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#1
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From: Paul Keinanen on Sun,May 8 2005 11:54 pm
On Sun, 08 May 2005 10:44:27 -0700, Tim Wescott wrote: The basic difference is that with a digital system you either end up with a clean signal or a useless signal. In an analog system the character and purity of the signal must be carefully guarded, at least until you manage to digitize it. This means that there will be a much greater chance that adding a new card to the radio will degrade not only the function of the new card, but the function of all the other cards. Second, the PC market is a huge one, with great advantages to be derived from common equipment and software, and much smaller advantages to be derived from commonality. This is the exact obverse of the radio market, including homebrew radios. To make a "card" radio would be to define a basic radio architecture, probably down to the IF frequency (or at least to the point of forcing you to match your IF and front end). While improvements could be made within this structure an independent experimenter couldn't play around with such things as direct-conversion, different IF schemes, etc., without extensive modification. I agree that it would be quite hard to make a good quality radio with some common backplane structure. However, connecting various functional modules with 50 ohm input and output impedance could be used to make quite different radios with good specifications. That's already been done in the RF industry for a half century. As one example, take the U.S.' AN/PRC-8, -9, -10 series of manpack transceivers covering high-HF into low-VHF. Still in the vacuum tube era, all of the IF modules included the IF tuned circuits as well as the subminiature tube. If the tube filament burned out, the entire module was replaced. NO alignment tweaking was required. Design was done back around 1950. As for standards on control...start with the ATLAS (for USAF test equipment) and continue on to the IEEE-488 interface. Those standards worked with "modular" components capable of testing receiver sensitivity down to noise level with KNOWN signal levels. By the way, test equipment for RF has been standardized at 50 Ohms since WW2 days. For instance Mini-Circuits also makes various diode ring mixers, amplifiers and apparently also VCOs that are boxed and have BNC or SMA connectors. With each functional module in a metallic enclosure, controlling the spurious radiation between modules is much easier. I don't know that anyone would make filter modules, which would be required to build a complete radio. Also SSB-Electronics sold separate amplifier, mixer, frequency multiplier and crystal oscillator modules mainly intended for a 10 GHz transverter. Unfortunately the cost of these modules is quite high, apparently due to low production volumes and large amount of manual labour needed to assemble them. If there would be a large demand for such modules, it would make sense to design them to require less manual labour to assemble them and hence get the price to more affordable levels. Define "more affordable." :-) "Filter modules" have and are built to order by dozens (if not hundreds worldwide) of companies. The costs ARE high because they are built TO specifications and such have to be TESTED to meet those specifications. Is there comparable KNOWN/calibrated test equipment in the average homebrewer's hobby workshop that is comparable...even at "low" frequencies of HF? Actually, Kaylie's Mini-circuits DOES use calibrated, automatic test equipment to check out each module, small quantities to large quantities. Mini-Circuits doesn't have the market demand to do production runs in the 10,000-lot quantities. The mystique on L-C filters is largely that...mystique. Without some good, calibrated test equipment, it is very difficult to determine what a "filter module" has for performance. Synthesis (design) of the values for a particular filter type was arduous until folks came out with computer-aided design. I have a working freeware program for PCs on that...send a message in private e-mail if you want one transmitted to you. As to cost, just look at a cellular telephone handset. Those can cost around US$ 50 each, new. They work in a band roughly centered at 1.0 GHz. Microwaves. Complete microwave Rx-Tx with synthesized tuning. For half a hundred US dollars here. A mere 30 years ago that would be almost inconceivable. Three years ago the U.S. Census Bureau said that one in three Americans have a cell phone subscription. That's roughly 100 MILLION units either out there or waiting to be used. Market quantity and competition in that market are the key to bringing down costs. Radio hobbyists just cannot possibly get close to such market quantities. While a backplane would not be suitable for running the RF signals, it would be a good idea to have a common control interface standard. This might be some sort of serial interface or perhaps a CANbus interface as used on some AMSAT satellites. Who says a "backplane would not be suitable?" :-) Those PC backplanes carry terribly broad spectra of RF...from (literally) DC on up to the low microwaves. No "perhaps" about it. Thing is, the layout can NOT be done as if it were wire-wrap; i.e., in random order of wire placement. With broadbanding anything, every single adjacent trace becomes a COUPLER and unwitting layouts can produce remarkable crosstalk effects. Designers have known that for decades and handle it...all kinds of Application Notes and info out in public access available for anyone...just too specialized for the "weekender" small-project assembler hobbyist. The IEEE-488 is a mature standard for control and interface for computer-controlled, interconnected systems. Would be a bit TOO all-inclusive for a special-purpose new design. The "interface" does NOT have to be some kind of "new" thing used on the latest whatever out in space. It's just a control- and-response avenue carrying signals of a standardized kind...a few wires/traces perhaps...laid out properly if required to be broadbanded or broad in dynamic signal range. Not a big thing, but needs some THOUGHT before becoming hardware. |
#2
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I don't think much of the discussion has looked very closely at what I
think is envisioned here -- a mainframe which would accept various "cards" from numerous vendors. As I detailed in an earlier posting, it's tough enough (and costly) to make a robust interface when a single company has full control of the mainframe and plugins. But let's think a little about the problems of making a mainframe which could accommodate cards from various vendors -- cards which have different performance characteristics. The first question is, who will define the interface? Who will dictate modifications as they become necessary? Then let's consider a vendor who wants to make, say, an audio amplifier card. It has digital signal processing with a dozen different modes. Each mode has considerable adjustment range, for example the width of a bandpass filter. The interface would have to have pins dedicated to these functions, and the front panel would have to have switches and controls for them. How about an oscillator? One might be digitally tuned, another analog. There are bandspread and RIT to accommodate in addition. What do we do about T/R switching and timing if it's to be used in a transceiver? How about shielding specifications so it won't interfere with other cards? The only possible way I can see something like this being even possible is for a virtual "front panel" being done in software and appearing on a PC screen; only in that way could each card be sure that the necessary controls would be present. Some sort of serial bus with expandable protocol would be used for all controls. Then the question becomes, who will define, develop, and maintain the software? I can tell you from experience that it's no easy matter to keep any software working properly as new operating systems, protection software, and hardware appear. Add the necessary hardware interface to the equation and the job gets tougher yet. Oh, and what do you do when key components of the interface become obsolete and no longer available? It's common for people who've never had to design something which will be reproducible by the thousands and operate without error, to say how easy something will be. As one of those people who spent a career designing just such equipment, I'd bet serious money that the cost of development and maintenance of the interface would never pay itself back in sales. Unless, of course, it's done by volunteers. My question is: Why don't folks like "John Smith" get off their duffs and do it? Roy Lewallen, W7EL |
#3
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Roy:
Like Linux, a superior operating system when compared to windows--it would mainly be done by "the community"... all the hardware guys would have to do is make known the ports, address, etc... they are really un-needed from there--but, it would speed the takeoff of the "system" if they did provide a beginning point... and, one can always run a de-compressor (if they have compressed the executable), then a disassembler to asm, then a converter to "C" and, if you can program, you can now "tweak" the code anyway you would like... you will have a copy of it!!!! If the "hardware guys" didn't know how to provide a software interface, there are "linux hams" who would, most likely, if asked, "sponsor" such a effort on the Linux platform--hopefully--the interface to such a radio would bypass BOTH Mac and Windows, why these OS's are sufficient for home users, non-technical business and gov't--the technical mind deserves more, the power of linux (unix really) would serve them much better... However, the "system" we are speaking of would ONLY require a software interface if you inserted that card/module which allowed computer control, otherwise it would be using the analog card/module and associated faceplate... I think most here start right out trying to "limit" this "system" I have put forward--there would be no limits to it... if you can see a limit, that is only a bug which needs designed around... The homebrew community might be the best place to design, develop and introduce this from... as, if you allow too greedy a manufacturer control--it will just end up dying from his/her attempts to squeeze too much blood from the turnip!!! That is what has happened in the past... Warmest regards, John -- When Viagra fails to work--you are DOOMED!!! "Roy Lewallen" wrote in message ... |I don't think much of the discussion has looked very closely at what I | think is envisioned here -- a mainframe which would accept various | "cards" from numerous vendors. As I detailed in an earlier posting, it's | tough enough (and costly) to make a robust interface when a single | company has full control of the mainframe and plugins. But let's think a | little about the problems of making a mainframe which could accommodate | cards from various vendors -- cards which have different performance | characteristics. | | The first question is, who will define the interface? Who will dictate | modifications as they become necessary? | | Then let's consider a vendor who wants to make, say, an audio amplifier | card. It has digital signal processing with a dozen different modes. | Each mode has considerable adjustment range, for example the width of a | bandpass filter. The interface would have to have pins dedicated to | these functions, and the front panel would have to have switches and | controls for them. How about an oscillator? One might be digitally | tuned, another analog. There are bandspread and RIT to accommodate in | addition. What do we do about T/R switching and timing if it's to be | used in a transceiver? How about shielding specifications so it won't | interfere with other cards? | | The only possible way I can see something like this being even possible | is for a virtual "front panel" being done in software and appearing on a | PC screen; only in that way could each card be sure that the necessary | controls would be present. Some sort of serial bus with expandable | protocol would be used for all controls. | | Then the question becomes, who will define, develop, and maintain the | software? I can tell you from experience that it's no easy matter to | keep any software working properly as new operating systems, protection | software, and hardware appear. Add the necessary hardware interface to | the equation and the job gets tougher yet. Oh, and what do you do when | key components of the interface become obsolete and no longer available? | | It's common for people who've never had to design something which will | be reproducible by the thousands and operate without error, to say how | easy something will be. As one of those people who spent a career | designing just such equipment, I'd bet serious money that the cost of | development and maintenance of the interface would never pay itself back | in sales. Unless, of course, it's done by volunteers. My question is: | Why don't folks like "John Smith" get off their duffs and do it? | | Roy Lewallen, W7EL |
#4
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I'm eagerly awaiting the block diagram and system specification which I
assume you'll be working on. I'm sure it won't take you long. Good luck! Roy Lewallen, W7EL John Smith wrote: Roy: Like Linux, a superior operating system when compared to windows--it would mainly be done by "the community"... all the hardware guys would have to do is make known the ports, address, etc... they are really un-needed from there--but, it would speed the takeoff of the "system" if they did provide a beginning point... and, one can always run a de-compressor (if they have compressed the executable), then a disassembler to asm, then a converter to "C" and, if you can program, you can now "tweak" the code anyway you would like... you will have a copy of it!!!! If the "hardware guys" didn't know how to provide a software interface, there are "linux hams" who would, most likely, if asked, "sponsor" such a effort on the Linux platform--hopefully--the interface to such a radio would bypass BOTH Mac and Windows, why these OS's are sufficient for home users, non-technical business and gov't--the technical mind deserves more, the power of linux (unix really) would serve them much better... However, the "system" we are speaking of would ONLY require a software interface if you inserted that card/module which allowed computer control, otherwise it would be using the analog card/module and associated faceplate... I think most here start right out trying to "limit" this "system" I have put forward--there would be no limits to it... if you can see a limit, that is only a bug which needs designed around... The homebrew community might be the best place to design, develop and introduce this from... as, if you allow too greedy a manufacturer control--it will just end up dying from his/her attempts to squeeze too much blood from the turnip!!! That is what has happened in the past... Warmest regards, John |
#5
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Hmmm, you know, basically just two guys built the first apple desktop
computer--you think it is that much more difficult? Well, maybe! I think one can begin with at least a mental pic... ....all the voltages which are to be used run on a common bus, the digital lines are there to, without the "motherboard card", these are pretty much unused... the audio lines can be hear for digital cards (on the bus for the audio amp card)--very low level rf might have access though a proper connector, of some sort (maybe on a shelf now, maybe need to do new specs for one), there is a bnc/so-239, etc... which "floats" in a slot, capable of sliding along to gain access to all cards (why limit where the PA will be inserted?)...an analog bus with connectors available to each card lays on a line which is also available to any cards requiring it, and provides connection to a plug which is accessible if an analog panel is used--on this analog panel are standard components (which may be all there, or added one at a time, as needed)--meter, vol, squelch, rf gain, tuning (variactor card, or old variables if room) lcd readout, etc... Certainly one would just begin with the case, power supply, and the bus(s) providing everything one can imagine a "card designer/builder" would require in the future--and put some flexibility in it, just in case you want to do a case revision/upgrade in the future, maybe you start out with too big a case right now--looking forward to future times when it would be desirable to have it smaller, etc...... rf out, rf in?, audio, etc lines--duplicate most everything in both digital and analog-- ... then "analog panel"/"digital panel" connectors... maybe expect the case to house no larger than a 100-500 watt PA... larger power through an external unit... You point is well taken that my bench, time and abilities are limited--I am trying to finish putting three boys through college... .... even my overpaid colleges at work just wanna sip beer on the weekends and watch the game or dvds, or plan the next cruise--could be a sign of my generations age or decline... my access to real "innovators" is limited... so is this countries... .... but, as has been pointed out--this newsgroup is read in other countries... countries where innovation is not dying but, rather just blooming... And, placed beside the first apple desktop (built by, basically, two boys in a college lab and a garage)--I think most would say "IT IS DO-ABLE!" Warmest regards, John -- When Viagra fails to work--you are DOOMED!!! "Roy Lewallen" wrote in message ... | I'm eagerly awaiting the block diagram and system specification which I | assume you'll be working on. I'm sure it won't take you long. Good luck! | | Roy Lewallen, W7EL | | John Smith wrote: | Roy: | | | | Like Linux, a superior operating system when compared to windows--it would | mainly be done by "the community"... all the hardware guys would have to do | is make known the ports, address, etc... they are really un-needed from | there--but, it would speed the takeoff of the "system" if they did provide a | beginning point... and, one can always run a de-compressor (if they have | compressed the executable), then a disassembler to asm, then a converter to | "C" and, if you can program, you can now "tweak" the code anyway you would | like... you will have a copy of it!!!! | | | | If the "hardware guys" didn't know how to provide a software interface, | there are "linux hams" who would, most likely, if asked, "sponsor" such a | effort on the Linux platform--hopefully--the interface to such a radio would | bypass BOTH Mac and Windows, why these OS's are sufficient for home users, | non-technical business and gov't--the technical mind deserves more, the | power of linux (unix really) would serve them much better... | | | | However, the "system" we are speaking of would ONLY require a software | interface if you inserted that card/module which allowed computer control, | otherwise it would be using the analog card/module and associated | faceplate... | | | | I think most here start right out trying to "limit" this "system" I have put | forward--there would be no limits to it... if you can see a limit, that is | only a bug which needs designed around... | | | | The homebrew community might be the best place to design, develop and | introduce this from... as, if you allow too greedy a manufacturer | control--it will just end up dying from his/her attempts to squeeze too much | blood from the turnip!!! That is what has happened in the past... | | | | Warmest regards, | John |
#6
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.... I forgot to mention, that while the minimal OS of the radio itself would
be a minimal linux kernal--a USB, TCP, serial, parallel, etc hardware interface could be chosen so windows users would find it transparent--and they access the radio either through a GUI or commandline interface... when using the digital capabilities... The most basic starter of this radio might be a regen receiver (or TRF) and a one watt xmitter board and analog of course... great for new "bootstrapping" hams... Warmest regards, John -- When Viagra fails to work--you are DOOMED!!! "John Smith" wrote in message ... | Roy: | | | | Like Linux, a superior operating system when compared to windows--it would | mainly be done by "the community"... all the hardware guys would have to do | is make known the ports, address, etc... they are really un-needed from | there--but, it would speed the takeoff of the "system" if they did provide a | beginning point... and, one can always run a de-compressor (if they have | compressed the executable), then a disassembler to asm, then a converter to | "C" and, if you can program, you can now "tweak" the code anyway you would | like... you will have a copy of it!!!! | | | | If the "hardware guys" didn't know how to provide a software interface, | there are "linux hams" who would, most likely, if asked, "sponsor" such a | effort on the Linux platform--hopefully--the interface to such a radio would | bypass BOTH Mac and Windows, why these OS's are sufficient for home users, | non-technical business and gov't--the technical mind deserves more, the | power of linux (unix really) would serve them much better... | | | | However, the "system" we are speaking of would ONLY require a software | interface if you inserted that card/module which allowed computer control, | otherwise it would be using the analog card/module and associated | faceplate... | | | | I think most here start right out trying to "limit" this "system" I have put | forward--there would be no limits to it... if you can see a limit, that is | only a bug which needs designed around... | | | | The homebrew community might be the best place to design, develop and | introduce this from... as, if you allow too greedy a manufacturer | control--it will just end up dying from his/her attempts to squeeze too much | blood from the turnip!!! That is what has happened in the past... | | | | Warmest regards, | John | -- | When Viagra fails to work--you are DOOMED!!! | | "Roy Lewallen" wrote in message | ... ||I don't think much of the discussion has looked very closely at what I || think is envisioned here -- a mainframe which would accept various || "cards" from numerous vendors. As I detailed in an earlier posting, it's || tough enough (and costly) to make a robust interface when a single || company has full control of the mainframe and plugins. But let's think a || little about the problems of making a mainframe which could accommodate || cards from various vendors -- cards which have different performance || characteristics. || || The first question is, who will define the interface? Who will dictate || modifications as they become necessary? || || Then let's consider a vendor who wants to make, say, an audio amplifier || card. It has digital signal processing with a dozen different modes. || Each mode has considerable adjustment range, for example the width of a || bandpass filter. The interface would have to have pins dedicated to || these functions, and the front panel would have to have switches and || controls for them. How about an oscillator? One might be digitally || tuned, another analog. There are bandspread and RIT to accommodate in || addition. What do we do about T/R switching and timing if it's to be || used in a transceiver? How about shielding specifications so it won't || interfere with other cards? || || The only possible way I can see something like this being even possible || is for a virtual "front panel" being done in software and appearing on a || PC screen; only in that way could each card be sure that the necessary || controls would be present. Some sort of serial bus with expandable || protocol would be used for all controls. || || Then the question becomes, who will define, develop, and maintain the || software? I can tell you from experience that it's no easy matter to || keep any software working properly as new operating systems, protection || software, and hardware appear. Add the necessary hardware interface to || the equation and the job gets tougher yet. Oh, and what do you do when || key components of the interface become obsolete and no longer available? || || It's common for people who've never had to design something which will || be reproducible by the thousands and operate without error, to say how || easy something will be. As one of those people who spent a career || designing just such equipment, I'd bet serious money that the cost of || development and maintenance of the interface would never pay itself back || in sales. Unless, of course, it's done by volunteers. My question is: || Why don't folks like "John Smith" get off their duffs and do it? || || Roy Lewallen, W7EL | | |
#7
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Well, most of this requires VERY little innovation and only DUPLICATION...
Many manufacturers make motherboards, hd's, cd's, video cards, audio cards, tv cards, radio cards, network cards, port expansion cards, home security cards, security cams, credit card readers, security readers (finger print, eye retina, etc) etc, etc... .... That many manufactures share one case with great ease--is made obvious by the computer on your desktop--indeed--on excellent motherboards, they are NOT picky about even the processor!!! Intel, Cyrix, AMD, IBM, VIA, etc (even providing sockets with different pin configurations for different processors!)... (Some no longer available--they come and they go) Don't go name brand junk: HP, Dell, Toshiba, Sony, etc--but go generic IBM case and the world of computer manufacturers is available to you... and look at the laptop--you know why EVERYONE in the world doesn't have one? BECAUSE THERE IS NO GENERIC CASE!!!! You are stuck with proprietary junk!!! Both in rec.radio.amateur.antenna and here there are far more focused on why something can't be done, than why it can--I think if one ignores this--it can be done!... this is interesting... and is why I began a thread on progress.... especially since so many thought there was no reason to even mention it... One more thing, just make a generic case for a laptop platform, make the platform available to support other manufacturers components--guess what... Warmest regards, John -- When Viagra fails to work--you are DOOMED!!! "Roy Lewallen" wrote in message ... |I don't think much of the discussion has looked very closely at what I | think is envisioned here -- a mainframe which would accept various | "cards" from numerous vendors. As I detailed in an earlier posting, it's | tough enough (and costly) to make a robust interface when a single | company has full control of the mainframe and plugins. But let's think a | little about the problems of making a mainframe which could accommodate | cards from various vendors -- cards which have different performance | characteristics. | | The first question is, who will define the interface? Who will dictate | modifications as they become necessary? | | Then let's consider a vendor who wants to make, say, an audio amplifier | card. It has digital signal processing with a dozen different modes. | Each mode has considerable adjustment range, for example the width of a | bandpass filter. The interface would have to have pins dedicated to | these functions, and the front panel would have to have switches and | controls for them. How about an oscillator? One might be digitally | tuned, another analog. There are bandspread and RIT to accommodate in | addition. What do we do about T/R switching and timing if it's to be | used in a transceiver? How about shielding specifications so it won't | interfere with other cards? | | The only possible way I can see something like this being even possible | is for a virtual "front panel" being done in software and appearing on a | PC screen; only in that way could each card be sure that the necessary | controls would be present. Some sort of serial bus with expandable | protocol would be used for all controls. | | Then the question becomes, who will define, develop, and maintain the | software? I can tell you from experience that it's no easy matter to | keep any software working properly as new operating systems, protection | software, and hardware appear. Add the necessary hardware interface to | the equation and the job gets tougher yet. Oh, and what do you do when | key components of the interface become obsolete and no longer available? | | It's common for people who've never had to design something which will | be reproducible by the thousands and operate without error, to say how | easy something will be. As one of those people who spent a career | designing just such equipment, I'd bet serious money that the cost of | development and maintenance of the interface would never pay itself back | in sales. Unless, of course, it's done by volunteers. My question is: | Why don't folks like "John Smith" get off their duffs and do it? | | Roy Lewallen, W7EL |
#8
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On Mon, 09 May 2005 16:17:59 -0700, Roy Lewallen
wrote: Then the question becomes, who will define, develop, and maintain the software? I can tell you from experience that it's no easy matter to keep any software working properly as new operating systems, protection software, and hardware appear. Add the necessary hardware interface to the equation and the job gets tougher yet. Oh, and what do you do when key components of the interface become obsolete and no longer available? There are large, well established operating system created and maintained by volunteers. The problem with some special hardware is often that the hardware interface specification is not publicly available (as with some 3D graphics cards). Writing a device driver for some radio modules would not be that hard, provided that the module control is designed in a somewhat sensible way. As long as the hardware interface specs are available for these modules, the software is not going to be the show stopper. Paul OH3LWR |
#9
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This reminds me of the Dilbert cartoon on my wall:
PHB (Pointy-Haired Boss), pointing to flip chart graph of declining sales: "Our sales are dropping like a rock." PHB, pointing to flip chart graph labeled "Future" and steadily rising: "Our plan is to invent some sort of doohickey that everyone wants to buy." PHB, to Dilbert: "The visionary leadership part is done. How long will your part take?" Roy Lewallen, W7EL |
#10
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Roy Lewallen wrote:
This reminds me of the Dilbert cartoon on my wall: PHB (Pointy-Haired Boss), pointing to flip chart graph of declining sales: "Our sales are dropping like a rock." PHB, pointing to flip chart graph labeled "Future" and steadily rising: "Our plan is to invent some sort of doohickey that everyone wants to buy." PHB, to Dilbert: "The visionary leadership part is done. How long will your part take?" Roy Lewallen, W7EL Wonderful! I missed that one somewhere. 73, CJ KØCJ |
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