🚀 go-pugleaf

In article <17u3gbINNfuv@darkstar.UCSC.EDU>, haynes@cats.ucsc.edu (Jim Haynes) writes...
> 
>I've got this circuit which consists of
>   8:1000 ohm input transformer feeding
>   DIP bridge rectifier feeding
>   base-emitter junction of a transistor.
>The idea is to connect the 8-ohm input to the output of a radio or
>tape recorder and turn on the transistor when there is some signal.
> 
>It works fine, at first.  After it sits for a while, turned off, it
>won't work.  Then I disconnect one of the secondary leads from the
>transformer, observe with an AC voltmeter that there is voltage there,

	Ah yes, but there is also probably DC voltage there.

	When you put ac on top of dc into a transformer, the resultant
	E-H curve keeps jacking up the magnetic field until it saturates.

	Try putting a large cap in series with the transformer primary to
	block the dc component.
	

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