Transformer test rig

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rfgordon
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Joined: Tue May 02, 2006 12:59 am
Location: Virginia
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Transformer test rig

Post by rfgordon »

You guys are prolly way ahead of me on this, but I figgered I'd pass this on anyway.

A friend let me borrow a copy of a new (to us, anyway) mag called Premier Guitar. In the April issue is a tech piece on making a cheap transformer tester.

1. Solder a 100k resistor in series with one leg of a NE-2 neon bulb.
2. Cut a clip lead in two pieces, and solder one to each leg of the bulb assembly.

To test whether a tranny has a short across one winding, disconnect all leads and put the neon clips onto the legs of the winding to be tested.

Pick a lead on the other side of the tranny (primary, if you're testing the secondary), and briefly touch the leads to a battery, then release. If there is no short, the collapsing field will induce a voltage on the other side and cause the neon bulb to flash. No flash means a short. The author uses a 6 V lantern battery.

I haven't tried it yet, but I plan to get the neon bulb and do it.
Rich Gordon
www.myspace.com/bigboyamplifiers

"The takers get the honey, the givers get the blues." --Robin Trower
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