Don't try this at home. (way too long) - PeterP - Tube DIY Asylum

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Don't try this at home. (way too long)

In Reply to: Re: KT88 amp posted by Tubefever on October 1, 2002 at 05:45:22:

DON'T LET THIS HAPPEN TO YOU.
The power supply was a carry-over from the breadboard. I found that a B+ of about 400V sounded best however the transformer is a 370HX (550V ct @ 200mA) so I pushed it. My line runs around 126Vac which I ran on the 110V tap (NOT the 120V). With ss diodes and filtering (CLC) you get a B+ of 410V. The added benefit was now I could use the 5V (Now 6.2V @ no load) to run the front end 6SL7 and the other 6.3V (Now with resistors) to run the KT88/KT90.
For a breadboard that's fine. I'll run it that way for a couple of days, maybe a week or two. That was about a year and a half ago.
DON'T DO THIS!
I now have it apart again. This time I'm changing to 372JX (600V ct @ 250mA to get a proper 400V) and I want to play with the front end. First up will be a cascode amp with octals or maybe even try 76's. Next I'll try to get a LL1660/10mA IT to work. (I've had a pair for over a year.) Then I plan to select one design and turn it into a "real" amp.
Too many projects and too many things to try.
I will say that despite the abuse, the 370HX performed well. It really didn't run too hot and didn't hum/buzz. Lucky? Maybe. I have used the 200 series and will not use them for anything but breadboards. Way too much buzz.
Take care.
Pete.

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K&K Audio / Lundahl Transformers

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Follow Ups Full Thread

Topic - Which SE output transformer for Fi Primer 6L6SE? - tubefever 12:52:09 09/30/02 (12)

JC's 6L6 SE - Jim Dowdy 14:23:04 09/30/02 (10)

1627SE has 40% taps (nt). - Morse 15:31:25 09/30/02 (9)

1627SE sounds good to me. - PeterP 19:04:44 09/30/02 (8)

Re: KT88 amp - Tubefever 05:45:22 10/01/02 (1)

Don't try this at home. (way too long) - PeterP 18:28:42 10/01/02 (0)

Get the torches.... - Sector-7G 19:10:08 09/30/02 (5)

Yes. Forgive me for I have sinned ;^) - PeterP 19:40:56 09/30/02 (1)

Re: Yes. Forgive me for I have sinned ;^) - Sector-7G 06:50:40 10/01/02 (0)

Re: Get the torches.... - Andrewbee 19:24:34 09/30/02 (2)

Re: Get the torches.... - PÃ¤r 10:55:00 10/01/02 (1)

Burning Sulfur that is.... - Sector-7G 12:41:50 10/01/02 (0)

Re: Which SE output transformer for Fi Primer 6L6SE? - Morse 14:13:19 09/30/02 (0)

Follow Ups

Don't try this at home. (way too long) - PeterP 18:28:42 10/01/02 (0)

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