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After literally months of no activity since I did the heater wires, I finally have an afternoon to work on more stuff. (Yeah, mea culpa!) I followed the instructions and connected all the chassis stuff, so now I'm doing the turret board.

1) The second capacitor on the preamp end of the board (parallel with the 820 ohm resistor) is supposed to bea a 47uF 50V orange capacitor (per the pics). There is NOT one of these in the kit. The closest thing I can find in the kit parts is a 50uF 50V capacitor (black and silver like some of the others). I can't see anyplace for a 50uF cap, so I'm wondering if this is a substitute or my kit is missing a part?

2) At the power amp end of the board, there are supposed to be a pair of Xicon resistors, each in parallel with a 220 uF 50v capacitor. One is a 250R 5W. This one is in the kit. It's the one that goes parallel with the last cap on the board. The other is parallel with the second last cap and it's supposed to be a 125R 5W. This is NOT in the kit. There is a 150R 5W Xicon resistor that doesn't seem to go anywhere else. Again, is this another case of a "close enough" substitute, or am I missing a part?

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The 50uf 50 v is "close enough" - not sure enough about the other issue to say for sure.

Thanks for the input. Hopefully, one of the forum experts answers the other one.

Tough call on a Sunday.

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Another question.

3) There's supposed to be a polarized 22uF cap that's also on the preamp end of the board. Looks like it attaches to pin 3 of v2. There isn't such a capacitor in the kit parts. I do see a polarized 25uF cap that doesn't seem to go anywhere (I think). Again, is this another case of a close enough substitution or am I missing a part?


I'm a bit confused because a lot of the components seem to be 5% or even 10% tolerances. A 25uF cap is outside both tolerances for a 22uF part. Besides, that's at nominal. The 25uF cap actually measures 26uF on my meter. Am I missing parts or should I simply be going with the flow and using the stuff that seems close? I don't want to screw up and have to tear things down and re-solder later.

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IIRC eectrolytic caps are often 20% tolerance. And the difference between 22uF and 25uF isn't something you can hear. Generally, 22uF and 25uF are considered to be pretty much the same thing - same with 220uF and 250uF or 47uF and 50uF.


No, it's actually meant to be 150R as stock. Trinity changed from 125 ohms to 150 ohms, to bias the tubes into a safer operating region, on my advice.

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Great tones come in small glass jars!

Awesome. So as I read it, it's pretty much the same effective answer for all three of my questions. I'll use the parts I have!

1) The 50uF is close enough to the 47uF on the layout, so I'll use it.

2) The 150R at the power end isn't just "close enough", but rather a revision based on input from zaphod. Good news. It would be cool if Trinity updated their drawings, but maybe they have since I bought the kit.

3) Teh 22uF cap is close enough to the 22uF called out on the layout, so I'll use it.

Thanks to both people that replied on a Sunday afternoon. I was afraid of light traffic on the board, but a little GOOD traffic is enough! Many thanks.

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Go Buckeyes!