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ph
Posted on Tuesday, July 16, 2002 - 01:42 pm:   

The lamp does not come on when I set it to the low power position, but only in the hi position. Is this something I should refer to a tech, or just a lamp change?
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Sean Shanahan
Posted on Tuesday, July 16, 2002 - 09:07 pm:   

I have the same "problem?" on my hd130 210
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Steve Kennedy
Posted on Wednesday, July 17, 2002 - 02:56 pm:   

Assuming you have no other problems related to Lo & Hi power switch positions, my guess is that you have a neon pilot light on the way out.

On older pre-1976/77 models, the selection of Hi & Lo power was made by switching taps on the primary AC side of the power transformer.

This means that the AC voltage & path to the neon bulb is different in the Lo position than it is in the Hi position.

As they age and get "gassy", neon bulbs require a higher turn on voltage. This means that your two conditions (Hi & Lo Power) are different enough to cause your particular lamp to turn on in only one of these positions.

You can either try to disassemble the pilot light assembly and replace the neon bulb, or simply replace the whole assembly.

On the newer amps, the neon lamp sees the same AC primary voltage in both output power positions because the selection is made at the output (secondary) side of the power transformer and is isolated from the pilot light circuit.

Steve

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ph
Posted on Thursday, July 18, 2002 - 07:40 am:   

Thanks

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