Anyone have a schematic for this amp? I need help identifying components:
C66
C109
R134
C108
And also why these failed. Looks like someone replaced C66 and C109 with 10uf470v caps, and R134 is measuring 58 ohms. C108 isn't measuring anything.
Thank you
C66
C109
R134
C108
And also why these failed. Looks like someone replaced C66 and C109 with 10uf470v caps, and R134 is measuring 58 ohms. C108 isn't measuring anything.
Thank you
I found this thread which had some clear photos.
https://www.diyaudio.com/community/threads/kicker-zx1500-1.271621/
I installed 10uf200v NP caps in C66 & C109. Installed a 47 ohm resistor in R134, and a C108 cap from a parts board.
When powering, the amp draws excessive current and R134 smokes up.
If I remove the driver board in the center, the amp powers and idles at 2A draw with R134 staying at ambient temperature.
Im not 100% sure how to continue troubleshooting, but would the problem possibly the LM361 at U202 on the driver board?
https://www.diyaudio.com/community/threads/kicker-zx1500-1.271621/
I installed 10uf200v NP caps in C66 & C109. Installed a 47 ohm resistor in R134, and a C108 cap from a parts board.
When powering, the amp draws excessive current and R134 smokes up.
If I remove the driver board in the center, the amp powers and idles at 2A draw with R134 staying at ambient temperature.
Im not 100% sure how to continue troubleshooting, but would the problem possibly the LM361 at U202 on the driver board?
I removed the LM361 and the amp powers with the driver card installed. I'm observing good square wave on pin 5 of the MC14060B.
I'm thinking I need to order a new LM361.
I'm thinking I need to order a new LM361.
If you have the tutorial, the voltages and waveforms for the LM361 are shown on the type 1 page. Does your board match those?
I found a working parts amp that had a good LM361. Swapped in, the amp still roasts R134 and draws excessive current.
Next I'll remove the output FETs so hopefully I can test further items. I think most of the Type 1 pages are matching which I've been referring to. I'll have more time another time to troubleshoot further.
Next I'll remove the output FETs so hopefully I can test further items. I think most of the Type 1 pages are matching which I've been referring to. I'll have more time another time to troubleshoot further.
Output FETs removed.
LM361
1. 15.2
2. 0
3. 7.5 --> Shouldn't this be zero?
4. 3.2v triangular wave
5. 0
6. -15.6
7. 0
8. 4.6
9. 0.19
10. 0.011
11. 4.95vDC --> No waveform
12. 0.011
13. 4.65
14. 4.99
Mostly, these are matching the Class D type 1 page but not sure about some of those readings.
LM361
1. 15.2
2. 0
3. 7.5 --> Shouldn't this be zero?
4. 3.2v triangular wave
5. 0
6. -15.6
7. 0
8. 4.6
9. 0.19
10. 0.011
11. 4.95vDC --> No waveform
12. 0.011
13. 4.65
14. 4.99
Mostly, these are matching the Class D type 1 page but not sure about some of those readings.
There is break in the feedback loop due to the missing outputs.
There are multiple ways to make the DC go to 0v. If you connect pin 3 to a local ground (easy to find on one of the electrolytic caps or the ground terminal of the driver board.
There are multiple ways to make the DC go to 0v. If you connect pin 3 to a local ground (easy to find on one of the electrolytic caps or the ground terminal of the driver board.
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If a close magnet isn't causing the trace to be angled, use the trace rotator to straighten it.
What if you remove that jumper and bridge pins 6 and 7 of U200?
I don't have the diagram for this board so hopefully PapaZBill will help.
What if you remove that jumper and bridge pins 6 and 7 of U200?
I don't have the diagram for this board so hopefully PapaZBill will help.
Trace fixed.
Jumped 6&7 of U200 and removed the U202 pin3 ground. Signal is identical on pin 11 as post 9.
Volts and signals on output fet pads look OK to me:
Low output fets:
G: -131vDC and a clean +-10v square wave
D: 0
S: -135
High output fets:
G: 4.5vDC and a clean +-10v square wave
D: 136
S: 0
Jumped 6&7 of U200 and removed the U202 pin3 ground. Signal is identical on pin 11 as post 9.
Volts and signals on output fet pads look OK to me:
Low output fets:
G: -131vDC and a clean +-10v square wave
D: 0
S: -135
High output fets:
G: 4.5vDC and a clean +-10v square wave
D: 136
S: 0
I've tried that before but not honestly the greatest result but I can try again.
Which two points to probe?
Which two points to probe?
This is very important to learn. If it takes you a full day to get it right, take that day.
I want you to re-check the waveforms on the FETs placing ch2 probe on the source and the ch1 probe on the gate. 5v/div and 1us (or whatever gives about 3 full cycles on the display.
Do you have a meter that measures frequency?
I want you to re-check the waveforms on the FETs placing ch2 probe on the source and the ch1 probe on the gate. 5v/div and 1us (or whatever gives about 3 full cycles on the display.
Do you have a meter that measures frequency?
I didn't catch it earlier but the frequency looks too high. Measure the drive frequency at the outputs.