Need help identifing the value of a capacitor from a vintage Rotel RA1412 stereo amplifier.
It is brown 16x11x6mm and is marked:
.01K DT or D7
630 ST.S
It looks like a large orange drop capacitor.
Any help would be greatly appreciated.
It is on the power PCB for the left channel between the fuses and diodes connected to the main 22,000uf 63v capacitors for the left channel. The 2 fuses for the left channel are blown and the schematic trouble shooting guide says to replace these capacitors first. There are 3 of them in similar locations on the PCB. Trying to read the capacitor I could not tell if it was .01uf or .01pf. I suspected the 630 was for volts. I bought this amplifier new in 1976 and this is the first problem I've had with it. It's an old friend and I want to bring it back to life. Thanks.
Ok. You could measure (Ohm) the capacitors, but also the rectifier bridge, for shorts.
0.01pF doesn't exist so that one's easy, it's 0.01uF - and the size of it also corresponds with what I'd expect from 10nF 630V.
K is a tolerance symbol btw.
My vote goes for .01uF, 10 nF, 103 (same value - different name). I think your old friend is hinting that it wants new capacitors all around. Most notably the electrolytics. By the way .01pf would be an unlikely value since I don't think you can easily find one much lower than 1pf.
Thanks for everyone's replies. I will post a reply when I correct the fuse blowing problem. Then I will start replacing the electrolytics which are not easy to find in sizes (physical) similar to the originals. Thanks again.
Unless the capacitors show any signs of stress i.e. a pimple bulge and leaking gunge they're probably ok. Check out the power stages for shorts...namely the output transistors ( all transistor design) or maybe the power amp output module!! if this is at fault you may strugle to obtain a replacement. If you do manage to repair it after finding the fault within the output stage, make sure your speaker connections are good and not shorted!! Early amplifier designs often died as a result of shorting speaker leads.