Hello
I have a Belles amp, Reference 150A V2 that quit working in the left channel. I opened the top and there is a light smoke film on the transistors. I called Dave Belles and he said to send it to a gentleman in New York for repair. I live in Colorado so I don't want to if I don't have to. So I have been asking for a good technician that could do it here in Colorado. I haven't found one yet. I am not afraid to try it myself, if I had some guidance. In high school (50yrs ago ) it took a couple of years of TV and radio repair so I can solder a little bit. If someone could probably tell me what I need to know that would maybe get me started. But not ever doing it before I can realize maybe I shouldn't. But I was thinking a couple of things I need to know. One, how do I go about getting the correct transistors. I have the numbers but I cannot find an exact number replacement. And then do I need to match them for compatibility, not npn and pnp, but individual measurement matching, if so I don't know how to do that. And then biasing them I don't know how to do that either. I am kind of helpless maybe. If anyone could provide some guidance I would appreciate it. The last I heard Mr Belles doesn't give out schematics on request. Thank you
I have a Belles amp, Reference 150A V2 that quit working in the left channel. I opened the top and there is a light smoke film on the transistors. I called Dave Belles and he said to send it to a gentleman in New York for repair. I live in Colorado so I don't want to if I don't have to. So I have been asking for a good technician that could do it here in Colorado. I haven't found one yet. I am not afraid to try it myself, if I had some guidance. In high school (50yrs ago ) it took a couple of years of TV and radio repair so I can solder a little bit. If someone could probably tell me what I need to know that would maybe get me started. But not ever doing it before I can realize maybe I shouldn't. But I was thinking a couple of things I need to know. One, how do I go about getting the correct transistors. I have the numbers but I cannot find an exact number replacement. And then do I need to match them for compatibility, not npn and pnp, but individual measurement matching, if so I don't know how to do that. And then biasing them I don't know how to do that either. I am kind of helpless maybe. If anyone could provide some guidance I would appreciate it. The last I heard Mr Belles doesn't give out schematics on request. Thank you
More parts could be damaged than just the output transistors.
It would be more difficult than just replacing those, you'd have to troubleshoot
and understand how to find the other bad parts, and why they are bad.
And understand when the amplifier is fixed and working properly.
You'll need several pieces of test equipment to do the work as well.
But first you need the schematics, if only for the local repair technician to use.
Frankly, if Belles won't repair it, and he won't give you the schematic, why would
you want to own that amplifier? There are lots of other good amplifiers (with schematics).
For the money you'll have to put into it to get it fixed (including shipping both ways),
you could probably buy a brand new amplifier, instead of being stuck with one that
the designer refuses to support. His "intellectual property" is more important to him
than customer service, it seems. Consider selling it on ebay "as-is" for parts or repair.
The guy in New York would probably buy it, fix it, and resell it on ebay.
It would be more difficult than just replacing those, you'd have to troubleshoot
and understand how to find the other bad parts, and why they are bad.
And understand when the amplifier is fixed and working properly.
You'll need several pieces of test equipment to do the work as well.
But first you need the schematics, if only for the local repair technician to use.
Frankly, if Belles won't repair it, and he won't give you the schematic, why would
you want to own that amplifier? There are lots of other good amplifiers (with schematics).
For the money you'll have to put into it to get it fixed (including shipping both ways),
you could probably buy a brand new amplifier, instead of being stuck with one that
the designer refuses to support. His "intellectual property" is more important to him
than customer service, it seems. Consider selling it on ebay "as-is" for parts or repair.
The guy in New York would probably buy it, fix it, and resell it on ebay.
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Well that was what I need to know. I do realize a need to find out the cause of why the transistors went out. Thanks
Need test equipment.
And step by teaching course and diagnoses on the internet is difficult.
If you think finding a tech is hard now.
It is even worse and dealt with all the time.
Someone tries to repair a amp, and does more damage.
Then the next guy has to repair the damage done, then figure out the original problem.
far as I can tell this is a lateral mosfet amp using Exicon transistors.
And step by teaching course and diagnoses on the internet is difficult.
If you think finding a tech is hard now.
It is even worse and dealt with all the time.
Someone tries to repair a amp, and does more damage.
Then the next guy has to repair the damage done, then figure out the original problem.
far as I can tell this is a lateral mosfet amp using Exicon transistors.
That is a $3000 amp, compared to that shipping cost is trivial.
Why am I not surprised?
Who will troubleshoot it for you, by remote control, with nonreliable data?
Or no data at all.
Minimum 4-5 years Electronics Course + minimum 3-4 years as an apprentice at a working shop.
Not sure that is enough, at all, lots of very probable problems.
MANY don´t, specially to unaccredited end users, but he did the next best thing: he directed you to somebody who can repair it.
Please do that.
