The high current capability of the TV Sweep Output tubes allows one to use inexpensive output transformers with excellent results (low primary impedance).
And you can afford to toast a few cheap TV tubes while designing/testing your amplifier, no big deal. Fun finding tubes off Epay or Ham radio meetups too.
And you can afford to toast a few cheap TV tubes while designing/testing your amplifier, no big deal. Fun finding tubes off Epay or Ham radio meetups too.
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Proven with photos and confirmed by another forum member that it exists. There must be the topic where the only members can write, post and discuss the schematics, observations, suggestions and other non-trivials of use etc, imo will weed out lots of nonsense.
Looks like 4P1L to me. I'm not fan of russian tubes, but this one was a Wehrmacht's copied prototype. Whoever German guy worked on it looks was having that "assignment to create The Ever Best One". .. and almost succeeded.
How glad you Statesians are to have these cheap Compactron tubes! I envy you dearly, 'cause here in Europe they, and especially their sockets, are very scarce and rare, not to say almost unobtainable.
Btw, here are some pics of a set of rather powerful monophonic amplifiers I've built about 15 years ago. They make use of typical European sweep tubes.
Best regards!
Btw, on the 1st pic you see both mono amplifiers next to the left edge. In the lower right corner there's another amp of mine using PL519's. I've built this one very similar to a tehcnical bulletin that I've found at Svetlana's web site.
The 2nd pic sadly doesn't show any amp at all. Thiy simply was me about 13 years ago.
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Khe-m. Us, Canadians, by being the neighbor, snitch some TV Compactrons out and bootleg 'em over the border. I recently got a sleeve and tinkering on these.
In fact, the very good quality Compactron sockets are being produced in China nowadays, closer to you than us. I buy regularly from GD-parts on evil-Bay.
smoking-amp, have yo looked at the KT150? https://www.newsensor.com/pdf/tungsol/kt150-tungsol.pdf
12 pin compactron china sockets seem to work fine with me...
9 pin types are tricky, some can fit the thin pins while all will fit the thick pins,
and once you stick in the thick pins, then you can not use them for thin pins anymore...
i buy them in quantities and match them with my tubes..
if you are into tube rolling, i will not recommend china sockets...
but then what are the alternatives that comes to china sockets in terms of costs...
9 pin types are tricky, some can fit the thin pins while all will fit the thick pins,
and once you stick in the thick pins, then you can not use them for thin pins anymore...
i buy them in quantities and match them with my tubes..
if you are into tube rolling, i will not recommend china sockets...
but then what are the alternatives that comes to china sockets in terms of costs...
I second to Tony, then what are the alternatives? The 40-50 year old ebony ones?
Do not make my shoes laughing )) the Chinese-made are _ceramic_ and built like a brick.
The 12-pin worked very well to me too, but the Compatron-enveloped Novar-Magnoval messed ones. .. that's where the hell begins, I think that's what you r referring to.
Not non-fixable though. I posted my experience on making the OK Novar from Magnoval bases and Compactron terminals (seems been approved by smoking-amp).
Do not make my shoes laughing )) the Chinese-made are _ceramic_ and built like a brick.
The 12-pin worked very well to me too, but the Compatron-enveloped Novar-Magnoval messed ones. .. that's where the hell begins, I think that's what you r referring to.
Not non-fixable though. I posted my experience on making the OK Novar from Magnoval bases and Compactron terminals (seems been approved by smoking-amp).
Kay Pirinha's amplifiers look really nice.
Mine consist of Pete Millett proto boards strapped together on a wood plank.
Here one day, gone the next. Well, I did order a bunch more proto boards from Pete recently, maybe less transient now. I picked up one of Pavel's auto bias boards too, can make a real amplifier now.
Yeah, the 12 pin Chinese compactron sockets seem to be OK, they just can't seem to put those same socket pins into the 9 pin "Novar/Magnoval" sockets. I guess the Magnoval ceramics need to be a little tighter to hold the smaller pins firmly.
That KT150 looks real nice, but $70. Ouch !! Oriented toward higher plate B+ and Vg2 I think, 275 mA max DC. The 6HJ5 gets you to 280 mA DC for $4. 40KG6 gets you 500 mA DC. Of course, you pay for that in heater power.
Mine consist of Pete Millett proto boards strapped together on a wood plank.
Here one day, gone the next. Well, I did order a bunch more proto boards from Pete recently, maybe less transient now. I picked up one of Pavel's auto bias boards too, can make a real amplifier now.
Yeah, the 12 pin Chinese compactron sockets seem to be OK, they just can't seem to put those same socket pins into the 9 pin "Novar/Magnoval" sockets. I guess the Magnoval ceramics need to be a little tighter to hold the smaller pins firmly.
That KT150 looks real nice, but $70. Ouch !! Oriented toward higher plate B+ and Vg2 I think, 275 mA max DC. The 6HJ5 gets you to 280 mA DC for $4. 40KG6 gets you 500 mA DC. Of course, you pay for that in heater power.
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I just got in one of the rarest (and probably most useless...) tubes ever. The GE 7763 tube. Been searching for it for 15 years, this was the 1st time Google found something on it, and it was on Ebay. It's a beam deflection tube (BDT) with high (pentode like) gain. As far as I know, only evaluation prototypes were ever sent out by GE, but it came in a Mil spec box, so maybe some radio ended up using it. Could do the same function now with a $5 6JH8 TV tube and some JFET cascodes above the plates, but this was back in the 60s when it came out. If transistors hadn't come out, this would likely have been widely used in the IF strip of FM and AM radios and TVs. Hams used the 6JH8 for SSB generation. (single side band)
I'm trying to work out some way to curve trace some (differential) plate curves for it (like 6JH8 has on its datasheet). Likely hi-Z xfmr input and output. Once I succeed in that, I'll send it off to some tube museum I guess. Although, it could be used as the high gain differential front end to an all BDT (bank of 20 or so of 6JH8, 3 Watts + 3 Watts per tube) one of a kind amplifier. These BDT tubes are quite linear. I got a box of 6JH8 back in the Sale days.
http://tubedata.milbert.com/sheets/201/7/7763.pdf
http://tubedata.milbert.com/sheets/093/6/6JH8.pdf
The 6JH8 functionally looks like two low Mu (6) triodes above a CCS tail. The 7763 functionally looks like two pentodes above a CCS tail.
I'm trying to work out some way to curve trace some (differential) plate curves for it (like 6JH8 has on its datasheet). Likely hi-Z xfmr input and output. Once I succeed in that, I'll send it off to some tube museum I guess. Although, it could be used as the high gain differential front end to an all BDT (bank of 20 or so of 6JH8, 3 Watts + 3 Watts per tube) one of a kind amplifier. These BDT tubes are quite linear. I got a box of 6JH8 back in the Sale days.
http://tubedata.milbert.com/sheets/201/7/7763.pdf
http://tubedata.milbert.com/sheets/093/6/6JH8.pdf
The 6JH8 functionally looks like two low Mu (6) triodes above a CCS tail. The 7763 functionally looks like two pentodes above a CCS tail.
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For those who still fear the silicon.....these tubes make easy and very good CCS's.
A 3rd number to look up....the 6AR8. I found a loose (unboxed) one of these in a box of assorted tubes that I bought for $10 at a hamfest. It sat on my workbench for at least a year before I looked it up. I wired it up and it makes a good 5 mA CCS with less than 50 volts across it.