Custom power transformer & snubbing caps

[Samuel Groner]

Hi
Two questions regarding my PS design for a 5-into-2 mixer with powerful headphone amp:

a) is there a company that will do a (actually one...) custom toroid like this: 2x115 V prim., 2x30 V & 2x21 V sec., electrostatic (Faraday) and magnetic shield, around 50 VA. I found some companies in USA/Canada, but I would prefer one in Europe. Anyone knows about www.teca.net? Any good?

b) is it OK to use 10 nF ceramic (X7R or COG) for snubbing caps (caps parallel to the rectifier diodes)? I just don't have space for film...

Thanks for any input!
Samuel

 

[gyraf]

Ulveco, Denmark:

http://www.ulveco.dk/default.asp?lang_id=2057

I use them for all sorts of prototype transformers. Extremely high quality, very competent designers, and reasonable pricing.

Jakob E.

 

[Samuel Groner]

Thanks for the answers so far!

But it would be much easier to help you and to name some companies if you had typed in your location

Switzerland.

Samuel

 

[Samuel Groner]

reasonable pricing

Can you give me a very broad idea what the price will be for the xfm I have specified?
Samuel

 

[thermionic]

I can only speak from experiences with Power amps, but I've had no problems with high-voltage ceramic caps as snubbers on rectifiers, whereas I have seen poly-types explode quite spectacularly after a few years of use.

ILP: http://www.applegate.co.uk/elec/company/co_7797.htm will make you a custom toroid in the UK.

Antrim are my favourite on account of their zero-mechanical-noise design, but I'm not sure they'll make a one-off, you could always try them, price is usually good: http://www.antrimtransformers.com/

Justin