Confirm that the rail is ~74Vdc and that the drive at both output inductors (IRS20957 side) is 1/2 rail. Post screenshots for both Test Points. Also, Measure Vdc around both IC14 and IC15 and post.
Scope Pins 3 of IC14 & IC15 with and w/o signal and post screenshots.
I realize this may be redundant, but I'm not getting a clear picture of the problem.
If the drive is good there may be an issue with the preamp.
Scope Pins 3 of IC14 & IC15 with and w/o signal and post screenshots.
I realize this may be redundant, but I'm not getting a clear picture of the problem.
If the drive is good there may be an issue with the preamp.
74.0vdc of rail.
36.80vdc at ic14 side.
14.43vdc at ic15 side.
changed ic15 same voltage is present after
36.80vdc at ic14 side.
14.43vdc at ic15 side.
changed ic15 same voltage is present after
Voltage of I/C's
ic14
1.) 10.35
2) 10.22
3) 4.289
4.) 0.00
5.) .001
6.) 5.232
7.) .789
8.) 11.99
9.) .001
10.) 6.201
11.) 12.29
12.) .002
13.) 36.90
14) 41.97
15) 48.56
16.) 38.31
ic14
1.) 10.35
2) 10.22
3) 4.289
4.) 0.00
5.) .001
6.) 5.232
7.) .789
8.) 11.99
9.) .001
10.) 6.201
11.) 12.29
12.) .002
13.) 36.90
14) 41.97
15) 48.56
16.) 38.31
voltage ic15
1.) 10.33
2.) 10.21
3) 8.95
4) 0.00
5.) 0.00
6.) 5.215
7.) .787
8.) 12.05
9.) 0.00
10.) 0.00
11.) 12.34
12.) 0.00
13.) 15.00
14.) 14.97
15.) 15.03
16.) 14.99
1.) 10.33
2.) 10.21
3) 8.95
4) 0.00
5.) 0.00
6.) 5.215
7.) .787
8.) 12.05
9.) 0.00
10.) 0.00
11.) 12.34
12.) 0.00
13.) 15.00
14.) 14.97
15.) 15.03
16.) 14.99
c327 is short out of circuit. This maybe the problem. value of the capacitor? 22-25uF 100v?
This was the fix. back up and working perfectly. Every amplifier i work on with you i learn something. Its truly appreciated.
This was the fix. back up and working perfectly. Every amplifier i work on with you i learn something. Its truly appreciated.
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I'm happy to help. I get great satisfaction when I hear you or others are able to repair an amp,even though the back and forth can be a bit frustrating at times. I work with engineering students who intern for Kicker as part of my job, and see them take what they learned and become successful Engineers. My credo is good Engineers must be good Technicians first!!