The amp has audio when using ps. It starts at 13.78v then has only around 7.5 volts as somthing near caps and transformers clicks ever softly.
quietly.
When connected in vehicle i get the loud thumping noise of a bad ground. I sometimes get static. Sometimes nothing. At first red protect for a sec then green. When i increase input level its as its run out of power and protect comes on.
This is a ab amplifier and i maybe not doing something correctly. Im looking hard at the four big caps. (Pic)
Also im getting -17.40v on two (rectifing?)fets and 0 on the other two.(pic). Clueless
quietly.
When connected in vehicle i get the loud thumping noise of a bad ground. I sometimes get static. Sometimes nothing. At first red protect for a sec then green. When i increase input level its as its run out of power and protect comes on.
This is a ab amplifier and i maybe not doing something correctly. Im looking hard at the four big caps. (Pic)
Also im getting -17.40v on two (rectifing?)fets and 0 on the other two.(pic). Clueless
Attachments
Do the rectifiers have broken terminals?
Do you have output from the power transformer reaching the outer legs of the rectifiers?
Do you have output from the power transformer reaching the outer legs of the rectifiers?
Im getting between 5.5v- 6.7v from outer transformer legs to outer rectifier legs. All negative perry. I have 13.78v across power inputs.
No the legs look fine.13.8v on center supply fets.
No the legs look fine.13.8v on center supply fets.
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S494p
1. 16.7
2. 16.8
3. 3.75
4. .19
5. 2.31
6. 3.28
7. 0
8. 13.86
9. 2.2
10. 2.2
11. 13.86
12. 13.07
13. 4.85
14. 4.85
15. 4.90
16. .12
1. 16.7
2. 16.8
3. 3.75
4. .19
5. 2.31
6. 3.28
7. 0
8. 13.86
9. 2.2
10. 2.2
11. 13.86
12. 13.07
13. 4.85
14. 4.85
15. 4.90
16. .12
"Do the rectifiers have broken terminals?"
No. But if i push on one of them i get noise and positive voltage.
Its defected or broken inside the casing.
You da man! Again
No. But if i push on one of them i get noise and positive voltage.
Its defected or broken inside the casing.
You da man! Again
No sir. The #s are D25-04N and D25-04C. Would there be a more common part # that I could substitute ? When I twist the noise quits. What happened was when i pushed the diode against the heatsink the amp acted normal. With me touching it. Twisting the round chokes changes the noises also.
The N and Pos. Rectifiers are 400v peak reverse and 280v max rms voltage. Max Dc blocking of 400v and peak forward surge current of 150A.
I was able to find that info.
Thanks for the help
The N and Pos. Rectifiers are 400v peak reverse and 280v max rms voltage. Max Dc blocking of 400v and peak forward surge current of 150A.
I was able to find that info.
Thanks for the help
It appears that severl things affect the operation. Remove the rectifiers and confirm that they have an internal break (or not).
They all read about the same. 455-459Ω on diode on DMM. On the outer leg holes on pcb all read as connected to each other. All the outer legs short to each other ? The amp 13.98@ terminals . 14.10 @ center on supply fets. 3.00 on center rectifier holes. black probe on ground terminal red on rca output outer shield 2.90. Red probe on input rca outer shield .01
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On diode check, the reading isn't ohms, it's volts and has a decimal. Re-post with the correct information.
All outer legs are connected to one end of the secondary windings. They are connected by the secondary winding.
All outer legs are connected to one end of the secondary windings. They are connected by the secondary winding.
D2504C pos.rectifier =.457-.459vdc.and .455-.458vdc.
D2504N neg. Rectifier .460-.461 vdc and .458-.459vdc.
D2504N neg. Rectifier .460-.461 vdc and .458-.459vdc.
Did you find any intermittent connections when testing the rectifiers? It appears that you have an intermittent problem and we need to determine where it is.
Ive got the amp quiet as far as pops and other racket. Im not getting positive voltage on rectifiers. When I put red probe on center leg of pnp i get 0.0v and protect light comes on. When i remove probe , protect light goes off. When the amp is in protect at 6.5v I get both positive and negative voltages. -18.90
1
1
When it was in protect i was getting about 6.5v at power input terminal from my power supply. It would cut my almost 14. Volts down to that. Then my pos. and neg. readings were somewhere around -5v and +5. I have it installed in vehicle thinking my power supply wasnt strong enough. I have a heart beat thumping with the input sensitivity switch set to 100mv-2v. and not the 2v.-9v. setting. I believe i will try and order rectifiers. I checked all the solder joints and resoldered anything that looked suspicious.
Before it made loud popping noises. Now a heart beat. Lol. My wiring is overdone in vehicle.
Before it made loud popping noises. Now a heart beat. Lol. My wiring is overdone in vehicle.
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