I recently purchased a Fender PA150. It gets power and goes straight to protect. I have already taken the PA apart very carefully and labeled every plug. I am troubleshooting and have gotten to a point at which I need a little direction.
1.Pulling the center power line to the Amplifier board remedies the protect light and it returns to the normal green power light.
2. Readings from the Power cable are as follows.
1.Pulling the center power line to the Amplifier board remedies the protect light and it returns to the normal green power light.
2. Readings from the Power cable are as follows.
A. Red --> Black1 = 52.2v DC
A. Red --> Black2 = 52.2v DC
A. Blue --> Black1 = -52.1v DV
A. Blue --> Black2 = -52.1v DV
A. Black1--> Black2 = nothing.
I thought these all looked fine so that leave s the amplifier board.....
What Do I test next?- Where is it located and what does it look like" and finally how do I test it? - as for testing gear i have a new oscilloscope, multi meter and other basic tools. Another post said to start testing each (something) for resistanct but i was unsure of what i was to be testing and how.
Brand new here to please let me know if im doing anything wrong.
I thought these all looked fine so that leave s the amplifier board.....
What Do I test next?- Where is it located and what does it look like" and finally how do I test it? - as for testing gear i have a new oscilloscope, multi meter and other basic tools. Another post said to start testing each (something) for resistanct but i was unsure of what i was to be testing and how.
Brand new here to please let me know if im doing anything wrong.
If it is brand new, it should be on warranty. You shouldn't mess with it.
Rail Voltages seem to be OK.
Connect the connector.
Check if You have DC on the outputs, but measure before the protection relay (not seen on the photo)
If there is DC, some drivers are kaputt.
Does this think have jack speaker outputs ?
Check for shorts on them or on the cables.
Rail Voltages seem to be OK.
Connect the connector.
Check if You have DC on the outputs, but measure before the protection relay (not seen on the photo)
If there is DC, some drivers are kaputt.
Does this think have jack speaker outputs ?
Check for shorts on them or on the cables.
His Passport 150 (no PRO) is an old product, no warranty. (Even the PRO successor is discontinued.)
It would really help to have a schematic. It is not on Fender's site, and not found in a hasty web search. It really is not meant to be serviced in the field.
It appears to be a basic linear power amplifier. Analogy from experience can be a guide. I used to do this for pay but am long out of practice.
It would really help to know what "protect" means. There are several things that can go "wrong" in a power amp. In ignorance I would be looking at the DC volts at the speaker jack (should be under 0.1V). A "popular" failure is one side of the push-pull goes short and pulls the speaker to 50V(!) DC. However if protect is shutting the amp down, you may need to know how that works to defeat it.
If you just bought it, talk to the seller.
It would really help to have a schematic. It is not on Fender's site, and not found in a hasty web search. It really is not meant to be serviced in the field.
It appears to be a basic linear power amplifier. Analogy from experience can be a guide. I used to do this for pay but am long out of practice.
It would really help to know what "protect" means. There are several things that can go "wrong" in a power amp. In ignorance I would be looking at the DC volts at the speaker jack (should be under 0.1V). A "popular" failure is one side of the push-pull goes short and pulls the speaker to 50V(!) DC. However if protect is shutting the amp down, you may need to know how that works to defeat it.
If you just bought it, talk to the seller.
Protect lite comes on to indicate the SMPS has shut itself down.
Most common reason for that is short in the PA. Hence, check the output transistors for shorted condition.
Fender only has a small selection of schematics online, but if you CALL them, they will generally provide any schematic you ask for. Note they will send schematics for Passport models, including the power amp, but they don't send out the SMPS schematic as they consider it a "part".
Most common reason for that is short in the PA. Hence, check the output transistors for shorted condition.
Fender only has a small selection of schematics online, but if you CALL them, they will generally provide any schematic you ask for. Note they will send schematics for Passport models, including the power amp, but they don't send out the SMPS schematic as they consider it a "part".
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