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PCampenon
17-Dec-06, 18:58
I just finished my AMP32PS. At first, it did not work (no sound, no lighting of the LED). I checked all the connections, especially the soldering of the IC. As nothing seemed wrong, I powered it again , to measure the voltages here and there.... and everything looked OK on one channel, with really good sound, and a faint sound on the oter channel. The LED did not work. However 5V on the gate of the 2N 7000. and 14V on its power rail.
Switch off again, and checking of all the signal path along the related channel: I tried to improve a soldering which looked bad.
And now, switch ON and... :( no sound on any channel, whereas power rail is OK, DC offset on each output ~ 7V, DC offset at input ~ 2 V, J2-2 grounded, ...

It looks like a bad soldering somewhere which conducts or not ...
Does somebody have an idea for investigation, other than visual inspection which I did without finding anything ?

Thanks to all... I'm impatient to appreciate the AMP32PS, as much as my AMP 6 which is really estonishing!:D

V-bro
19-Dec-06, 23:48
AMP32 is really amazing, be patient...I've built eight of'em so far and must agree it can be hard to get it working...but finally I got'em all together well! :)

Don't forget to clean away the solder flux!

X-max. can be several meters on any driver, too bad it can only be done once...