Perry heres the B52
1. 11.92
2. .000
3. 5.36
4. .216 nice triangle wave
5. .002
6. -12.39
7. .000
8. 2.750
9. -1.765 no square wave
10. -1.887
11. -1.492 no square wave
12. -.02
13. 2.759
14. 2.759
It should be producing a square wave on 9 and 11 everything looks good your repair disk shows me everything. Is it a bad IC ? The B52 on the " type 1 class d " didnt throw me off I knew that the lable was upside down good one LOL you can bearly see the lm361 , but yes it can happen installing a ic backwards not good .
1. 11.92
2. .000
3. 5.36
4. .216 nice triangle wave
5. .002
6. -12.39
7. .000
8. 2.750
9. -1.765 no square wave
10. -1.887
11. -1.492 no square wave
12. -.02
13. 2.759
14. 2.759
It should be producing a square wave on 9 and 11 everything looks good your repair disk shows me everything. Is it a bad IC ? The B52 on the " type 1 class d " didnt throw me off I knew that the lable was upside down good one LOL you can bearly see the lm361 , but yes it can happen installing a ic backwards not good .
Iam sorry . Is this the B52 in stock at radioshack or just order it from digikey? And would this be causing the -63 volts on the speaker terminals ?
Perry changed out the LM361 aka B52 from a Memphis 1000 . Now the outputs 9 and 11 are at different voltages 9 is -1.2 volts and 11 is +1.2 volts . The speaker terminals are now -31 volts . I was probing next to the B52 on one of the Integrator and my probe sliped on pin 5 and 6 smoke .... Installed other TL072 and now put a ribbon cable to check this board better. Now on this TL072 no wave form on pin 1. and no 12 volts on pin 5. ? I was tracking back from pin 5. to see if I burned out a resistor but I had to get ready for work.
Perry the B52 pins 9 -1.2v and 11 +1.2v had no square wave form , just a flate line voltage . Thats not right , or is it ?
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Ok will check out why the integrator isnt sending the triangle waveform . On the other integrator pin 1. is producing a triangle waveform .
There should be only one integrator. Its output goes to the LM361. Is the triangle waveform present on pin 4 of the LM361?
Perry the triangel waveform is real ugly it lands up + 1.2 volts and looks like a flat line but it has alil triangel waveform .
If you still have -63v on the outputs, the feedback circuit is trying to compensate so it's pushing the other input of the comparator up which is dragging the integrator signal up. Do you have any components out of the circuit as of now?
Do you still have ±1.2v on pins 9 and 11 of the LM361?
Do you still have ±1.2v on pins 9 and 11 of the LM361?
Perry yes I still have -63 volts on outputs , and one 9450 is still getting hot , other two stay cool . Everything looks good on the F16 and B52 board but on the F16 pin 9 10 11 should have 2.56 mhz on them the only one that does is pin 9 is that right ?
Check the gate resistor for that 9640 (or is it a 9540?). If the gate resistor is within tolerance, remove the FET to see if it's leaking.
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