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Velodyne sub woofer blowing fuse...HELP!

iceboxbass

Living the Dream!
Feb 22, 2010
14,884
10,852
Michigan
Hi!

I have a Velodyne CT-120 that I use in my home entertainment system. The issue that I'm having is that it keeps blowing its fuse on the circuit board, 2amp fuse. I've taken the circuit board out of the sub cab, looked around for anything obvious like swollen/cracked components, burnt or scorched spots, shorted wires/solder bleed over, cracked solder joints, NOTHING. But I did find some white powdery residue on one side of a black wire connected to rear circuit board that's in front of the transformer and there are a couple of condensers in that area on same board as well. Not really sure what the white powdery substance is, also there is some brownish substance in a couple of places on the rear board closes to transformer on a cap. I installed a brand new fuse last night and while I still had the circuit board/back panel removed away from the cab, I plugged in the power cord, turned power switch on and the fuse blew right away. If you have any insight that you could share I'd sure appreciate it so very much. Thank you!
 

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Shorted output section probably. Blown transistor. You won't be able to fix it without a schematic, and certain knowledge. Off to the tech!
Thank you David for your insight. I'm handy with electronics and soldering but I'm having trouble finding a schematic for this. I might just contact Velodyne to see if I can buy another power circuit for it. This one is outdated but perhaps one of the new power circuits will work with this sub. It's worth a try.
 
Thank you David for your insight. I'm handy with electronics and soldering but I'm having trouble finding a schematic for this. I might just contact Velodyne to see if I can buy another power circuit for it. This one is outdated but perhaps one of the new power circuits will work with this sub. It's worth a try.
Maybe, but I doubt it. Sorry to be a wet blanket but honestly, if you can't troubleshoot it at board level, it's probably not worth persuing. You'd be surprised how tough it can be. You gotta really know your $∆!t.
 
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Maybe, but I doubt it. Sorry to be a wet blanket but honestly, if you can't troubleshoot it at board level, it's probably not worth persuing. You'd be surprised how tough it can be. You gotta really know your $∆!t.
I took electronics in HS and then trained in electronics troubleshooting/repairing in the USAF 26 yrs, but I need schematics for this. I can test component by component but I'm really not wanting to take that kind of time (hours/days unless I get lucky) repairing this sub. Just hoping someone else ran into this same kind of thing with Velodyne subs. Might be time to upgrade to a 15"! Find a great Christmas sale! Or buy a floor demo model for less $$$. :)
 
I took electronics in HS and then trained in electronics troubleshooting/repairing in the USAF 26 yrs, but I need schematics for this. I can test component by component but I'm really not wanting to take that kind of time (hours/days unless I get lucky) repairing this sub. Just hoping someone else ran into this same kind of thing with Velodyne subs. Might be time to upgrade to a 15"! Find a great Christmas sale! Or buy a floor demo model for less $$$. :)
See my above post.
 
I took electronics in HS and then trained in electronics troubleshooting/repairing in the USAF 26 yrs, but I need schematics for this. I can test component by component but I'm really not wanting to take that kind of time (hours/days unless I get lucky) repairing this sub. Just hoping someone else ran into this same kind of thing with Velodyne subs. Might be time to upgrade to a 15"! Find a great Christmas sale! Or buy a floor demo model for less $$$. :)
OK, you have the knowledge and maybe the tools. I'd suggested posting on some techy HiFi site? Maybe try Velodyne themselves? You'd probably have better luck.
 
7You're welcome. I was an AV dork before I knew the difference between a guitar and a bass guitar, so I gotta rep for my Hi-Fi homies whenever I can.:roflmao:

Anyway, back to the board. Does any part of it smell weird? Any singe marks on the PCB? Those could be your first clue to finding the busted component. Failing that, you may want to check the power cord. If it has a short, then all bets are off.

Finally, a huge +1 to calling the company. I know emails are easier in every sense of the word, BUT THEY DON'T GET **** DONE LIKE A GOOD PHONE CALL! Take it from someone with horrible social anxiety and dreads talking on the phone; calls have their place, this is one. Velodyne's number is +1-408-465-2800. They're hours are 7:00AM to 4:30PM PST. Call them!
 
7You're welcome. I was an AV dork before I knew the difference between a guitar and a bass guitar, so I gotta rep for my Hi-Fi homies whenever I can.:roflmao:

Anyway, back to the board. Does any part of it smell weird? Any singe marks on the PCB? Those could be your first clue to finding the busted component. Failing that, you may want to check the power cord. If it has a short, then all bets are off.

Finally, a huge +1 to calling the company. I know emails are easier in every sense of the word, BUT THEY DON'T GET **** DONE LIKE A GOOD PHONE CALL! Take it from someone with horrible social anxiety and dreads talking on the phone; calls have their place, this is one. Velodyne's number is +1-408-465-2800. They're hours are 7:00AM to 4:30PM PST. Call them!
I didn't smell anything out of the ordinary but a short in the pwr cord is a great idea. Tomorrow I'll get my multimeter out and do a continuity test on it. Sometimes it's the most obvious that we don't see, even though I try to keep that foremost in my mind when troubleshooting. Thanks for the phone #, I've been on their page as well. Yeah I tend to tire going thru phone trees waiting and waiting and waiting...but sometimes it's the best avenue. Cheers!