[phidauex]

So where do you guys get parts for power supplies? Digikey.com seems to have a moderate selection of transformers and caps, but nothing very 'wild'.

My reasons are slightly off topic, but its something many of you may be familiar with. I'm going to build an n-channel MOSFET amp for speakers (speakers are like headphones, except they are much larger, and you put them in the corners of a room, instead of on your head, oh yeah, and you don't need crossfeed circuits, for some reason) But it needs a +-70VDC power supply. The transformer has to be something like 500VA, and have two 50V secondary windings. Digikey doesn't seem to sell anything like this... Also, I need about 40,000mfd of capacitance filtering on each rail, is it better to use several parallel 10,000mfd caps, or one 40,000mfd per rail? Where is a good place to get such things? Digikey has a few large caps, but they are all part of Panasonic's 'T-UP' snap-in series.

Basically what i'm looking for is a 'power supply parts R' Us' kind of place, any ideas?

peace,
phidauex

 

[Magic77]

You can try; Newark Electronics(newark.com). Allied Electronics(alliedelec.com). Mouser Electronics(mouser.com).

I don't know if they have exactly what you need, but they are some of the bigger suppliers.

 

[Phloodpants]

http://www.diyaudio.com/forums/

 

[Possum]

You can get the large transformers directly from the manufacturers like toroid.com and plitron.com for the toroidial-type transformers used by many amp builders. I usually (EDIT) "see" DIY'ers using a few capacitors paralleled rather than one large capacitor, and that's what I would do.

 

[phidauex]

Thanks for the responses guys

Looking at some of those links, I think the transformer will probably come from toroid.com's kits. They have quite a few kits, at reasonable prices.

Still not sure about the capacitors though. I know its worth it to get nice ones, but something inside me cries out at the idea of paying 30-40$ or more for a single capacitor

Oh well, quality has a price, eh?

peace,
phidauex

 

[Possum]

You're comfortable winding your own transformers?

That would be too painful and tedious for me.

 

[phidauex]

Well, the problem is that I need a very large, very specific transformer.. at least 500VA, with a 117V primary winding, and 2 independent 50V windings. i haven't found anything out there with those specs. My options for now are to keep looking, cause i'm sure a transformer like that is out there (but if its special, i'll have to be willing to pay for it!), or to have someone custom make me one, which would be more expensive than the kit.

I'm not a big fan of slow and tedious, but I've got a steady hand, and it would be an interesting project to wind up a transformer

They come with the 117V primary winding already done, you just need to wrap up the other windings to your specs, then case it up, and enjoy

the caps are another issue.. cost may force me to go with large panasonic caps.. their specs aren't GREAT, but i'm not sure if i can afford nice elnas right now

peace,
phidauex