RockFord Fosgate P300-1

[Theripper973]

Hello Badcaps.com community. im new here but in need of some help/advice. I have a rockford P300-1 amp that will not work right. whenever i power it up, it powers up just fine. just when i plug in any subwoofer it starts flashing protect on and off rapidly. i know the subs aren't the problem because they work fine on my other amplifiers and the wiring is correct because both my amps work fine on the same wiring. The only thing iv seem inside the amp that might be bad is the 2 main capacitors. i can push on the top of them and almost feels like there's a small amount of air trapped in them. the caps in question are lelon 3300uf 50V caps. Any help is greatly appreciated!

[kc8adu]

Re: RockFord Fosgate P300-1

check the transistors with the red and blue ink for shorts/leakage.
if you can push down the plastic on the caps they are ok.

[Theripper973]

Re: RockFord Fosgate P300-1

What would leakage look like? Does it sort of look oily?

[Theripper973]

Re: RockFord Fosgate P300-1

i pulled off the little cover for the red and blue ink transistor and there seems to be alot of an oily substance between the little metal piece and the transistor. so what does this exactly mean?

[tron]

Re: RockFord Fosgate P300-1

it helps to transfer the heat(thermal compound)

better take the
amp to someone,
who deals
with those
issues daily
(amp repair guy)

[kc8adu]

Re: RockFord Fosgate P300-1

thermal compound can br oily.
i meant electrically leaky.
look for dc on the speaker leads too.
those amps are really easy to fix.
i just got 4 or 5 in a deal.make sure you dont get china counterfeit transistors or it will just blow up again!

[Theripper973]

Re: RockFord Fosgate P300-1

I guess for now im going to replace all the larger transistors. Dont want to fix it again down the road. Where could i buy good replacements?

[Theripper973]

Re: RockFord Fosgate P300-1

So im having trouble finding replacements on the exact transistors i need. so here are the numbers im reading and pulling off of them.

F B J25
FQA
36P15

This is how the numbers and letters look on the transistor itself and there are a total of 4 of these.

F 1J24AV
75344G

There are only 2 of these.

IF anyone who could point me in the right direction that would be great. im not sure which numbers i need to be searching for.

[kc8adu]

Re: RockFord Fosgate P300-1

[Theripper973]

Re: RockFord Fosgate P300-1

So what place should i order what i need from? all these places look kinda spendy but im thinking mouser is probably going to be the best? unless im wrong?

[kc8adu]

Re: RockFord Fosgate P300-1

mouser or digikey.avoid ebay.
lots of fakes/remarks.

[Theripper973]

Re: RockFord Fosgate P300-1

So i got all the parts needed ordered from mouser finally. I know that they will need some new thermal paste on the backside though. can i just use normal computer thermal paste? i have some cooler master stuff laying around but just thought id ask if this will work just fine?