Driver Transformer - Solid State Leslie

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UnlikeKurt
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Driver Transformer - Solid State Leslie

Post by UnlikeKurt » Mon May 27, 2013 4:09 pm

I have a Leslie 825 amp and cabinet that I'm considering rebuilding. However, the driver transformer looks like hell. Is there a way to check it before going ahead with the rebuild of everything? The output of the amp is currently quite weak.

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Drone
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Post by Drone » Mon May 27, 2013 5:58 pm

There's various ways, from a quick impedance check of each side, which doesn't tell you much except the windings aren't O/C., to running a small signal into the secondary, and if you know the turns ratio, looking for the correspondingly large signal on the primary. That at least lets you know the turns ratio is OK, but nothing beats a load test.

What about it looks bad? Leaking wax? Burnt? Or a little rusty?
The previous statement is from a guy who records his own, and other projects for fun. No money is made.

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Post by UnlikeKurt » Tue May 28, 2013 3:56 pm

it looks like it could be a combination of burnt and rusty.
what would i do for an impedance check. can i do it in circuit or no?

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Drone
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Post by Drone » Fri May 31, 2013 12:14 pm

No, you'd have to take it out of circuit and just check for continuity on both sets of windings. Rust isn't bad, burning can be.
The previous statement is from a guy who records his own, and other projects for fun. No money is made.

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Post by UnlikeKurt » Sun Jun 02, 2013 10:46 am

i've pulled the transformer out. what can i do with my dmm?
There are two primaries and 4 secondaries
thanks

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Post by Scodiddly » Sun Jun 02, 2013 5:06 pm

Hook up one of the windings to a headphone output, and try hooking up a little speaker or headphones to the various other windings to see if they pass audio. There will likely be some big differences in volume.

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Post by UnlikeKurt » Mon Jun 10, 2013 7:27 pm

thanks fellas
i ended up testing it both with the ohm setting on a dmm and by passing some AC through it and measuring the secondaries. it's good to go so i'm good to go rebuild this amp.

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