F3 Builders Thread

Get the biggest value caps you can fit.
You're limited to 35mm in diameter using the diyaudio store pcb.
The onboard cap multiplier does most of the filtering but I always go for the biggest that will fit. Sooner or later you might decide to build something else which might require bigger value uF caps.
You could also consider screw terminal caps and forget the pcb, united chemicon U36D or U32D are good value for screw terminal caps.
 
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Updated version of my boards. I think I'm about ready to try etching them, but I've got a couple of simpler projects lined up to experiment with first.

A couple of notes: I've posted low-res versions to save bandwidth. If anyone else want to try them, message me and I'll send you 600 dpi versions. Keep in mind though that these are simple graphic files suitable for toner-transfer home etching. They are not Gerbers. (I grew up in the days of tape and mylar, and you know the saying about old dogs and new tricks.)
 

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A question on the circuit:

D1 is there solely to protect Q5's gate from excess voltage as C5 discharges if the power supply is discharged faster. Is that correct? (In which case a 1N4007 will also work.)

Thanks,
Jeff.

PS: while I do have some 1N4007s on hand which prompted this question, it's really more about me starting to understand these circuits than about saving the $0.25 a couple of 1N4001s would cost me. ;)
 
I ended up making a few changes to the coupling cap arrangement (2 x 8,200uF electrolytics and 1 x 8.2uF polypropylene "jelly roll"), and added a bypass (10uF polyester) to C7. My PSU is also a bit different with 36V secondaries and dual mono construction. So I don't think "clone" really fits anymore.

I thought about "DIY F3", but I'm also trying to capture the aesthetic of the Firstwatt production units, and DIY doesn't suggest that to me.

How about:

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?
 

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I didn't mean DIY as pejorative. Rather to me it conveys a custom implementation, not just a non-series implementation. Sort of like doing a cover song, but as yourself.

Whereas I'm (shamelessly) copying the form-factor of the production implementation as well. More like doing a cover song dressed up as the original act. Which led me to "tribute act".

Cheers,
Jeff.