Quick question about power supply

[boy howdy]

My transformer specs as follows: PRI: 110-120V: 60HZ, 250VCT@25DCMA with a center tap, 6.3V @1.0A.

Can I use (2) IN4003 diodes instead of IN4007s? It's all Radio Shuck had.

Thanks, guys.

[Phil_S]

For 1N4003 voltage rating is 200V and RMS reverse voltage is 140.
There is a nice chart here: http://www.diodes.com/datasheets/ds28002.pdf
Your PT is 125-0-125, so it looks OK. Use 2 in series if in doubt.

What are you making with that PT? 25mA isn't much capacity.

[martin manning]

250 V CT means 125 VAC on each leg, peak is 1.414 times that or 177V. In a FW rectifier the diodes see 2x this peak voltage when reverse-biased so that's 354. 1N4003 is rated 200V repetitive PIV so in theory two of them in series would be okay. But I wouldn't do it. Two 1N4004 at 400V each would be fine.

[boy howdy]

I can never remember them.

On second thought, I think what I got was IN4004 or 6. I don't have them with me to check.

I do remember that they had peak reverse voltage of 600V. And a forward rectified current of 1A.

Does that work?

I'm building a one tube preamp.

Nice datasheet, Phil!