[Milsurplus] PCB'S??

[Richard Brunner]

That's very good!  (Why didn't I think of that?)  The only virtue of
Askarels (PCB's) is they will not support combustion, and were used in
indoor and hazardous locations. (mines, etc.)  They also have a higher
dielectric constant than regular oil, so MIGHT be used to put more
capacitance in a can, but cost significantly more, so I would be
surprised if they were used often.  Askarel is also a good solvent.  I
once worked in a transformer factory, and when we had an Askarel
transformer the inside of the tank was unpainted, and there were no
glues or varnish in the transformer.

Richard, AA1P


On Sun, 2009-10-04 at 14:47 -0400, Al Klase wrote:
> Hi Ross,
> 
> Here's my thoughts regarding the presences PCB's in bathtub capacitors.
> 
> Poly-Chlorinated Biphenols are a class of oils used in indoor
> transformers, etc. because they are nonflammable.  I once saw a pole pig
> burn after a lightning strike.  You'd want to avoid that inside a
> building.  (If memory serves, PCB's were invented by Reginald Fessenden
> when he worked as a chemist for Tom Edison.)
> 
> However, I believe that small capacitors as used in receivers do not
> usually contain PCB as they just don't pose the same danger as 30
> gallons of hot oil in a transformer.
> 
> I recently removed an Aerovox bathtub form an RCA AR-88 receiver that
> had the sticky red seal syndrome.  I drilled a hole on the case and let
> it drain in a plastic cup for a while.  I picked up a sample of the oil
> on a Q-tip, took it outdoors, and held a match to it.  It burned pretty
> much like fuel oil.  I now feel much better about mopping up the oil
> inside the radio without taking annoying precautions.
> 
> Your mileage may vary.
> 
> Regards,
> Al