Clarion DPX11500 #2 Repair

[Zeptoplix]

Sorry, I was looking at the amp last night before you posted Matthew, and haven't found anything else.

I was checking voltages along the path from the speaker out back and couldn't find a source for the 8.91V, but now I have +48 again on the output. I think this amp may just be the type to put in the closet and forget about .

 

[Zeptoplix]

Was hoping i'd get a pinch hitter on this, but 10 pages and 1,000+ views in I feel like we should push forward some how.

Please post the following voltages, powered up, unloaded, no signal, and once the dc offset has settled to that lowest reading of 8-9v.

U2:

Pin 1
Pin 7

Banded end of D18
Non-Banded end of D19

The schematic doesn't show me proximity, but since you mention it you can try decoupling those parts from the drive by lifting one leg of c13 to see if it rectify's your issue, but ONLY once you've got me those voltages. If you lift it, take a measurment on either side of r37 then for me.

Hi,

I have not given up quite yet.

I have the following measurements from U2

Pin1) 32.68V
Pin 7) 32.68V

Banded end of D18 is 4.5mVDC
Non banded end of D19 is 3.3mVDC

I removed C13 and tested R37 and got 24.7mv, same and it settled on the same voltage on speaker out (in the 8.9-9.1VDC range.

 

[MatthewS]

Post full voltage readings at u2 pins, all of them.

 

[Zeptoplix]

I haven't tested this amp in a while, but I did start messing around with it tonight.

The voltage will not go lower than +44VDC. Checking the block diagram I see that VAMPL + and - voltage is +45 and -45 VDC.

If I am reading correctly, it looks like this is related to U13. However, when I test Pin 13 and Pin 5 I do not get those voltages.

U2
1 +9.18VDC
2 + 9.19VDC
3 +9.12VDC
4-16.3VDC
5 .7mVDC
6 .5mVDC
7 -9.17VDC
8 +16.39VDC

I also get +44 on all pins of all outputs.

edit:

Now that I check again, my speaker output is down to +10VDC or so on speaker out.

In this state I get identical voltages on all pins except 4 and 8
4 -14.15
8 +13.95

Obviously there is an intermittent issue working here as well.

When tapping C46 I can get the voltage to go back to +44 or I can get it to drop back down. This is approximately dead centre on the board.