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Post by Night Ranger on Mar 7, 2017 21:39:38 GMT -5
I have acquired a setup for a future Classic Radio Roundup. I can't say I have ever owned a piece of equipment that gave me a sense of inner loathing just looking at it, but this one does. In any case it was a highly prized CB amp in the North Carolina/South Carolina area in the 1970s and early 1980s, and no trailer park or mill village was complete without one. Someone offered me one at a reasonable price, so I bought it just for one run on either Old Radio Night or Classic Radio Roundup for this summer. In any case depending on your point of view I present for your admiration or loathing my newly acquired six tube Elkin. Yes I am running a low pass TVI filter with it. On my Drake WH-7 water meter it is dead keying about 180 watts with four watts in. It uses six 12dq6b tubes.  I'm already planning to sell it once it has made it's videogate debut on CRR this summer. I'm also curious to see how wide banded it will be on Goatrider's SDR bandscope on Old Radio Night. Night Ranger |
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Sandbagger
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Post by Sandbagger on Mar 7, 2017 22:08:08 GMT -5
I have acquired a setup for a future Classic Radio Roundup. I can't say I have ever owned a piece of equipment that gave me a sense of inner loathing just looking at it, but this one does. In any case it was a highly prized CB amp in the North Carolina/South Carolina area in the 1970s and early 1980s, and no trailer park or mill village was complete without one. Someone offered me one at a reasonable price, so I bought it just for one run on either Old Radio Night or Classic Radio Roundup for this summer. In any case depending on your point of view I present for your admiration or loathing my newly acquired six tube Elkin. Yes I am running a low pass TVI filter with it. On my Drake WH-7 water meter it is dead keying about 170 watts with four watts in. It uses six 12dq6b tubes. I'm already planning to sell it once it has made it's videogate debut on CRR this summer. I'm also curious to see how wide banded it will be on Goatrider's SDR bandscope on Old Radio Night. Night Ranger Just make sure you don't sell it to a neighbor.......or someone in our neck of the woods.......  |
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Post by Night Ranger on Mar 7, 2017 22:14:14 GMT -5
I have acquired a setup for a future Classic Radio Roundup. I can't say I have ever owned a piece of equipment that gave me a sense of inner loathing just looking at it, but this one does. In any case it was a highly prized CB amp in the North Carolina/South Carolina area in the 1970s and early 1980s, and no trailer park or mill village was complete without one. Someone offered me one at a reasonable price, so I bought it just for one run on either Old Radio Night or Classic Radio Roundup for this summer. In any case depending on your point of view I present for your admiration or loathing my newly acquired six tube Elkin. Yes I am running a low pass TVI filter with it. On my Drake WH-7 water meter it is dead keying about 170 watts with four watts in. It uses six 12dq6b tubes. I'm already planning to sell it once it has made it's videogate debut on CRR this summer. I'm also curious to see how wide banded it will be on Goatrider's SDR bandscope on Old Radio Night. Night Ranger Just make sure you don't sell it to a neighbor.......or someone in our neck of the woods....... Look on the bright side. When the skip starts rolling hot and heavy this summer I can bleedover on channel 11 as bad as they are bleeding over on me on channel 13.  Night Ranger |
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Sandbagger
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Post by Sandbagger on Mar 8, 2017 7:11:34 GMT -5
Just make sure you don't sell it to a neighbor.......or someone in our neck of the woods....... Look on the bright side. When the skip starts rolling hot and heavy this summer I can bleedover on channel 11 as bad as they are bleeding over on me on channel 13. Night Ranger I wonder if those Elkin amps could be tamed by not overdriving them with an overmodulated splatterbox. Garbage in = garbage out. |
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Post by Night Ranger on Mar 8, 2017 7:27:35 GMT -5
Look on the bright side. When the skip starts rolling hot and heavy this summer I can bleedover on channel 11 as bad as they are bleeding over on me on channel 13. Night Ranger I wonder if those Elkin amps could be tamed by not overdriving them with an overmodulated splatterbox. Garbage in = garbage out. ...And changing the bias to class B or AB. I suspect they are grid driven instead of grounded grid. The datasheet for the 12dq6b/6dq6b tube shows the cathode and the supressor grid are internally tied together. I've read that makes the tube unsuitable for grounded grid use. Also there is no driver stage. It also looks like the output tank circuit may be push-pull. I have not had the cover off of it yet though, and this is the first Elkin I've had my hands on. 2600 can probably shed volumes of light on the Elkin amplifiers (nudge nudge => 2600).www.nj7p.org/Tubes/PDFs/Frank/093-GE/6DQ6B.pdfNight Ranger |
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Sandbagger
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Post by Sandbagger on Mar 8, 2017 10:23:48 GMT -5
I wonder if those Elkin amps could be tamed by not overdriving them with an overmodulated splatterbox. Garbage in = garbage out. ...And changing the bias to class B or AB. I suspect they are grid driven instead of grounded grid. The datasheet for the 12dq6b/6dq6b tube shows the cathode and the supressor grid are internally tied together. I've read that makes the tube unsuitable for grounded grid use. Also there is no driver stage. It also looks like the output tank circuit may be push-pull. I have not had the cover off of it yet though, and this is the first Elkin I've had my hands on. 2600 can probably shed volumes of light on the Elkin amplifiers (nudge nudge => 2600).www.nj7p.org/Tubes/PDFs/Frank/093-GE/6DQ6B.pdfNight Ranger 6146's don't work well in grounded grid either for the same reason. But yea, if the Elkin is biased class C, then it's going to be less than clean on the output. |
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Post by BBB on Mar 8, 2017 11:28:20 GMT -5
Regional amps, cool. Sort of like how I see a lot of D&As in the northeast and Varmints in the mid-west?
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Sandbagger
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Post by Sandbagger on Mar 8, 2017 11:45:06 GMT -5
Regional amps, cool. Sort of like how I see a lot of D&As in the northeast and Varmints in the mid-west? D&A's were not really regional, as they were make in Arizona... But I guess they had better distribution and marketing networks. |
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Post by Night Ranger on Mar 8, 2017 13:45:24 GMT -5
Regional amps, cool. Sort of like how I see a lot of D&As in the northeast and Varmints in the mid-west? D&A's were not really regional, as they were make in Arizona... But I guess they had better distribution and marketing networks. Nope. D&A's were made in Scottsbluff, Nebraska. It is written right on some of the D&A amplifiers as well as the accompanying paperwork. See the picture below.  Night Ranger |
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Post by Night Ranger on Mar 8, 2017 14:04:50 GMT -5
Regional amps, cool. Sort of like how I see a lot of D&As in the northeast and Varmints in the mid-west? There were plenty of D&A, Varmint, Palomar , and of course Elkin amplifiers around South Carolina and North Carolina in the 1970s and 1980s. There was one Kris amplifier I heard about and a few Pride mobile amplifiers. I don't remember hearing anyone run any of the Maco amplifiers back then. Night Ranger |
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Sandbagger
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Post by Sandbagger on Mar 9, 2017 7:54:20 GMT -5
D&A's were not really regional, as they were make in Arizona... But I guess they had better distribution and marketing networks. Nope. D&A's were made in Scottsbluff, Nebraska. It is written right on some of the D&A amplifiers as well as the accompanying paperwork. See the picture below. Night Ranger D'oh. My mistake. I confuse Scottsdale (Az) with Scottsbluff (Ne). Chalk that one up to age related CRS........  |
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Sandbagger
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Post by Sandbagger on Mar 9, 2017 8:00:47 GMT -5
Regional amps, cool. Sort of like how I see a lot of D&As in the northeast and Varmints in the mid-west? There were plenty of D&A, Varmint, Palomar , and of course Elkin amplifiers around South Carolina and North Carolina in the 1970s and 1980s. There was one Kris amplifier I heard about and a few Pride mobile amplifiers. I don't remember hearing anyone run any of the Maco amplifiers back then. Night Ranger I guess Elkin was like the "Dave made" of the day. Garage shop built and limited in distribution networks. Back in the 70's you could buy D&A, Palomar, ABC, Hy-Gain, Kris, HEC and others in mail order catalogs like Henshaws. And the bigger CB dealers had a back room full of the more popular amps as well. Elkin just never broke through to that level. |
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Post by 2600 on Mar 11, 2017 23:43:41 GMT -5
The Elkin amplifiers were built by a mad genius named Ray Felts in North Carolina. Can't remember the town right now. CRS again.
They are grid-driven. Reduces the radio power needed to do the job, and insures that every Watt of radio drive is used. Or misused.
Every batch of Elkins is different. There are no schematic diagrams to be had. Not sure he ever bothered to draw them up. The design would change every time he built more of them.
He used tubes that were cheap. When Varmint (Abe Brewer), D&A (Ed DuLaney) and Maco were all using grounded-grid circuits with (then) current-day tubes meant for color TVs, Ray was using tubes that had become cheap and were in reduced demand. The 6DQ6 and 12DQ6 were designed for monochrome televisions. When color became popular the demand for those tubes dropped off. The button-base 9-pin 6LQ6/6KV6/6JG6 tubes and 12-pin 6KD6/6LF6/6LR6/8950 tubes were designed for color television horizontal-sweep circuits.
I'm just assuming that when factories were still using the glass-button based tubes to build color TVs that the tubes meant to go in a monochrome TV were already being sold off cheap.
The 807 and 1625 military-surplus tubes that Ray used for a while would go for a quarter each in quantity in late 60s and late 70s/early 80s.
Ray's designs were unique among the non-legal amplifiers by using neutralization. A grounded-grid circuit limits the power gain of a single amplifier stage, making an internal driver necessary to get more than about ten-to-one more than the radio can drive into it. But a grounded-grid circuit trades high stability and simplicity for reduced power gain. Ray's grounded-cathode amplifiers would get a lot more power gain, but when you do this you have problems with feedback inside the tube that will cause it to oscillate. The neutralizing circuit fixes this, but adds complexity. Getting that neutralizing capacitor adjusted right would normally have to be done only if you changed the tubes from the brand it was built with to tubes made in a different factory. That, and all the tubes tied together in one amplifier had to come from the same vendor. If you mixed tubes from different assembly lines in an Elkin amplifier you might never get that neutralizing adjustment to achieve a stable setting. This also happens in ham radios that use a pair of sweep tubes for the final, like the Swan and Yaesu FT-101 radios. If you "pair" a tube made in Owensboro KY with a tube made in Japan in your FT-101 you will never get the neutralization to set properly. The setting for each tube is different, and you'll never get it set in two places at once.
Ray is still around, and must be close to 90 by now, maybe older. Last of his breed, far as I know.
73
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Post by Night Ranger on Mar 13, 2017 14:55:48 GMT -5
The Elkin amplifiers were built by a mad genius named Ray Felts in North Carolina. Can't remember the town right now. CRS again. They are grid-driven. Reduces the radio power needed to do the job, and insures that every Watt of radio drive is used. Or misused. Every batch of Elkins is different. There are no schematic diagrams to be had. Not sure he ever bothered to draw them up. The design would change every time he built more of them. He used tubes that were cheap. When Varmint (Abe Brewer), D&A (Ed DuLaney) and Maco were all using grounded-grid circuits with (then) current-day tubes meant for color TVs, Ray was using tubes that had become cheap and were in reduced demand. The 6DQ6 and 12DQ6 were designed for monochrome televisions. When color became popular the demand for those tubes dropped off. The button-base 9-pin 6LQ6/6KV6/6JG6 tubes and 12-pin 6KD6/6LF6/6LR6/8950 tubes were designed for color television horizontal-sweep circuits. I'm just assuming that when factories were still using the glass-button based tubes to build color TVs that the tubes meant to go in a monochrome TV were already being sold off cheap. The 807 and 1625 military-surplus tubes that Ray used for a while would go for a quarter each in quantity in late 60s and late 70s/early 80s. Ray's designs were unique among the non-legal amplifiers by using neutralization. A grounded-grid circuit limits the power gain of a single amplifier stage, making an internal driver necessary to get more than about ten-to-one more than the radio can drive into it. But a grounded-grid circuit trades high stability and simplicity for reduced power gain. Ray's grounded-cathode amplifiers would get a lot more power gain, but when you do this you have problems with feedback inside the tube that will cause it to oscillate. The neutralizing circuit fixes this, but adds complexity. Getting that neutralizing capacitor adjusted right would normally have to be done only if you changed the tubes from the brand it was built with to tubes made in a different factory. That, and all the tubes tied together in one amplifier had to come from the same vendor. If you mixed tubes from different assembly lines in an Elkin amplifier you might never get that neutralizing adjustment to achieve a stable setting. This also happens in ham radios that use a pair of sweep tubes for the final, like the Swan and Yaesu FT-101 radios. If you "pair" a tube made in Owensboro KY with a tube made in Japan in your FT-101 you will never get the neutralization to set properly. The setting for each tube is different, and you'll never get it set in two places at once. Ray is still around, and must be close to 90 by now, maybe older. Last of his breed, far as I know. 73 The output tank circuit appears to be push-pull as well. I have not taken the cover off yet, but it looks that way just from what I can see through the square holes in the cover. Night Ranger |
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