Q1009 collector : held the probe on it longer voltage jump around the same as Q1016's base does
Should i try replacing Q1016 and then test voltages?
Should i try replacing Q1016 and then test voltages?
OK replaced Q1009 and Q1016
Q1009
Collector:14.39
Base:13.70
Emitter:14.41
Q1016
Collector:44.03
Base:14.39
Emitter:13.82
If i turn the Bias pot up the voltage on thoose 2 transistors starts jumping all over the place ...
If i turn the bias pots up the current draw will not increase..
The Pots are fully counter clockwise right now
Q1009
Collector:14.39
Base:13.70
Emitter:14.41
Q1016
Collector:44.03
Base:14.39
Emitter:13.82
If i turn the Bias pot up the voltage on thoose 2 transistors starts jumping all over the place ...
If i turn the bias pots up the current draw will not increase..
The Pots are fully counter clockwise right now
What board # is in this amp? The diagram that I have indicates that it should have 28v of rail, not 40+.
I think the voltage on the diagram is wrong.
When you adjust the bias and the voltage fluctuates on those two transistors, is there any significant voltage driven to the speaker terminals?
When you adjust the bias and the voltage fluctuates on those two transistors, is there any significant voltage driven to the speaker terminals?
Ok i got + - 13 volts on the op-amps..
The gain was turned all the way up thats why i had a square wave on pin 7
Still have very distorted output on both channel outputs..
The gain was turned all the way up thats why i had a square wave on pin 7
Still have very distorted output on both channel outputs..
Are you 100% sure that every component that you replaced was with the correct type/value?
Are you 100% sure that the connections between the bias transistors and the main board are intact?
Are you 100% sure that the connections between the bias transistors and the main board are intact?
Yes 100% sure every part that was replaced is the correct one And the correct value..
Yes 100% sure that the bias transistors are making contact with the main board..
Should i replace the Bias transistors to see if they are defective ?
Yes 100% sure that the bias transistors are making contact with the main board..
Should i replace the Bias transistors to see if they are defective ?
Last edited:
Check the pots to confirm that they both have the marked resistance across their terminals and the wiper swings (measure resistance at various points in the rotation) from one outer terminal to the other.
Both Pots are marked 202 So guessing they are 2K pots ??
Left channel bias pot fully counter clockwise i get :0.647K ohms
With the bias pot fully clockwise i get: 8.3 ohms
Right channel fully counter clockwise i get:0.667K ohms
fully clockwise i get:8.5 ohms
Turning them at various points i get different reading so im guessing they are working like they should
Left channel bias pot fully counter clockwise i get :0.647K ohms
With the bias pot fully clockwise i get: 8.3 ohms
Right channel fully counter clockwise i get:0.667K ohms
fully clockwise i get:8.5 ohms
Turning them at various points i get different reading so im guessing they are working like they should
Power supply Transistors was what failed in the amp along with the gate resistors and drivers for the power supply and the Lm 317T also failed...
Outputs were never touched..
Outputs were never touched..
If you place the black probe on the source of Q1024 and the red probe on the gate of Q1024 and turn the bias up, what is the highest voltage that you read?
- Status
- Not open for further replies.