[R-390] Filters

Charles P. Steinmetz charles_steinmetz at lavabit.com
Sat Feb 16 16:09:30 EST 2013


>OK, big problem.  When I pulled the bobbin out of the top side 
>(output) there is no central wire.
>      *   *   *
>Woops, I just found the wire.  Now how to attach it back to the end disk?

I presume it was originally welded, probably with some sort of 
spot-welding process.  If you get the cup and coil out of the way so 
you have a clear view of the disk, it should be easy to tell.  If it 
was welded, I suspect that you'll need to re-weld it to repair it.  A 
tiny drop of really, really good epoxy might work, but I wouldn't 
hold out much hope that it would last.  Note that the wire probably 
needs to be placed on the disk with reasonable precision to get the 
mechanical impedance right.

Best regards,

Charles






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