,
wrote:
>
> On Sun, 8 Nov 1998, John Robertson wrote:
>
> > Hmm the problem would be the same as is currently happening, except you
> > would probably blow up your speakers if the outputs are bad...
>
> Not if you AC-couple the outputs to the speaker....
Ohhhh, now I'm feeling stupid...That would work fine.
>
> If the outputs are bad, it's usually because one/both of the def.
> transistors are shorted -- causing the output to hit a rail...
>
> > The idea here is to run the XY amps unloaded so as the output
> > transistors don't croak if the drive is bad. Perhaps a resistor, say 100
> > ohms might be enough of a load to test. I'm trying to find a simple way
> > to power the monitors (I have about six or so) without having to have a
> > running game board, nor do I want to toast the outputs by having hte
> > yokes connected. Soon this will be happening. Is anyone interested in
> > tested working 19" XY's? Somewhere around $250-$300US... May have my HV
> > hack...
>
> Out of curiousity, when have you run into a situation when the
> pre-amps blew out the output stage in one of these monitors? Usually
> it's the other way around, in my experience -- a bad output stage txtor
> will take out one of the pre-drivers.
>
> Joe
Hmm, well not sure about that, I've last really worked on those things
back in the 80's, so recolection is slow (must be ferrite core memory),
but I do recall a few monitors that had bad connections (Electro's
mostly) and this would blow the outputs, inputs and everything else...
John :-#)#
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