RF Power 1001bd Dead... but how??

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ok, I slapped a jumper in and it appears to power up! I also pulled the jumper back off and it is still able to power up... however, its been a long time since i've used this amp so I don't recall if the protect light use to come on for a second then go out. somewhere near the large transformer or perhaps the capacitors right by the battery terminals there is a high pitched sound like nails on a chalk board.... I didn't leave it powered up long enough to check the speaker outputs. I figured it would be best to check in with you to see how to proceed.
 
The protect LED will light up for a few seconds then it will go out.

Is pin 4 charging to over 4.5v after about 10 seconds (no jumper). If so, the cap may have been leaky and connecting the 5v to it rejuvenated the dielectric.

Leave the 15 amp fuse in the B+ line and power it up and down several times, leaving it playing for a while between cycles.
 
Sometimes loose windings can produce audible noise as the regulator in the amp modulates the pulse width to maintain the proper voltage. Sometimes moving the windings slightly will quiet them. There is a slight chance that it's something else but if it's not blowing the 15 amp fuse, it's not drawing excessive current.
 
After many more power ups and shutdowns the squeal is gone. when I was trying to locate it the sound was coming from the output side of the amp, thinking maybe the output coil possibly. I've found out however the gain pot is pretty shot so I'll be replacing that when I find something suitable.
Pin 4 charges up to 4.75 volts in approximately the same time its taking for the protect light to go out.
I bumped up the fuse size and played a bit of music through it at a moderate level and everything seems to be just how I remember with this amp.

When I go to reassemble does it matter the type of thermal grease I use. I only ask because I have a tube of arctic silver cpu grease laying around from previous computer work.
 
Ok, quick update... when playing music I've previously only let it play a few minutes between power downs. this morning I let it got about 20 minutes and out of nowhere the music disappeared and a horrible noise started coming from the speaker. I immedeately pulled the juice because it freaked me out. I plugged it back in with the probe on pin 4 and now its only charging to about 1.04 volts and starts slowly dropping off. When the voltage gets around .75 volts or so is when it starts making noise out of the attached speaker.

with the jumper between pins 4 and 18 all seems to be well.

If i remove the jumper it will start up and charge to 4.75 volts and maintain for about 1 minute now then it rapidly drops to just under a volt. After this is when it will only go up to just above a volt until its jump again with pin 18.
 
ok, I was looking though my collection of parts and the smallest uF cap I have on had is a 10uF 50volt cap. It would seem to be a bit overkill but I was wondering if perhaps it would work for testing purposes. Looking at the original one there is a 2.2 stamped on top and what looks to be a 5v right under that. I'm guessing the one in the amp is only a 2.2uF 5 volt cap.
 
ok, I put the 10uF cap in and it still jumps up to 4.76 volts about the same time that the protect light turns off after powering up. I have partially put the amp back together so the everything is mounted back to the heat sink. I've turned it on and played music through it a few times now for about 5 minutes between power offs and it seems to be holding charge. Guess I'll get one of those on order along with the gain pot. I requested a schematic via email from rockford, not sure if they will give it to me or not.

Do you happen to have one for this particular model?

I've noticed if I feed the amp input full range music like using my iPhone as an input it sounds a bit scratchy sounding like a static radio station, its not too noticeable especially with the woofer in the box, but I have the woofer in free air and its much more noticeable being close to it. If I load a track on the iPhone that has all the highs cut out it sounds just fine. Does this amp just have a not so great crossover or is there possibly something else going on?
 
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