Soundstream XXX6500

[mike49504]

PIN9:-120.0
PIN14:-120.0


RA18 is a 330 ohm and it measures 328.7 ohms

RA19 is a 200 ohm and measures 199.1

 

[Perry Babin]

It appears that there is a bad connection between the cathode of DP11 and R18.

 

[mike49504]

I reflowed the solder on all parts from DP11 to RA18 and have -120.1 volts still on pins 9 and 14.

I have no voltages on QA1 and QA2 still.

 

[Perry Babin]

QA1 is fed via DA1. Is it open?

 

[mike49504]

No I checked it out of the board and it measures 0.487 and the other direction 0L

 

[Perry Babin]

There's an open trace between the cathode of DP11 and that diode. The trace may be under some other components.

Run a 'fused' jumper (2 amp max) between the cathode of DP11 and the anode of DA1. Does the fuse blow?

If not, does the amp produce audio?

 

[mike49504]

QA1 on the cathode side i get 0.3 volts on the other side i get -92.9 volts

And voltage directly across it :93.2

 

[mike49504]

Ill have to go get a fuse in the morning to try it.

 

[mike49504]

Ok i did find a fuse. Tryed that and still no output.

With that jumper hooked up i still get no voltages on QA1 and QA2

the voltage is like .03 volts

 

[Perry Babin]

Look at the attached images. You can see how DP11 connects to the points I mentioned. +24VEE isn't now connected as shown. You have to determine why. The jumper should have restored the connection.

 

[mike49504]

C10 C11 are inductors They both appear to be defective. They connect to 1 side of R18

 

[Perry Babin]

C would indicate that it's a capacitor.

 

[mike49504]

Thats right. They have a green body with brown,black,yellow stripes.

1 measure .03 and the other 9.17 k out of circuit.

 

[Perry Babin]

They should both read as open circuits (OL). The 0.03 reading doesn't seem right unless it's 0.03M.

 

[mike49504]

Yeah they are both defective. I have to go get some parts in the morning and replace both of thoose.

 

[Perry Babin]

What was the actual resistance of the one that read 0.03?

 

[mike49504]

I dont know why the readings were like that. I measured it out of circuit and it just flashed numbers and went back to OL

 

[mike49504]

I dont get this .

DA1

On the anode side i have -93.4 volts the Anode side connects to DP11's cathode side.

On the Cathode side of DA1 i get no voltage.

 

[mike49504]

Is there any good cross's for the MJE172 and MJE182.

I found the 172 is defective That might be why its shutting down DA1

 

[Perry Babin]

Arrow has them.

The voltage on the anode must be higher than the voltage on the cathode for current to pass through it. Here, you'd need the voltage on the anode to be higher than 0.6v. It's currently 94v too low. This isn't a problem. It appears that you've restored the voltage to this part of the circuit. What is the DC voltage on pins 8, 9 and 14 of the driver board?