I am working on this power acoustik amplifier and am in need of some parts help. I can not locate the 680uF 120v 18x30mm hole through Capacitors. Labeled LM GR 105 680uF 120v
Please any help!!!!!
Also the rail capacitors are 3300UF 100WV? 25x30 snap in capacitors. I need these as well. i purchased some already i would haft to drill out the board to make them work on one of the holes.
Please any help!!!!!
Also the rail capacitors are 3300UF 100WV? 25x30 snap in capacitors. I need these as well. i purchased some already i would haft to drill out the board to make them work on one of the holes.
In photos, I see 2200@100 for the rail caps.
What's the problem with the 680s? Those are parallel with the main rail caps, aren't they?
What's the problem with the 680s? Those are parallel with the main rail caps, aren't they?
NO shorted components, but someone has rebuilt this ampliifer, my quess is the capacitors were bad then even, Just were not checked when the outptuts and power supply was refurbished. The non blown caps test low like 500uF for the 2200 so they are way bad all of them. 680 vented all the way in half. I think i found some capacitors for the 2200 they are a bit taller at 25x40mm but shouold do fine. Can i use 1000uf for the 680uF perry, and the amp will function just fine?
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If someone has worked on the amp before, there could be damaged vias. It's critical that all vias be checked and if damaged, jumpers installed to re-establish the connections.
The 1000uF should be OK if the caps are parallel to the main rail caps.
Was the 3300uF in the first post a typo or what you found in the amp?
Were ALL of the larger rail caps damaged?
The 1000uF should be OK if the caps are parallel to the main rail caps.
Was the 3300uF in the first post a typo or what you found in the amp?
Were ALL of the larger rail caps damaged?
Yes a typo perry. My mistake there 2200uF 100v 25*30mm and 680uF 120v 18*30mm, four out of 8 and two of the 680uf.
Whomever did the repair was experienced beacuse the work was good no damage, just over looked the already damaged caps.
Whomever did the repair was experienced beacuse the work was good no damage, just over looked the already damaged caps.
Someone has replaced the reverse polarity diode so I believe that's how the caps became damaged then when they replaced the diode it wasn't long before the explosion happened. I'll need to check them all.
Few other things I noted we're one side of output transistors production codes do not match the other as well as in the power supply. This all probably happened originally.
Few other things I noted we're one side of output transistors production codes do not match the other as well as in the power supply. This all probably happened originally.
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The RP diode has no connection with/to the rest of the problems.
If all of the failed caps were on one rail, it's likely that you have a problem with either the high or low side FET drive. This is common in the type-2 clones where Q124/125 fail. I've never seen it in a 21844 amp but it may be possible.
If all of the failed caps were on one rail, it's likely that you have a problem with either the high or low side FET drive. This is common in the type-2 clones where Q124/125 fail. I've never seen it in a 21844 amp but it may be possible.
Without the caps in curcuit and I have the rectifiers removed from the curcuit. Soni should remove the output transistors and look at the dirive signals?
I think I would reinstall the rectifiers, install a single good 2200uf cap on each rail (use short length of wires if you're concerned about damaging the vias) and drive the amp into a light load to see if either rail is changing significantly when the amp is driven.
It would be best to have all of the FETs clamped down for this to prevent damaging any of the FETs from overheating.
It would be best to have all of the FETs clamped down for this to prevent damaging any of the FETs from overheating.
On a input signal 1-4v All the lowside and highside drive looks identical. Both i/c have been changed and all the 104 disk capacitors with them all the voltage regulators and the half of the outputs and the power supply. All the volatges are correct. I remember them from a hifonics amp you helped me repair. I'm thinking someone just missed the damaged caps when it failed previously,repaired the obvious parts and sent it out. Most of them vented or leaked from the top and the others just tested very low 1200uF or lower and were leaking.
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