I'm an old guy, just getting into building my own tube amplifiers. I've been rebuilding speakers for awhile, and I've repaired a couple old tube-based reel-to-reel tape decks, but I felt the itch to do some tube amp stuff.
So far, I have build a stereo tube amp based on the 117N7GT tube and another around the 12 AU7 and 12K5 tubes.
I am slowly learning how to build from a schematic, and as time progresses, I have been teaching myself how to recognize what should go where and even to understand the math behind the values of the various resistors and capacitors; I have a long way to go and no illusions that I'm any kind of expert. At the moment, I know enough to read a schematic and build it and have music come out (mostly).
Anyway, felt I should introduce myself. I've been reading for awhile, just now getting to the point where I feel like speaking.
So far, I have build a stereo tube amp based on the 117N7GT tube and another around the 12 AU7 and 12K5 tubes.
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An externally hosted image should be here but it was not working when we last tested it.
I am slowly learning how to build from a schematic, and as time progresses, I have been teaching myself how to recognize what should go where and even to understand the math behind the values of the various resistors and capacitors; I have a long way to go and no illusions that I'm any kind of expert. At the moment, I know enough to read a schematic and build it and have music come out (mostly).
Anyway, felt I should introduce myself. I've been reading for awhile, just now getting to the point where I feel like speaking.
Welcome to the forum! 😀 And I am delighted to see a power transformer in that 117N7GT based SE amp!
And a fuse! I used a Triad N-68X at first, but I noticed that it puts out a trifle more than it takes in (I was measuring 140 VAC on the secondaries, and my house voltage is about 124 VAC), and it was getting hot; so where the output transformers. Found a step-up transformer that I had laying around, turned it around. I now have about 90 VAC on the B+, which might be a bit low, but I'd rather do that than put too much through it. Transformers are all now nice and cool. Next step is to bypass the built-in rectifier and do a bridge with some smoothing R-Cs and put it in a chassis and make it tidy. Sounds pretty good, for what it is. Nothing great, but really not too bad at all.
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