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SVT-7 Pro Repair Question

B

bcatchings

May 2, 2014
5
5
44
#1
Any of you guys have a schematic for an SVT-7 Pro? I'm trying to help out a buddy of mine whose gigging amp is dead. Found two obviously burned pieces on the main board and need to know a couple things before I can replace them. D3 is burned and the ICE2A165 power chip right next to it is also burned. Just need to know what kinda diode D3 is and if any of you know of a pin for pin replacement for the ICE2A165 that's a bit more heat tolerant. It appears you can still find them NOS but if there's a better part out there I'd like to switch to that. Any thoughts or help would be appreciated.

Thanks and all the best,
Ben
 
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#2
From what I've heard from an Australian tech you need to upgrade the ICE2A165 to a ICE2A265 (2 amp instead of 1 amp). I dunno know what the diodes are as I'm waiting for some friends to come thru on the service manuals on the 7 Pro.....

The article you need to read is Ampeg SVT 7 Pro - Reliability......
 
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#6
Ampeg's usually decent about releasing schematics if you promise not to post them online. They might "qualify" you a tad just to make sure you don't screw yourself up, but it's not like they have rigorous standards. Generally, if you know which end of the soldering iron is which and are willing to sacrifice your warranty if you have one, you're qualified.
 
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#7
JimmyM said:
Ampeg's usually decent about releasing schematics if you promise not to post them online. They might "qualify" you a tad just to make sure you don't screw yourself up, but it's not like they have rigorous standards.
Click to expand...
I would be grateful for a copy of the schematic "just is case" although it has always worked flawlessly.
My rep, Pro Tec in MD said that they could loose their authorized status if they made me a copy.
Jimmy if you can get a copy I would appreciate it.
 
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#8
Wait are you guys saying I can just call and talk to someone? Honestly if they could just tell me exactly what D3 is I'd be fine with that too. I tried the practical application sections on the ICE datasheet but the diodes shown in the schematics aren't labeled or even hinted at and that's understandable as I'm sure that's decided by the power specs for the circuit.
 
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#10
Actually yeah... it's got an Infineon ICE2A165 Offline SMPS Current Mode Controller in it. It's just south of that burned out D3.
 

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#13
I tried swapping out that ICE chip a couple years ago with the larger one only to find it heat up and shut down also. Quick fix was to place one of those copper heatsinks on it, the kind you use on memory chips with the sticky stuff on it. The chip still runs rather warm but does not go into shutdown mode. The tube filament is what seems to put the heavy load on the chip so the next SVT I get in for repair, think I'll add a 12v transformer just for the tube filament. should make the amp stable again.
 
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#14
mnow said:
I tried swapping out that ICE chip a couple years ago with the larger one only to find it heat up and shut down also. Quick fix was to place one of those copper heatsinks on it, the kind you use on memory chips with the sticky stuff on it. The chip still runs rather warm but does not go into shutdown mode. The tube filament is what seems to put the heavy load on the chip so the next SVT I get in for repair, think I'll add a 12v transformer just for the tube filament. should make the amp stable again.
Click to expand...

have yoy fixed the problem with svt-7??
 
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#15
Jim C said:
I would be grateful for a copy of the schematic "just is case" although it has always worked flawlessly.
My rep, Pro Tec in MD said that they could loose their authorized status if they made me a copy.
Jimmy if you can get a copy I would appreciate it.
Click to expand...

It is true that your service rep can not distribute schematics.

If you contact Loud and request a copy of the SVT-7Pro schematic, they will send you a set. You will need to supply your serial number and agree to their terms and conditions. Send your request to [email protected]
 
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#18
i think with all these numbers of cutting out and burned svt-7s ampeg sould be give schematics and intronctions to techicians all over the word because there are customers also out of us
that sufering with these problems and its out of there local waranty!!
 
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#20
limb said:
i think with all these numbers of cutting out and burned svt-7s ampeg sould be give schematics and intronctions to techicians all over the word because there are customers also out of us
that sufering with these problems and its out of there local waranty!!
Click to expand...

At one time, Ampeg used to provide a copy of the schematic on the inside of the amp. They were built to be repaired and the schematic was helpful to have. Any authorized service tech or any owner can request a copy of the schematic. Fender and other companies make their schematics available on their web sites. Other companies, like Ampeg, provide a copy upon request. Some companies do not make their schematics available.

As was mentioned, the 7Pro schematics are available on-line if you search.
 
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