EMRFD Message Archive 13653

Message Date From Subject
13653 2017-03-04 12:39:30 bob_ledoux Disc Ceramic Capacitor "Adjustments"
I'm building a new 5 crystal, 8 Mhz SSB filter.  The design calls for some odd value capacitors.

The 42pf caps are pretty rare and none of my 47 pf were close, as measured on my AADE LC meter.

So I pulled out my Dremel tool with a sanding drum.  Grinding off the top of the caps I was able to bring the caps to within 1% of desired value--limited by the accuracy of the AADE meter.  A bit of Sally Hansen Nail Hardener sealed the capacitor tops.

I'd read about this process but this is the first time I've tried it.  It is remarkable to witness. 

The cap must be a value above the desired target value.  I don't think I'd try turning a 100pf into a 22pf. 

bob-N7SUR


13657 2017-03-05 10:04:32 Frank Dinger Re: Disc Ceramic Capacitor "Adjustments"
Hi Bob , N7SUR  ....excellent experience advice , "dressing" ceramic caps.

Tnx , Frank , GM0CSZ / KN6WH      in IO87AT