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#21
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And now for something totally different!
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#22
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And now for something totally different!
On Mar 6, 12:56Â am, Dave Heil wrote:
wrote: On Mar 5, 3:09�pm, Dave Heil wrote: wrote: On Mar 3, 8:23pm, Dave Heil wrote: A few years ago, a small company began manufacturing a reduction knob for the 75A-4, machined out of solid brass. Functional and attractive. I noted them when I saw the ads in Electric Radio.  The price was very dear. $125 IIRC. How did it provide PBT? I'm going to have to dig out the paperwork on the Universal Service unit (which I got copies of just a year or two back) and let you know. Will be good to know. The CW filter I have is the 800 Hz unit.  One of these days I may replace it with an Inrad unit.  I'll have to juggle things a bit to match the modern Collins mechanical filter to the radio. I think the same company that made the reduction knob made exact plug- in filters. Dunno if they made a CW one. At the University ham shack we had two 75S-3s. One had the 200 Hz filter, aka "the ringmaster". But boy could they hear! IIRC the 1-A predated the S-line and KWM-2. I think you'll find that all of them hit the market in '57. The KWM-2 came after the original S-line (75S-1/32S-1) Check your old QSTs, you'll see the 1-A advertised well before the KWM-2. It was a revolutionary design; small, light and compact at a time when even inexpensive receivers were big and heavy. Note the tiny, taller-than-it-is-wide front panel and the very deep chassis. Unfortunately it was built as an SSB-only receiver.  There were no provisions for a narrow filter for CW or a wider one for AM.  In fact, the BFO could not be turned off at all.  I sold a number of rig s after coming back stateside and the Drake 1-A was one of them. 1-A was Drake's entry into the ham receiver market; previously they had only made things like lowpass filters. Their idea was to cut the cost of SSB to the bone by making a receiver specific to the mode and leaving out anything not needed for SSB. Hence no diode detector, no BFO-off, no narrow filter, etc. But it had PBT, which also gave sideband selection, an S-meter and AGC that worked on SSB, and was very stable. That mode-specific thing inspired many of the Southgate receivers. The 2-A and 2-B are excellent receivers for their price and complexity, and are prized today. But they were a dead end in one way: there was no matching transmitter that could transceive with them. In the time when they were introduced, many folks were still using separates.  I've kept my 2-B because it really is a classic and performs well today.  The matching 2-BQ adds a lot to the receiver. About 15 years ago I walked away from a hamfest table that had a 2-B/2-BQ combo for $75. "To think about it". Oh fer dumb..... What the KWM-2 and S-line did was to make "transceiving" popular. Well, they made it popular for those with lots of money. Not just those folks. The idea got wide publicity and led to lots more rigs at a lot lower prices. If I recall correctly, there were identical-looking models with two different power output levels. Cosmophone 35 and Cosmophone 1000. Indeed, a homebrew 40 meter *CW* transceiver built around a surplus BC-453 was described in a 1954 QST, probably the first published use of the idea in amateur radio. It even had full QSK. But it was ahead of its time. You've aroused my curiosity.  I'll have to dig through the back issues and check it out.  There's a '453 lying about here somewhere. IIRC the author's last name was Deane. I do not know of any earlier HF amateur transceiver being described in QST or any other publication. The KWM-2 and S-line took transceiving to another level. Not only were they smaller and lighter than their predecessors, they had relatively few controls. They made SSB more popular with hams by reducing the cost and size and eliminating the job of zerobeating the transmitter. Tune an SSB station correctly and the transmitter was automatically on the right frequency. I have to disagree with the reduction of cost.  When the KWM-2 was introduced, my dad made a little less than $6,000 per year gross pay as a Miami Herald reporter.  That transceiver would have cost about a quarter of a year's pay. And $6000/yr gross income was solid middle class. A family of four could live very well on $6K, 50 years ago. What I meant was that a KWM-2 and power supply/speaker cost less than top-of-the-line separates like a 75A-4 and HT-32B. Or compare the price of an S-line and a KWM-2. To get an idea of the influence of the KWM-2, google "LWM-3"...  Fast forward a bit.  When I bought a Ten-Tec Omni VI, the new cost was a small fraction of a year's pay and that rig offered features only dreamed about at the time of the introduction of the Collins rig.  The KWM-2 was smaller and lighter but an HT- 32B and an HQ-170 would have been cheaper by hundreds of dollars. Agreed. But the KWM-2 put the idea of the one-box station out there in a big way. A lot of less-expensive transceivers with minimal controls followed. People saw the success of the KWM-2 and designed less-expensive alternatives based on the idea. Add to this the grounded-grid linear amplifier and things really changed. High power 'phone became not only less expensive but a lot smaller and lighter. Transceivers and matched-pair separates became the new paradigm in HF ham gear; AM wasn't part of that. There are a couple of "duh" factors buried in there for us to mull over. It would have been possible for radio amateurs to have built and used grounded-grid linear amps for use with AM rigs much earlier.  A rig such as the Johnson Ranger would have driven one to a KW AM input with ease. Some hams did that but the big problem was the low efficiency of AM linear without the use of special circuits like the Doherty, which isn't the fastest QSY circuit. With AM linear you only get 30-35% carrier efficiency. Which means 300-350 watts carrier at the old 1 kW legal limit. Plus your final tubes have to be able to dissipate 650-700 watts! The same results could be had from a 450-watt class plate-modulated AM rig - say, a pair of 812As modulated by a pair of 811As. AM also required power supplies that could stand the 100% duty cycle of the mode. The low duty cycle of early unprocessed SSB rigs meant a lot of liberty could be taken in PSU design. The end result was rigs like the NCX-3 and the SB-100, which cost as much as a good receiver but were complete 100-watt SSB stations that you could indeed set up on a card table. When Heath introduced the SB-200 in 1954, it cost $200. Legal limit on CW, 1200 watts PEP on SSB (input). That was a lot cheaper than the equivalent AM, and would fit on the card table. IOW, high power AM cost a lot of dough and a lot of space/weight. The SSB transceiver/GG linear paradigm drastically reduced those requirements. Fun fact: AFAIK only two 1 kW-input-legal-limit plate-modulated AM rigs were ever made for the amateur market: the Collins KW-1 and the Johnson Desk Kilowatt. Total production was very limited - maybe 2000 units combined. I can't begin to recall the number of models of legal-limit GG amplifiers made. EFJ Thunderbolt, SB-220, Heath KL-1... More to come... 73 de Jim, N2EY |
#23
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And now for something totally different!
Dave Heil wrote:
I'm going to use an old computer tower for a chassis/cabinet for a pair of 4-400's I plan to build. I shouldn't post late at night when I'm tired. What I meant to say was that I plan to use the old computer tower for the power supply, not the entire amp. Dave K8MN |
#24
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And now for something totally different!
On Mar 5, 3:20Â pm, Dave Heil wrote:
wrote: On Mar 3, 2:40�pm, Michael Coslo wrote: Agreed - but in the Triple-F aesthetic (hereafter referred to as  "The Southgate School" or TSS), not defeating function isn't enoug h. All choices must enhance or support functionality. Gotcha, Jug! Marcellus? Is that you? IOW, "found objects". If you're willing to get dirty and are patient, it is possible to save a bundle by using other people's castoffs. Not only that, but make a dent in the enormous waste stream. I'm going to use an old computer tower for a chassis/cabinet for [the power supply of] a pair of 4-400's I plan to build. You want a Southgate type number for it? If you're building something small, try hobby shops.  They often have bins of both brass, copper and aluminum sheet in various thicknesses along with round and square tubing and rod of the same materials. Yes, but they want you to *buy* the stuff! My adapters were made from scraps. Wood with a thin sheet of flashing aluminum is one way to get the shieldin g. BTDT, except used old litho plates turned print-side-in. TSS is about simplicity and functionality, not minimalism. If staining or finishing improves the functionality, it is done. For example, the shack tabletop consists of a layer of oriented strandboard (for strength) topped by a layer of masonite (for a smooth hard surface). This combination (actually a composite) was chosen because it was the least expensive at the time. The masonite was given a couple of coats of varnish because doing so improved the functionality. The tempered Masonite, no doubt.  The front panel of W4JBP's 1941 homebrew transmitter is of that stuff, painted black. Exactly. Wood prices have changed, though; today a tabletop might be AC plywood. Depends what's on the cull cart. Possibly. I've had some experience building speaker cabinets (clones of the Altec A-7 "Voice of the Theater", JBL folded horns, for example) and the trick is to build solid from the beginning. I've shared the experience and still remember all of the kerfing that went into getting those curves right.  Add a 15" Electrovoice SRO speaker (which was about 3db better than anything else on the market at the time), top is with some massive horn tweeters and you had something. The ones I helped build in the 1960s are still in service. I've always wondered what the fascination with "antiques" is. I can understand the fascination with craftsmanship, design, practicality and materials, though. I think there a couple of classes of antique furniture items.  There are those things which can only be viewed and those things which can be used.  A small, antique ladies chair might not be something you could use, but an antique dining room suite or an antique sideboard can be quite utilitarian. The former belongs in a museum, the latter in a home. The term I would use is "classic" or "timeless". Look at some Mission or Shaker furniture - it does not appear "antique" or dated. That's what TSS is all about, applied to Amateur Radio (and a limited budget!) I had to grin.  I believe that 2x4's, 4x4's, plywood or hollow core doors will never go out of style. I rip 2x4s in half lengthwise; they're all you need for most shack furniture. Also do an offset cut that gives one piece 1-1/2" square and another that's 2x1-1/2" from a single 2x4. Table saw makes it easy. I did one table with a hollow core door many years ago (it was free) but they are too flimsy and too expensive for TSS approval now. The shack table in the website picture was designed for Field Day use, 25 years ago. The top was the maximum size that would fit in the back of a VW Rabbit with the rear seat taken out. All the legs and braces are bolted on in such a way that the whole thing breaks down into one package. Does the job for now but a replacement is in the works. Maybe.  There's no "Captain Nemo walking into his cabin on the Nautilus" look here, but the place is attractive and utilitarian. IMHO the true art of a hamshack is having things set up in such a way that you just want to sit down and start operating as soon as you see the place. 73 de Jim, N2EY |
#25
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And now for something totally different!
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#26
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And now for something totally different!
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#27
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And now for something totally different!
Dave Heil wrote in
: Michael Coslo wrote: Dave Heil wrote: some snippage Sorry for the late reply on this, esp since the thread has taken a different direction, but I though it deserved a reply.... Maybe. Another wire, mounted diagonally from the rear would have done away with most of the pendulum action. If you're worried about buildings shaking, even a steel mounted would have such vibrations transfered to the projector. The wires might have even damped those types of motion. Using wires does not work. The reason is that buildings do not shake in the way most people think. The building may shake in one axis, and not another, and may shake in multiple directions, but not the same amount in all axes, or at the same time. This will have the effect of pulling the entire assembly in one direction or another, depending on "whats a-shakin'", and which wire is pulling more at the moment. However, on a good sturdy ceiling mount, that has a resonance frequency as high as practical, building movement is not much of a problem, unless the building is on the verge of shaking itself apart. The reason is that rapid pendulum damping with little movement gets rid of pendulum moment, and that most floors tend to shake closely with the ceiling on any given level, so the people are moving along with the image and screen. I've never seen a professional design with wires, although I've seen a few designed by others, and they all have damping problems, all related to the multifilar pendulums they create. Oddly, the wire systems I've seen were "designed" and built by engineers who thought they could remove all the filar pendulum movement by going multifilar. That inherently creates more complexity in movement. The answer is in that the projector on the end of that pendulum becomes very similar to a mirror galvanometer, greatly amplifying the movement by the time the light hits the wall. Absolutely! This aesthetic is in no way saying "look at me! I'm serious art!" I would go a little further to state that some examples of the genre are downright ridiculous - by design. ...and I'd go even further in saying that most of it is downright ridiculous by design or otherwise. There is room in this world for a lot of different tastes. Some I like, some I do not. I am always careful to not call any of them ridiculous so that I don't indadvertantly insult someone. 8^) Kitsch is kitsch no matter who tosses the pillows with a flair. That being said, there are examples of great beauty in there, on the workshop page, the telegraph sounder was gorgeous, and the pick guard on the Stratocaster is beautiful. I own a perfectly good '73 Strat. I'm defacing it for no one. I have a hard time agreeing that *that* Strat was defaced. I have a white on white Strat myself, and am happy to keep it that way, but there are a lot of places who do custom guitar work or design: http://www.sparrowguitars.com/ http://www.terrapinguitars.com/ http://www.warmoth.com/ Even Fender: http://www.fender.com/customshop/home/index.php There is actually some of this aesthetic running about in Amateur radio, even if we don't notice it. It isn't evident here. I disagree, respectfully, more below. snippage Some kind of plating or paint is needed and it isn't practical to paint things like the threads of screws. Key's aren't designed to look as if they're steam powered. Precious metal plating is not there because it is practical, all those keys are quite embellished, and can we tell the difference between a gold plated and a painted one in operation? They also have unneeded shapes, and Mister Begali calls them art. I find them to be quite beautiful, and a magnificent tour de force in mechanical design in the prosaic function of a telegraph key, but would not try to argue that they are somehow based on practicality. That's pretty much my input on the subject until I have the operating are designed and built. My shack may not be to everyone's tastes, but hopefully I'll like it! 8^) - 73 de Mike N3LI - |
#28
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And now for something totally different!
Mike Coslo wrote:
Dave Heil wrote in : Michael Coslo wrote: Dave Heil wrote: some snippage Sorry for the late reply on this, esp since the thread has taken a different direction, but I though it deserved a reply.... Maybe. Another wire, mounted diagonally from the rear would have done away with most of the pendulum action. If you're worried about buildings shaking, even a steel mounted would have such vibrations transfered to the projector. The wires might have even damped those types of motion. Using wires does not work. The reason is that buildings do not shake in the way most people think. The building may shake in one axis, and not another, and may shake in multiple directions, but not the same amount in all axes, or at the same time. Okay, so what you earlier described as the motor fan causing a pendulum motion wasn't exactly correct then. What you've described could be described as random orbital in nature or, at times, even multiple pendula. This will have the effect of pulling the entire assembly in one direction or another, depending on "whats a-shakin'", and which wire is pulling more at the moment. I'm thinking that if you've got a building doing *that much shaking*, you've got more problems than a projector moving a bit. However, on a good sturdy ceiling mount, that has a resonance frequency as high as practical, building movement is not much of a problem, unless the building is on the verge of shaking itself apart. The reason is that rapid pendulum damping with little movement gets rid of pendulum moment, and that most floors tend to shake closely with the ceiling on any given level, so the people are moving along with the image and screen. I'm getting dizzy already, Mike. I've never seen a professional design with wires, although I've seen a few designed by others, and they all have damping problems, all related to the multifilar pendulums they create. Oddly, the wire systems I've seen were "designed" and built by engineers who thought they could remove all the filar pendulum movement by going multifilar. That inherently creates more complexity in movement. The answer is in that the projector on the end of that pendulum becomes very similar to a mirror galvanometer, greatly amplifying the movement by the time the light hits the wall. This is getting really close to becoming a Cecil moment. :-) Absolutely! This aesthetic is in no way saying "look at me! I'm serious art!" I would go a little further to state that some examples of the genre are downright ridiculous - by design. ...and I'd go even further in saying that most of it is downright ridiculous by design or otherwise. There is room in this world for a lot of different tastes. Some I like, some I do not. I am always careful to not call any of them ridiculous so that I don't indadvertantly insult someone. 8^) You must never be so sensitive about what people might think of your opinion that you become afraid to express it. If you think that a certain style is kitschy or silly, you're permitted to say so. So am I. Kitsch is kitsch no matter who tosses the pillows with a flair. That being said, there are examples of great beauty in there, on the workshop page, the telegraph sounder was gorgeous, and the pick guard on the Stratocaster is beautiful. I own a perfectly good '73 Strat. I'm defacing it for no one. I have a hard time agreeing that *that* Strat was defaced. I have a white on white Strat myself, and am happy to keep it that way, but there are a lot of places who do custom guitar work or design: http://www.sparrowguitars.com/ http://www.terrapinguitars.com/ http://www.warmoth.com/ Even Fender: http://www.fender.com/customshop/home/index.php Sure. Places which will do nearly anything for a buck abound. Some of the work is skillfully done, but still ends up looking tacky. There is actually some of this aesthetic running about in Amateur radio, even if we don't notice it. It isn't evident here. I disagree, respectfully, more below. snippage Some kind of plating or paint is needed and it isn't practical to paint things like the threads of screws. Key's aren't designed to look as if they're steam powered. Precious metal plating is not there because it is practical, all those keys are quite embellished, and can we tell the difference between a gold plated and a painted one in operation? No, we can't. That doesn't stop the gold plated one from looking better to most of us. Gold doesn't oxidize the same as most other metals. It doesn't need to be polished often. Gold in contacts is used where low conact resistance is desired. In the old days, keys usually had appreciable current running through them. With low current, solid state circuits, a little oxidation on contacts can result in a keying circuit malfunctioning. No keys which are currently produced are made to look as if they're steam powered. They also have unneeded shapes, and Mister Begali calls them art. Some folks think an abstract painting done by a Chimpanzee is art. I don't agree with them. Begali keys are well made. They're attractive to some. I find them to be quite beautiful, and a magnificent tour de force in mechanical design in the prosaic function of a telegraph key, but would not try to argue that they are somehow based on practicality. Keys got prosaic function? The Begalis, like all other keyer paddles are designed to do a certain job. They can be as attractive as one can make them, but if they cannot do the job reasonably well, they fail. That's pretty much my input on the subject until I have the operating are designed and built. My shack may not be to everyone's tastes, but hopefully I'll like it! 8^) You're the only guy who needs approve. Dave K8MN |
#29
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And now for something totally different!
On Mar 9, 5:00Â pm, Dave Heil wrote:
wrote: On Mar 6, 12:56� am, Dave Heil wrote: wrote: On Mar 5, 3:09�pm, Dave Heil wrote: Remember too that in the 1970s US ham radio was growing fast. This was right after the 1968-1969 "incentive licensing" changes which some said were going to destroy amateur radio. The numbers tell a different story. They surely do.  About the time I first became licensed, I think ther e were about 300k radio amateurs in the U.S. and only about 100k in the entire rest of the world. I'm not sure of the exact year you were licensed but if it was in the 1960s the number of US hams was about 250K not 300K. As for the rest of the world, 100K back then was pretty accurate *except* for Japan's 4th class licenses. In that time period, a number of the classic US ham radio manufacturers were losing their founders, either through sale of the company or retirements, etc. Right.  The Drake firm stayed in the family and Swan stayed with the original owner until he sold it to Cubic, circa 1980. And we see what happened... All Southgate Radio receivers from the Type 3 onward have had slow tuning rates - typically 5 to 7 kHz per turn. That's about 1969 to the present. ...and that's a good tuning rate. I used to wonder why most older equipment tuned so fast. One reason was cost; a simple string or pinch drive cost a lot less than gears. But even expensive stuff like the HROs had fast tuning by Southgate standards. I think the way hams operated in the past was a big reason. Split operation was pretty standard even before crystal control was common in ham rigs, so if you called CQ, an answer might be anywhere in the band. Around 1964, National introduced the solid state, synthesized HRO-500.  They were expensive problem children.  There have been numerous problems with the PLL circuitry.  I bought one in 1997 and i t had (Surprise!) PLL problems. I sold it. Even with a working PLL, the '500 had bad intermod and dynamic range problems for such an expensive rx. About the only company besides Collins that was able to come into the ham radio market at the top was Signal One - which didn't last. Kachina tried it and that didn't last very long. Kachina had an entirely new concept: the computer-controlled rig without a front panel. That still hasn't really caught on. Well, that leaves us discussing what was built vs. what might have been built. Point is, the Japanese rigs put those features in from the get-go, while the American rigmakers didn't. Right.  It was a new game.  The JA manufacturers recognized that bells and whistles would lure buyers. Not just bells and whistles but basic things like RIT, sharp filters, decent dial drives and the ability to turn off the AGC. Built in or as options, not as mods. Varactor in the PTO? Yep, with a relay switching scheme. The Southgate Type 6 and Type 7 achieve RIT without a varactor diode. In fact, there are no solid state devices at all in either rig except for two 1N34As in the SWR bridge of the Transmatch. Guys argued with Drake for ages about the inclusion of CW filters and RIT in the transceivers. � The Drake folks couldn't understand how any one would need such things. � Interesting! I always thought the reason they were left out was so that folks would buy the separates. Not exactly.  Drake figure that anyone who wanted to use CW *would* b uy the separates.  They just didn't figure that there was a market for transceivers among regular users of CW.  The light finally dawned. Of course that the meager CW features of the TR-4CW gave way to the advanced features of the TR-5 and TR-7. Which cost a bit more.... Sherwood has tested the Elecraft K3. Next issue of QST will carry a Product Review of it too. Yep.  The numbers look very, very good.  These days though, the difference between very good and very, very good is just a smidgen. Point is, you can get a very very good rig, American made, with direct connection to the makers of the rig, for less than a lot of mid-range rigs from Japan. 'Course not. But they weren't the target market, either. The SB-101/ HW-101 crowd were. Uh-huh.  It marked the end game for Heath.  The company just did n't realize it right away. Part of what changed too was the economy of kitbuilding. In the days of point-to-point wiring, a lot of the cost of manufactured electronics was the assembly labor. Kits eliminated that, but added the cost of the assembly manual and the inevitable problems of supporting the kitbuilders. Automated and semiautomated PCB-based manufacturing drastically reduced the assembly-labor cost. Another factor was alignment cost. Heath had to design their rigs so they could be aligned with minimal test gear. That's one reason for the preassembled LMO in the SB line and the preadjusted, sealed BPFs in them. That limit on design flexibility doesn't exist for a manufacturer who can spread the cost of test equipment over many units. I remember that towards the end of its run the HW-101 price reached $449, which was almost double its introductory price less than a decade earlier. That was without power supply, speaker, mike or sharp filter. And you had to build it. FT-101/TS-520S took that market! Right.  Don't forget that the JA rigs not only had an inboard, multi-voltage AC power supply; they included a DC supply for mobile use as well. Sort of. The TS-520S required the optional bolt-on DC-5 DC supply adapter for DC operation of the transmitter section. It consisted mostly of power transistors and a heat sink. It would not operate the '520 at full power; you were limited to about half power. In the TS-520SE, the last version, the DC option was eliminated and the rig became AC-mains only.  Neither of the two rigs mentioned actually came with a CW filter.  Those were optional accessories. Yup - but not an expensive one. I just look in the Southgate inventory. I can do that with many items.  There are some modern things which I just have to buy. The first way will be the renovators, who make a few good rigs from a pile of problem sets. This is already starting to happen; look on ebay for "TS-940" and you will see lots of parts for sale. Okay. � Gone are the days when you reach into bins of transisto r or IC 's and expect to be able to repair much of anything. � Large scale integrations and specialty chips took care of most of that. Kenwood rigs in particular seem to suffer. � The 930's, 850's a nd 940' s are examples of rigs where the displays and display drivers aren't available any longer. Agreed but there will be some rigs that have other problems but good displays. Oh yes, but those fluorescent displays, unlike the typical LED displays, go bad with time and use. I have enough #47 pilot lights for the foreseeable future... I knew a guy who once had machinists make him a part for a Cadillac power seat instead of paying what he considered to be an outrageous price for the part from GM.  I think he spent about four times what G M wanted. bwaahaahaa And consider: $125 for a reduction tuning knob for a receiver that went out of production more than 45 years ago? But those receivers are apt to be around for another few decades and are highly prized.  As I recall, there's still an outfit making highly stable digital remote VFOs for the Collins KWM-2 series. You can get almost anything you need for an S-line or the R-390/A. Including high-quality videos on how to do the work. There are folks still building HBRs today, from scratch. I'd think that getting some of the parts could be really difficult. You'd be surprised what folks have squirreled away.... Nooooooo, I don't think I would.  W9ZR asked in the boatanchors newsgroup if anyone had the bowl insulator from an ART-13.  I sent hi m one. I bet it wasn't the only one you had. In reality the only unobtanium parts are the coil forms and IF cans. One trick is to use ARC-5 IFTs instead. But I prefer original Southgate designs. Those IF transformers are one of the things I was thinking about.  I have loads of large and miniature 455KC stuff, but nothing like the higher frequency cans. A BC-454 (tuning range 3-6 Mc.) has a 1415 kc. IF. I'm looking at the Tokyo Hi Power 1.5 KW job, but it is expensive.  I f the Starkville, Mississippi gang gets their act together, we may see an affordable high power, solid state amp in the near future. The K3 has put the Elecraft amps on the back burner for a while. I suspect that will change once the slack runs in. 73 de Jim, N2EY |
#30
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And now for something totally different!
On Mar 9, 4:10Â pm, Dave Heil wrote:
wrote: On Mar 5, 3:20� pm, Dave Heil wrote: wrote: On Mar 3, 2:40�pm, Michael Coslo wrote: Gotcha, Jug! Marcellus? Is that you? Complete with insignia! Almost time to put the blue sweaters away. There's no one who can reduce a waste stream like West Africans.  The seams in Coke cans are opened after the tops and bottoms are removed and the cans are rolled flat.  The become roofing material or house siding. Black trash bags are washed and recycled.  Pop bottles become water bottles and used 55-gallon drums (previous contents unknown) are used for making palm or cashew wine. Except for the reuse of possibly-contaminated 55-gal drums it all sounds good. The dial drum of the Southgate Type 7 was made from a piece of 6" diameter plexiglass pipe. It was thoroughly cleaned and about a 2" long section cut off. A disk 6" in diameter was then cut and the pipe solvent-welded to the disk using Duco. The neutralizing-adjustment disk from a BC-375 tuning unit was then bolted to the bottom so that the dial drum could be mounted on an extension of the tuning capacitor shaft. The dial drum is viewed through a Plexiglas window. A piece of paper wrapped around the drum was calibrated using an LM frequency meter, then a good copy drawn using a CAD program. The good copy was printed on translucent Mylar and put on the drum. A lampholder/reflector assembly is mounted inside the dial drum, with two pilot lights so the whole thing is illuminated. You want a Southgate type number for it? I think that'd be appropriate. Indeed! I will speak with Engineering Documentation about it. The upright case has a full metal cover, space for a cooling fan and a shelf which can hold the rectifier board and electrolytic caps.  The bottles aren't U.S. types, they're Phillips equivalents with graphite plates.  They should hold up for a long time.  I'll use Chinese Coleman-type lantern chimneys. There's a good discussion over on eham about high power tubes, gettering and other issues. Unlike receiving tubes with their shiny flashed getters, high power tubes often use the anode or a coating as the getter, and need to operate at high temperature to work. Lots of good info out there free for the download. W5JGV's site has info from Eimac, RCA, Taylor and other tube makers. Not just the usual number and data but application notes, recommended practices, etc. Yes, but they want you to *buy* the stuff! My adapters were made from scraps. Some of us would have to buy stuff in order to have scraps. Bwaahaahaa  I've found that the hobby shop stuff is not terribly expensive.  They also have round, square and sheet plastic stock.  Some is clear and some is translucent--ideal for making dial scales. See description, above. I gotta take more pics... Exactly. Wood prices have changed, though; today a tabletop might be AC plywood. Depends what's on the cull cart. I don't have a place with a cull cart.  I've sometimes bought ugly-looking plywood and topped a desk with vinyl floor tile.  If you want to fancy one up, hardwood veneer isn't too pricey. Don't want fancy. Want functional. Thursday there was the remains of a packing box for some new furniture by a dumpster near here. The box was corrugated but the base was nice 2x4 and 1x6, nailed together. Cut off the corrugated and saved the wood. The former belongs in a museum, the latter in a home. Not everyone lives like us, Jim.  Some folks have houses large enough to be homes *and* museums and the wherewithal to populate the place with both types of antiques. Yep, you're right. Particularly around here!  I can appreciate antiques as art but we don't have enough room for antiques we can't put to use unless they happen to be art for the wall or items which can sit on a table for the most part. Same here. All about multiple uses. You're a lightweight!  My main operating position is representative of overkill.  The frame is 2x4's; the legs are 4x4's and the top is a hollow core door.  There's a two shelf console with two angled wings, with enough roof under the first shelf for solid-state brick VHF/UHF amps, keyers, paddles, DVK and the like. For me that frame is overkill but the hollow-core door is underkill - not strong enough. Did I mention the six foot rack to my right? I've had table racks but always wanted a six or seven foot floor rack. My old Handbook has plans for a wooden one... I did one table with a hollow core door many years ago (it was free) but they are too flimsy and too expensive for TSS approval now. They hold up well with the 2x4 frame and 2x4 bracing. Yes but that's not the issue. You can punch right through the surface with something sharp and heavy enough. The shack table in the website picture was designed for Field Day use, 25 years ago. The top was the maximum size that would fit in the back of a VW Rabbit with the rear seat taken out. All the legs and braces are bolted on in such a way that the whole thing breaks down into one package. Does the job for now but a replacement is in the works. Mine will break down too, but I don't think it'll fit in a Rabbit. :-) Less than 10 minutes to set up or take down, no tools needed. It's all about multiple uses. No card-tables on FD for me. 73 de Jim, N2EY |
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