I have just got a second hand power supply from eBay and it's working fine, except I see a some mild noise on my monochrome monitor (it's a standard VGA monitor with an adapter). It's most apparent on the grey desktop (due to the 50% grey pattern I suppose).
I should explain that I'm running a 520 STFM motherboard with TOS 1.0, encased in the steel chassis but without a floppy drive - I bought it for the ram chips but found out it was all OK and decided to resurrect it with a 4MB memory upgrade (just bought some SIMMs for this) and a home made case. I have another STFM here that I previously upgraded to 1MB RAM and I borrowed the power supply from it to try with the bare motherboard. The picture was rock solid, so I am suspecting that the power supply I bought from eBay is not quite 100%.
It says its model number is ASP34-2 (on a stuck-on label) and the board has REV.3 silk-screen printed on it, as well as an Atari logo and "C100000-001 GX-211 VO" and some dire warnings about the internal fuse
. Otherwise it looks like a bog standard STFM power supply.
So to the question (and please note, I have searched but - well, let's just say the forum search here isn't the best
):What's the best way of cleaning up the output from this power supply? Capacitors, I imagine, but which ones?
I'm thinking C5 (the one with the big red label warning that it is connected to the mains) which looks to be 47uF @ 250v. There are other similar sized (I mean in terms of dimensions, not capacitance) electrolytics on the board as well. Which ones are the most likely culprits?
Too many retro computers here: 1040STfm, Mega4, Ultrasatanx2 , Amiga A500, A500+ and A1200, Acorn Atom x2, BBC Micro, Electron, Spectrum 48k x2, +48, +128k, QL, Oric Atmos, ZX81, Memotech MTX512, Amstrad 6128 x2..