[Milsurplus] Micamold caps

[WA5CAB at cs.com]

Brad & Rich,

No, you will not find any current production in the original size and ratings 
or brown.  Most are going to be yellow for some reason not known to me.  And 
they are going to generally be smaller for the same voltage rating because 
improvements in materials over the past half century+ have resulted it smaller 
parts.  And for some reason (probably to save a fraction of a penny or some 
other currency) current parts (resistors and capacitors) also use significantly 
smaller gauge wire which makes them less satisfactory to work with.  But there's 
nothing we can do about that.  

My rule in replacing capacitors and resistors is that if it's bad, replace 
it.  If it ain't broke, don't fix it.  My experience and practice with 
capacitors in BC-312 family, BC-348 family, BC-1306 family and similar vintage military 
sets is that if I find two of a particular value and type capacitor bad 
(including canned, micamold or any other mechanical type), I start checking the 
rest, starting with the easiest to get at.  If the third one is bad or even 
questionable, I replace all of them.  In the BC-312 family, there are a batch of 
canned triple .005 ufd capacitors.  Generally, they are either all good or they 
are all bad.  However, here the replace all after finding the third bad one 
rule applies to triples, not to three in one can.

But keep in mind when checking capacitors that if there is any shunt 
resistance in the circuit, you can't believe the capacitor tester until you've removed 
(disconnected one end of) the shunt.

In a message dated 11/23/2006 12:33:57 AM Central Standard Time, 
richard.arland at verizon.net writes: 
> I have a BC-312 that I am going to restore later this winter. I was 
> wondering the same thing...are the Micamold caps worth the hassle? I'm 
> interested in the replies you might get on this question. Al Klase, N3FRQ, 
> told me that they were a real pain in the tail to replace. Just wondering if 
> 
> it is worth the trouble.
> 
> 73 Rich W3OSS
> 
> 
> From: "Brad Latta" <bl_6000 at yahoo.com.au>
> 
> 
> >Just wondering about these black Micamold caps in this
> >BC-348. Is it worth replacing them all?? If so,
> >is there a modern equivalent with the same size &type
> >of mould, &a similar voltage rating? They don't seem
> >to have a sharp resonance 'dip' when measured on my
> >capacitance bridge.
> 

Robert & Susan Downs - Houston
<http://www.wa5cab.com> (Web Store)
MVPA 9480
<wa5cab at cs.com> (Primary email)
<wa5cab at houston.rr.com> (Backup email)
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