I'm 51, you?
Why not to consider compactron tubes? there is a large stock of them, with very interesting characteristics and many of them are cheap.
Why not to consider compactron tubes? there is a large stock of them, with very interesting characteristics and many of them are cheap.
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Yes, there's also a Compactron triple triode that actually is three halves of a 12AX7. I've seen it in some Fender amplifiers of the 1980ies. Sadly I don't remember it's designator and I also don't know if it is cheap enough 😱.
Best regards!
Best regards!
6AC10. A 12AX7 and half at a single heater powering cost. Excellent. And combinations of 12AU7´s and 12AX7´s in single envelope, like 6U10.
Not exactly, Osvaldo! IIRC there's a Compactron triple triode with a µ of 100 for all sections.
Best regards!
Best regards!
I am 60 that's why when you call me boy I felt good....lol....I am not familiar with compactron tubes but I will consider use them in future....all the best
interesting project, I would use KSC1845 for U3 - U12 and the follower positive supply to + 40v with a dropping resistor (10k) and capacitor.
Much easier to implement, tube sound comes from the gain stages
Much easier to implement, tube sound comes from the gain stages
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I think I'll have to dig out the schematics of the Fender amplifier that I mentioned. Then I can tell the one-and-a-half 12AX7's designator for sure 😉.
Best regards!
Best regards!
6C10 from the below table. But it is expensive. Less used triple triodes or double triodes plus diodes (6B10, 6AG11) and double pentodes are very useful. 6BF11 is a pretty pentode/tetrode combination, and has a very interesting hysteretic behavior in the pentode's screen and suppressor grids:
Delayed relay pentode driven
Delayed relay pentode driven
Thanks, Osvaldo, this is the tube!
Have I told you yet that I'm not that familiar with compactrons, as they aren't exactly familiar in Europe? I regard that as a pity, as they apparently are really interesting tubes. Oh, and they look sexy, too 😛.
Best regards!
Have I told you yet that I'm not that familiar with compactrons, as they aren't exactly familiar in Europe? I regard that as a pity, as they apparently are really interesting tubes. Oh, and they look sexy, too 😛.
Best regards!
OK. It is intriguing for me why European manufacturers didn't adhere to the compactron idea. It is very useful.
They went another way: Keeping B9A/Noval for small signal and low power tubes, swapping for Magnoval for higher power ones when International Octal went out of fashion.
Big tubes like PL519/40KG6A per manufacturers' advice need to be prevented from falling off their sockets. I guess this wasn't necessary for Compactrons due to three additional pins and a superior diameter to height ratio?
As said several times: It's dissappointing, at least for me, that Compactrons never were common here, hence aren't that easily to acquire, for not to speak on one Euro lists 🙁.
Best regards!
Big tubes like PL519/40KG6A per manufacturers' advice need to be prevented from falling off their sockets. I guess this wasn't necessary for Compactrons due to three additional pins and a superior diameter to height ratio?
As said several times: It's dissappointing, at least for me, that Compactrons never were common here, hence aren't that easily to acquire, for not to speak on one Euro lists 🙁.
Best regards!
Although the outline characteristics are different, the real advantage is inside the glass. There are some uncommonly high pentode, like the one designed for TF video IF with 30mS of transconductance, triple of the EF183/4 pair. Don't being remembering now the part name.
In Europe there were for video amplifier services the tubes PFL200 (21 mS), PCL200 (28 mS) and PL802 (40 mS) as the final developments. Televisions with them usually had pictures with more contrast than those with their predecessors (PCL84, PL83). Especially PCL200 is an interesting tube, as it's triode exactly is half a 12AT7. PL802 has become scarce and expensive for some time, but seems to be available again nowadays for decent money.
Best regards!
Best regards!
Sorry, I never saw them here.
I read several weeks ago that Zenith or General Electric has developed a dual compactron set for AM table radios, one with converter and FI, the other, audio pre and output, and the diode. And there?
Multi-Function Compactrons Promise Two-Tube Radio | Electronic Design
and others.
I read several weeks ago that Zenith or General Electric has developed a dual compactron set for AM table radios, one with converter and FI, the other, audio pre and output, and the diode. And there?
Multi-Function Compactrons Promise Two-Tube Radio | Electronic Design
and others.
I found the site where I learn about the two compactron radio set. here is it:
Compactrons: Advance in Tube Design, October 1960 Electronics World - RF Cafe
I have a friend here in Argentina that in the 70's, working for General Electric, made the service manuals in Spanish for this radios.
Compactrons: Advance in Tube Design, October 1960 Electronics World - RF Cafe
I have a friend here in Argentina that in the 70's, working for General Electric, made the service manuals in Spanish for this radios.
The Blonder-Tongue Audio Baton replica on the way, I just finished one channel and test it.
I stick to the original schematic but I add a 5 led bar graph, led VU meter and an unusual power supply that works very well.
The second channel will be upside down for fit inside a 3U cabinet and when finish will looks as the picture of the front panel. Both channel will be completely independent.
Sound is excellent just some minor noise issue but I will work out on it, this is just the first test.
All the best to everybody.
I stick to the original schematic but I add a 5 led bar graph, led VU meter and an unusual power supply that works very well.
The second channel will be upside down for fit inside a 3U cabinet and when finish will looks as the picture of the front panel. Both channel will be completely independent.
Sound is excellent just some minor noise issue but I will work out on it, this is just the first test.
All the best to everybody.
Attachments
Have you managed to tame that switcher? I have the same one in the junkbox but it is quite noisy