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Old 10th July 2007, 06:30 PM   #21
Bigred is offline Bigred  Canada
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The outputs I would bet are blown along with possible power supply damage. As Chris mentioned earlier... by just replacing the blown fuse numerous times you may have inflicked even more damage. For the future I wouldn't replace a blown fuse without ATLEAST some preliminary checking (it went for a reason). Anyways.... a good start I think would be to check Q107 thru 112
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Old 10th July 2007, 06:37 PM   #22
kevinkr is offline kevinkr  United States
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A couple of quick thoughts, perhaps Radio Shack can provide a schematic if you contact them via their website. Also it is possible that Sams Photofacts might have a schematic and service information for this model.

One thing working in your favor is it's old enough to be all through hole components, nothing like troubleshooting something with lots of smd parts as well.
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Old 10th July 2007, 06:44 PM   #23
anatech is offline anatech  Canada
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Hi Brian,
Just a thought.

What were you going to use this amp for?

-Chris
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Old 10th July 2007, 07:03 PM   #24
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Hey Chris,

Primarily for an in home "studio" for lack of a better word. I'm going to be driving a couple of speakers (maybe up to four) with output from a variety of sources through a 5 channel mixer.

- Brian
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Old 10th July 2007, 07:16 PM   #25
anatech is offline anatech  Canada
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Hi Brian,
This is only a single channel amp, isn't it? PA stuff generally dose not run in stereo.

-Chris
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Old 10th July 2007, 09:02 PM   #26
Bigred is offline Bigred  Canada
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Yeah this is a single channel. Can use it to run CD players and such but you obviously won't be getting stereo left and right separation
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Old 10th July 2007, 09:13 PM   #27
anatech is offline anatech  Canada
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It may serve you better if you feel like building a stereo amp of lessor power in that case, depending of course on how much you paid for it.

You aren't going to run four speakers unless you run them on a 70 V line, or use a series parallel connection for them.

-Chris
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Old 10th July 2007, 11:37 PM   #28
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Chris,

Thanks for the ?? re: application - I honestly didn't even think about stereo separation. Keeping that in mind - what do you think I should do? Does this one end up in the "bin"? Are there any components that would lend themselves to other applications? Ok, I'll quit asking questions..(for now!)

- Brian
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Old 10th July 2007, 11:40 PM   #29
Bigred is offline Bigred  Canada
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I guess the rest of us are invisible here. Good Luck with your pa amp
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Old 10th July 2007, 11:51 PM   #30
kevinkr is offline kevinkr  United States
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Quote:
Originally posted by 60fairlane
Chris,

Thanks for the ?? re: application - I honestly didn't even think about stereo separation. Keeping that in mind - what do you think I should do? Does this one end up in the "bin"? Are there any components that would lend themselves to other applications? Ok, I'll quit asking questions..(for now!)

- Brian
Depends on what you want to do, do you need stereo or will mono suffice? If you are interested in stereo one of the chip amp kits using the LM3886 might be just the ticket. There are several threads on the subject here. Otherwise you might still want to fix it.

Depending on power supply voltages the power transformer is definitely worth keeping as is that chassis and heatsink. You can probably package a kit amp in that box if you are a little creative.

There is undoubtedly a 70V/25V output transformer in this thing as well if it is for pa work. Does this unit have connections for high voltage lines - usually marked 25V or 70V out? For studio work this is generally not needed, and generally has rather poor bandwidth as well. The output transformer will have a bunch of wires going directly to the output connections on the back. (which I couldn't read unfortunately)
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