watt finally builds an amp (results TBD)

Wntrmute2

Not So Mediocre Member
Thanks for looking, gable.

I wouldn't say I'm 100% confident in any joint soldered to those strips (I found that these didn't take the solder very well, and the holes are really big to fill), but I just shone a light on those, and I think you're seeing reflection. They're full, and the wire's in there pretty good. Still, that is the 6.3V winding, so it couldn't hurt to touch it up. I'll do that.
I've had trouble with those strips occasionally. Sometimes the are fine other-times I struggle to get a decent looking solder joint. I have since moved on to those ones in my pictures above. AES has them.
 
Also, I can't seem to find where your recitifier's filament is tied to one leg of the anode. I could just be missing it in there.

I'm not sure that I understand, though I'd like to.

I registered some confusion about the rectifier connections in post 43. Redboy answered in 46, and I thought I understood what to do after that.

Pins 6 and 4 (anodes, yes?) connected to HT winding, 8 and 2 connected to the 5V winding, with one leg of the filament also connected to the choke and C1.
 
I'm not sure that I understand, though I'd like to.

I registered some confusion about the rectifier connections in post 43. Redboy answered in 46, and I thought I understood what to do after that.

Pins 6 and 4 (anodes, yes?) connected to HT winding, 8 and 2 connected to the 5V winding, with one leg of the filament also connected to the choke and C1.

Oh, I mis-spoke, my apologies!

After a better second look, you have that wired correctly, per the schematic.
 
I think I still have a little work to do tuning the power supply, but I've been using this amplifier on and off for the past week. With the Slagle AVC in front, playing through a pair of 605Bs, it's really enjoyable. Great tone. Surprisingly good extension.

P1020306.JPG

Have I forgotten about the Line Magnetic 300b that's sitting on the floor across the room? No. But this project has given me a sense of the satisfactions that can come from building a tube amp. I get it now, and I think I'll do it again (he says, knowing that there's a pair of Acrosound outputs on a shelf in the closet). But first I'm going to listen to this one for awhile longer. It does sound good.

I appreciate the help and encouragement that you all offered along the way. Big thanks to Redboy, who answered my PM'ed questions without telling me to put a sock in it.
 
I know. I bought them a year or so ago, really without to clue as to how I'd use them, to force myself to finally try to build something.

Coming soon to a thread near you . . .
I know that game.

I bug @gable far too often with questions about what's what. Thankfully, there's a kind of person called a friend and they put up with that stuff.

Congrats on the build!
 

ColinWonfor

Junior Member
This bring back memories with my Granddad, when he showed me how to build valve kit.
One was the PSU supply, the inductor/choke at 50 and 60Hz is massive, we/he used multiple voltage doubler circuits after the main HT transformer, so as you double the voltage you also double the frequency of the ripple thus reducing the choke and bulk capacitors needed. I wondered has anybody tried that here?
So with a secondary winding of 150VAC it was easy to get to the working voltage he needed.
If I can I will dig out is log book and put up his circuits and calcs.

Radio Ham books are a great source of good solid information. There was some in PDF form on www.archive.org check it out. (oh and some nice music)

Yours

G8XIV
 
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