. IOW, all that should be deemphasized and ignored. It seems to me that you're saying we hams should define ourselves as hobbyists *only*, and expect that to be the sole reason we have amateur bands and FCC/ITU protection. Is that correct? Jim, N2EY |
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On Wed, 7 May 2008 00:06:21 EDT, AF6AY wrote:
The migration of mass-volume messaging from HF to microwaves via commsat and, later, high-speed optical fiber cable, were done to avoid the ionospheric disturbances common to HF. Actually, Len, the first "migration" was to the pre-fiber undersea cables. I was involved in moving Israel's circuits off HF onto the Haifa-Marseilles cable (and thence onto the TAT-5 cable) in 1967, several years before the parallel Intelsat satellite service was turned on. We had several ISB circuits to NY - double hop, mind you - and the rest of our circuits were HF to London, Paris, Athens, Moscow, and several other European cities and thence by landline and TAT-5 to the rest of the world. Of course, that all changed when Intelsat and the fiber cables came into service. -- 73 de K2ASP - Phil Kane From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon e-mail: k2asp [at] arrl [dot] net |
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On Wed, 7 May 2008 00:06:21 EDT, AF6AY wrote:
HF on the EM spectrum has far fewer users (other than hams now than it did four decades ago. The US military uses it now for backup (with limited traffic handling) as a sort of last-resort contingency use. Very much out of the spotlight, states and counties have been setting up HF networks on "commercial" frequencies for disaster relief, search and rescue, and other functions where VHF/UHF won't do. I'm involved with that here. This is in parallel with, not supplanting, the volunteer services that amateur operators are rendering on HF, VHF, and UHF through the ARES/RACES organizations. Not surprisingly, most of the career professional Emergency Communication managers of these governmental units are hams as well. -- 73 de K2ASP - Phil Kane From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon e-mail: k2asp [at] arrl [dot] net |
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On Wed, 7 May 2008 00:07:53 EDT, AF6AY wrote:
None of us 24/7 grunt communicators required any federal license to do our jobs. You've been saying that for years, Len. It's disingenuous at best. It's accurate to say that none of you had to have an _FCC_ license to do your job. In reality, the "Federal license" that was required was the assignment to your job by military superiors - who could yank you out of there for any reason, real or imagined, effectively 'canceling" that "license". At least the FCC has to hold a hearing at which you can defend yourself. -- 73 de K2ASP - Phil Kane From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon e-mail: k2asp [at] arrl [dot] net |
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On May 7, 9:02�pm, Phil Kane wrote:
On Wed, 7 May 2008 00:06:21 EDT, AF6AY wrote: The migration of mass-volume messaging from HF to microwaves via commsat and, later, high-speed optical fiber cable, were done to avoid the ionospheric disturbances common to HF. Actually, Len, the first "migration" was to the pre-fiber undersea cables. The first of which (TAT-1) became operational in 1956. Both the coaxial (copper) and fiber cables under the oceans require repeaters if their length exceeds 100 km or so. Some of the early undersea coaxial cables with their vacuum-tube repeaters are still functional, but their capacity is trivial compared to the fibers. �I was involved in moving Israel's circuits off HF onto the Haifa-Marseilles cable (and thence onto the TAT-5 cable) in 1967, several years before the parallel Intelsat satellite service was turned on. �We had several ISB circuits to NY - double hop, mind you - and the rest of our circuits were HF to London, Paris, Athens, Moscow, and several other European cities and thence by landline and TAT-5 to the rest of the world. Great story, Phil! Does any of that remain as a backup? My guess would be that it is long gone. From a capacity standpoint, satellites are the backup now in most places, because the fiber bandwidth is so much greater. It wasn't just ionospheric disturbance that pushed the change to satellites and cable, either. There's only so much useful HF spectrum, and the newer technologies offer many orders of magnitude greater bandwidth. �Of course, that all changed when Intelsat and the fiber cables came into service. And it continues to change. In this area, direct fiber-to-the-customer is becoming the standard; many homes here have no copper communications and little if any radio reception at all. Everything comes through the fiber - telephone (multiple lines if you want), highspeed internet, and TV. The fiber is RFI-and EMI-immune, too. The biggest headache they present for us hams is that sometimes the switching power supply for the customer equipment is electrically noisy. IMHO the real threat to Amateur Radio isn't the possible reallocation of the HF amateur bands to other services (although that's always a possibility, and VHF/UHF are not nearly so secure). The major threat today, I think, is that the bands we have - MF, HF, VHF and UHF - are slowly being made less-usable or even unusable by a combination of factors: 1) Lack of enforcement against intruders, such as unlicensed use of 10 meters by truckers and others, spreading out from 11 meters. This has been a problem since at least the 1970s. 2) Reduction in the number of housing units where a ham can have a reasonable antenna system. Boilerplate anti-antenna CC&Rs have been pretty standard since the 1970s in many areas, and once in place they are often impossible to remove. 3) Consumer electronics that are not adequately RFI proofed. 4) Consumer electronics and other devices that make excessive RF noise in the ham bands. As the number of such devices increases, the noise floor in many locations rises to unusable levels. 5) A regulatory environment where the above problems are simply not given any priority. (You know more about that than I, Phil!) 73 de Jim, N2EY (who had a small part in the installation of some overland fibers back in the '80s and '90s) |
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On Wed, 7 May 2008 00:10:29 EDT, AF6AY wrote: The AN/PRC-25 was solid-state except for the single vacuum tube in the PA. AN/PRC-77 was its fully solid-state version. Both were VHF with channelized tuning (considered abhorent by a few hams) but turned out to be mainstays for Vietnam field radio use. Both are now obsolete. And we will never see them on the commercial surplus market available to hams, like the WW-II stuff was decades earlier. -- 73 de K2ASP - Phil Kane From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon e-mail: k2asp [at] arrl [dot] net |
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On Wed, 7 May 2008 13:48:04 EDT, "Ivor Jones"
wrote: It's the principle of the thing that annoys me, though. Even where we are primary users, such as 2m, we can claim *no* protection from interference, even if the cause of said interference shouldn't be there. Things must have changed since my initial training in international radio regulation in the mid-1960s where the British Post Office (the forerunner of the RA) was held up as a model of "we'll lock you up if you don't have a licence to operate there" - and the French were pointed out as an example of "the ordinary citizen needs a radio as much as he needs a machine gun".....hams were a grudging exception, and of course when cellphones became available, everyone got one because they knew that cellphones were not radios, right? g Then again, the FCC in the US - where I ultimately spent most of my professional career - was also very involved in "catching bad guys". The epidemic of unlawful CB operations of the 1970s and 80s - for which most of the world's governments never forgave the US - and an unfortunate shift in regard to what the government's obligations were - changed all that. Notwithstanding the historical precedents of military-civilian sharing of frequency bands, granting commercial interests licenses to operate in the amateur bands is basic bad regulatory policy. All of us old-time regulation professionals knew that as an article of faith. The new crop is guided more by the buck (or the Euro, or the quid) than by what good regulatory policy is. As far as the military goes, I learned early in the game that de facto the military of any country can operate on any frequency that it so desires if (1) it doesn't interfere with anything operating in that country and it (2) doesn't identify. If it wants to play the gentleman game the country will notify the operation to the ITU Radiocommunications Bureau (ITU-R) which now does what the International Frequency Registration Bureau (IFRB) did before ITU reorganization. Whether the information is accurate or not is an exercise left for the listener. -- 73 de K2ASP - Phil Kane From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon e-mail: k2asp [at] arrl [dot] net |
Differences..!
Ah, thanks. However, over here we do have "legal" intrusions into some of
the amateur bands, most are in the microwave region, notably 10GHz, where we lost a sizeable chunk a while back. The main one though is 431-432 MHz which is not available for use within 100km of Charing Cross (central London) and also for some distance around the military radar installation at Fylingdales in Yorkshire. In the London area I believe it's allocated to taxis of all things..! There isn't a lot of amateur activity in that segment, I think some wide-split repeaters may have inputs or outputs there but generally it's a low-occupancy segment of the band, so all in all it's not a major hassle. It's the principle of the thing that annoys me, though. Even where we are primary users, such as 2m, we can claim *no* protection from interference, even if the cause of said interference shouldn't be there. 73 Ivor G6URP The main problem in the UK is not the commercial use of 431-432 in the London area, rather the proliferation of licence exempt low power devices. Everything from key fobs to weather stations and tower crane anti-collision systems. They are popping up quite legally all over 70cms. Even one 70cms repeater was ordered off the air because it was stopping people from remotely opening their car doors in a nearby carpark! The UK has a Pave Paws derivative at Fylingdales at that caused a ban on new repeater applications in 70cms, the military being worried about the increase in noise floor that additional signals would introduce. 73 Jeff |
Differences..!
In ,
Phil Kane typed, for some strange, unexplained reason: : On Wed, 7 May 2008 13:48:04 EDT, "Ivor Jones" : wrote: : : It's the principle of the thing that annoys me, though. Even where : we are primary users, such as 2m, we can claim *no* protection from : interference, even if the cause of said interference shouldn't be : there. : : Things must have changed since my initial training in international : radio regulation in the mid-1960s where the British Post Office (the : forerunner of the RA) was held up as a model of "we'll lock you up if : you don't have a licence to operate there" - and the French were : pointed out as an example of "the ordinary citizen needs a radio as : much as he needs a machine gun".....hams were a grudging exception, : and of course when cellphones became available, everyone got one : because they knew that cellphones were not radios, right? g Indeed. My friend Colin G3USA (great callsign, eh..!) tells me that in his early days on air in the 60's an amateur could expect to be regularly visited by an officer of the Radio Investigation Service who would check your logbook and that you knew how to use a wavemeter for example. In my 25 years of being licensed I've never been inspected once. 73 Ivor G6URP |
Differences..!
Phil Kane wrote:
On Wed, 7 May 2008 00:10:29 EDT, AF6AY wrote: The AN/PRC-25 was solid-state except for the single vacuum tube in the PA. AN/PRC-77 was its fully solid-state version. Both were VHF with channelized tuning (considered abhorent by a few hams) but turned out to be mainstays for Vietnam field radio use. Both are now obsolete. And we will never see them on the commercial surplus market available to hams, like the WW-II stuff was decades earlier. If I had been asked to make a choice of whether they _should_ be available, I'd probably have shaken my head sadly and said "No". Given that the PRC-25 covered not only the Low-VHF public safety bands and some TV frequencies, but also the aircraft marker-beacon channel, as well as six meters, I'd have to (reluctantly) agree with whomever else said "No" in this case. It's a shame, but it's also easy to understand: the FCC was _very_ badly burned by the Citizen's Band fiasco, and I'd bet other government bureaucrats in and out of the military had that fresh in their minds as Vietnam was winding down and the PRC-25's were filling up warehouses. 73, Bill W1AC -- Bill Horne (Remove QRM from my address for direct replies.) |
Differences..!
Bill Horne wrote:
Phil Kane wrote: And we will never see them on the commercial surplus market available to hams, like the WW-II stuff was decades earlier. It's a shame, but it's also easy to understand: the FCC was _very_ badly burned by the Citizen's Band fiasco, and I'd bet other government bureaucrats in and out of the military had that fresh in their minds as Vietnam was winding down and the PRC-25's were filling up warehouses. It's really more simple than that actually. At the end of World War Two, every one thought, "Well, that's the end of that. There will NEVER be another war now." The military planners were looking at another 8 years of combat in the Pacific and on the island of Japan to bring a conclusion to World War Two. When the second atomic bomb was dropped, Japan threw in the towel and quit. With the rather sudden end of the war with Japan, that left stocks for the planned additional 8 years of warfare with no place to use it. So there really was more "war surplus" stuff available at the end of World War Two. Most of the equipment used in Europe was left behind or just thrown off of ships etc rather than bring it back. Or we would still be seeing equipment for sale. By the time Vietnam was over, the military, having found themselves fighting an enemy that didn't have any problems using our own equipment, they decided "No, that's not gonna happen again" and the move towards "demilitarizing" equipment rather than just auctioning it off by the pallet, or disposing it like the last time around. Jeff-1.0 wa6fwi |
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