The ones I used to see generally had the SSP45N20A (now obsolete). I generally used the IRF3415 as subs. In the amps that originally had IRF540s, I replaced with the same.
The 540N has caused a lot of problems in Rockford amps. If you have strange problems, try the non-N version.
The attached diagram is similar to the 2300.
The 540N has caused a lot of problems in Rockford amps. If you have strange problems, try the non-N version.
The attached diagram is similar to the 2300.
Okay....more tests. Rectifiers are out. All 6 PS FETs are in place.
Tried with 47ohm gate resistors - a little bit better but still the FETs are getting way too hot.
Left it like this for a little bit longer and one of the FETs popped - my power supply went into protect. No big deal as these FETs are relatively cheap.
I still think that even if I fit the board back into the case - that's not normal...2A amps of idle current with the rectifiers out...it should be like 5 times lower than this. All of this energy goes as heat through the FETs...but why ?!
I just don't feel confident to reasemble the amp like this, even if it produces output, but heats up like a barbeque on a hot sunday day in...florida...
PS: Lowering the value of the gate resistors makes it even worse...
Tried with 47ohm gate resistors - a little bit better but still the FETs are getting way too hot.
Left it like this for a little bit longer and one of the FETs popped - my power supply went into protect. No big deal as these FETs are relatively cheap.
I still think that even if I fit the board back into the case - that's not normal...2A amps of idle current with the rectifiers out...it should be like 5 times lower than this. All of this energy goes as heat through the FETs...but why ?!
I just don't feel confident to reasemble the amp like this, even if it produces output, but heats up like a barbeque on a hot sunday day in...florida...
PS: Lowering the value of the gate resistors makes it even worse...
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Does the amp have a protect mode for the power supply?
For the MTX amps where FET heating was a problem, the amp would only heat up a small amount (never uncomfortable to touch) if left idling (fully reassembled, FETs clamped to the heatsink). They were reliable.
Have you tried clamping them down to see how much the sink heats up?
For the MTX amps where FET heating was a problem, the amp would only heat up a small amount (never uncomfortable to touch) if left idling (fully reassembled, FETs clamped to the heatsink). They were reliable.
Have you tried clamping them down to see how much the sink heats up?
It does heat up a lot for like 20 seconds, but this is out of the case.
Haven't tried to clamp it to the sink so far...next step is to put it back into the case and run it assembled.
I meant my laboratory power supply went into protect not the amp... my bad I'll edit the post.
I will post an update shortly.
Haven't tried to clamp it to the sink so far...next step is to put it back into the case and run it assembled.
I meant my laboratory power supply went into protect not the amp... my bad I'll edit the post.
I will post an update shortly.
Sorry for the late response...Fitted brand new IRF540 (non N) version...changed all the broken glass diodes.
Back to the case and it works like a charm !
Great amplifier.
When bridged to 4 ohms (2ohm stereo) it get's quite fast warm. Not hot but warm. I bet if pushed hard it will get hot a lot.
Back to the case and it works like a charm !
Great amplifier.
When bridged to 4 ohms (2ohm stereo) it get's quite fast warm. Not hot but warm. I bet if pushed hard it will get hot a lot.
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