I just finished (at least that's what I thought I did..) an lm3886 BrianGT kit, but when I powered up I measured some strange values.
First of all, the power supply board makes 28VDC from 22VAC. Not exactly the 1.4 factor I was expecting.
Next, when I measured the DC offset, it was huge: about 1.6V on one channel and 1.7V on the other and the chips get very hot after running for some minutes without any load.
Any advice?
First of all, the power supply board makes 28VDC from 22VAC. Not exactly the 1.4 factor I was expecting.
Next, when I measured the DC offset, it was huge: about 1.6V on one channel and 1.7V on the other and the chips get very hot after running for some minutes without any load.
Any advice?
something is wring with your connections , dont power it up again u will burn the chip , show some pics if u can
Sorry, already took it apart. I've had it with those really stiff solid core silverized-copper (?) wires. Had to solder the - hard to reach - connections with the pcb's mounted in the case, that was just asking for bad connections.. Now I'll give it a go with some multi stranded wire and report back when I'm finished.
Done! Now with DC offset 0.5 and 0.3 mV (not accounting for deviation of my 15 euro multimeter 😉 ). There was probably some shortage going on 
- Status
- Not open for further replies.