On the new revision card with the C6, is this capacitor necessary or is it optional if you run the card single rail?
I can see this card is a jack of all trades. I won't be running any external feedback into it.
Also, can I just short the varistor, again running card as single rail?
I can see this card is a jack of all trades. I won't be running any external feedback into it.
Also, can I just short the varistor, again running card as single rail?
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Have you read Nelson's post #686 yet?
He said that R13, R14, P1 and C6 are optional, and he explained their purposes. It has nothing to do with whether the power supply is bipolar or single ended.
If you do not need the add-ons, omit all of the optional parts. The only location that needs a jumper would be at R13. P1 (not a varistor by the way, it is a trimmer or potentiometer) does not need jumpers, but do install R6.
I have the original with none of the latest options and it sounds great. 🙂
He said that R13, R14, P1 and C6 are optional, and he explained their purposes. It has nothing to do with whether the power supply is bipolar or single ended.
If you do not need the add-ons, omit all of the optional parts. The only location that needs a jumper would be at R13. P1 (not a varistor by the way, it is a trimmer or potentiometer) does not need jumpers, but do install R6.
I have the original with none of the latest options and it sounds great. 🙂
OK, I got the hammers and nails part. R6 INSTEAD OF trimmer. R13 jumpered, C6 only if needed but not jumpered, R14 only if some kind of feedback is taken from downstream, just leave out.
Thank you.
Thank you.
R10 is jumpered if the supply is V+, and V- becomes Ground.
R9 is jumpered if the supply is V-, and V+ becomes Ground.
R9 is jumpered if the supply is V-, and V+ becomes Ground.
FE essential kit also arrived here. Thanks Papa!
I think I'll go for fixed R6 and 50V (dual 25-0-5, single?) PSU.
I think I'll go for fixed R6 and 50V (dual 25-0-5, single?) PSU.
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I stuffed the resistors, placed and soldered the transistors. Is there anything more nerve racking than soldering all those tiny leads on 14 transistors and wondering if you blew it somewhere? I tested connections as best I could.
Just about the time I got the last transistors soldered was the time I finally got my technique down.
Waiting for caps to arrive then bench testing to see if they work. I will be running it single rail, so also placed the jumpers across R10 and R13, and placed R6 instead of pot, and will observe the polarities printed on the boards.
Just about the time I got the last transistors soldered was the time I finally got my technique down.
Waiting for caps to arrive then bench testing to see if they work. I will be running it single rail, so also placed the jumpers across R10 and R13, and placed R6 instead of pot, and will observe the polarities printed on the boards.
Is there anything more nerve racking than soldering all those
build Mrk Lvinson, then think of same question
or at least Elctrcmpaniet
logic being - why not dozen instead of one?

What? Nerve racking soldering? Get yourself a proper worklight with magnifying glass. Those are worth much more than their weight in gold 🙂👍
I actually use one of those headband 'stamp collector' types - they relatively cheap, not exactly professional fitting, but do the job very well - I'm currently looking at those "Vision Aid" ones with the included led light at about A$60.
I find the 'work-light' magnifier a bit clumsy with larger projects, but perfectly okay for small ones - the more recent led versions far better than my old fluoro tube one plus an adjustable "Planet lamp".
I find the 'work-light' magnifier a bit clumsy with larger projects, but perfectly okay for small ones - the more recent led versions far better than my old fluoro tube one plus an adjustable "Planet lamp".
I have a table lamp almost identical to the one pictured and also this loupe for finer work. Both together aren't expensive.
Just wanted to know, can I use this torroid for the FE PSU?
planning to install this in the chassis.
https://www.digikey.com/en/products...5721753?s=N4IgTCBcDa4MwHYC0YAMcAsSByAREAugL5A
planning to install this in the chassis.
https://www.digikey.com/en/products...5721753?s=N4IgTCBcDa4MwHYC0YAMcAsSByAREAugL5A
I used a Triad transformer in my build too, except I went with the less costly VPT series. The difference is that it doesn't have the flux band of the VPM series. However I do not hear any audible noise through my 103dB speakers and the noise measured quite low in the FFT measurements.
My build and FFTs: My build, FFTs
My build and FFTs: My build, FFTs
How much gain did it end up with? will it drive an F4?Yes. That is what I am using. But my line voltage is 120VAC.
I was waiting for this questionHow much gain did it end up with? will it drive an F4?

Works well with my F4. More gain than I can use.How much gain did it end up with? will it drive an F4?
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