orion xtr 1000

[timwebb]

im working on one of these and. im getting no output from the amp. i found im getting 8.59 which suppose to be negative. on the ground pin on all the opamps.

 

[brandes.cm]

So you are getting +8.59Vdc on the negative supply pin of the op-amps? Are any op-amps getting warmer than the rest?

 

[timwebb]

a few are warm. they are all surface mount.

 

[brandes.cm]

Lift the negative supply pin on those one at a time. See if your voltage returns to normal.

 

[ultra]

excellent

Lift the negative supply pin on those one at a time. See if your voltage returns to normal.

Very nice, i use the same technique.

 

[Perry Babin]

Either the negative regulator has failed or something connecting the negative regulator to the op-amps has opened. There may be a shorted op-amp as well so when you repair the regulator, be careful when powering it up.

Post a photo of the inside the amp.

 

[timwebb]

i lifted the pins now i get 25v at the ground for the opamps

 

[Perry Babin]

Do you have negative input and output voltage on IC722 and IC732?

Isn't this an XTR 10001?

 

[timwebb]

yeah it is..had to take the tape off.

 

[timwebb]

Do you have negative input and output voltage on IC722 and IC732?

both ic's have negitive voltages on it.

 

[Perry Babin]

There is a 10 ohm resistor connected to each output of ICs 741, 742, 751 and 752. Check those resistors. If any one has failed replace all with larger (1206) 10 ohm resistors.