malfunctioning voltage regulator?

[rkc7]

I recently assembled a power supply for my active crossover and I used a design from here:

http://ldsg.snippets.org/FILTERS/Pomann/kitsupply.htm

Anyway, the +15 lead reads just under 15V, but the -15 reads -19.5V. I checked over everything, and it seems correct, could this be due to a faulty voltage regulator? The regulators are 7815 and 7915. Thanks.

 

[johnnyx]

I would check for a short between the IN and OUT on the 7915. I've had that a few times. The pinout of the 7815 & 7915 are different; if you didn't use the PCB, check that from the data sheets. If there is a reverse - biased diode between IN & OUT , check it's the right way round.

Hope this helps.

 

[peranders]

If you are using 79xx, are you aware of that the negative regulator doesn't have the same pinout as the positive 78xx?

 

[moamps]

Anyway, the +15 lead reads just under 15V, but the -15 reads -19.5V.

Hi,
negative regulator doesn't work properly without any load. Put some resistor (ca 1k) to output and check once again.

Regards
Milan

 

[rkc7]

Thanks Moamps, I guess it was fine, just needed a load. It's measuring correctly now. And yes, I knew the pin configuration was different, and everything was correct on the board, that's why I was confused. Thanks to all.