Well John .. I RE-iterate .. if you are using back to back caps, it does
NOT matter if they are plus to plus or minus to minus -- my injection into
discussion was NOT about whether it was a good engineering practice to use
that method for the final product! You lost the thread of the thread. The
point was whether or not the TEMPORARY caps had to be oriented any
particular way ..to test the circuit in question, and fix the darn thing --
or make the rotator, or whatever, WORK .. as in like, during November
Sweepstakes, at 2 AM Saturday, when the darn thing has a fit .. you know
that scenarario!. .As a retired broadcast / 2-way engineer, and a hammer
for a long time having installed many many aerial systems, I feel qualified
to speak on SOME things, but am obviously not as versed on the subject as
you! Love your stack! (PS -- hope I get to go up to KL7 next year and help
RA re-install his antenna system! Going to be KEWL!) 6dx
----- Original Message -----
From: "W0UN--John Brosnahan" <shr@ricc.net>
To: "Mark" <AA6DX@arrl.net>
Cc: <towertalk@contesting.com>
Sent: Monday, August 05, 2002 3:36 PM
Subject: Re: [Towertalk] Tailtwister won't turn.
>
> At 03:13 PM 8/5/2002 -0700, Mark wrote:
>
>
> >Why? Does not matter, but the practice is fine! I do things by habit,
> >too.... It is AC .. does NOT matter.. pluskies or minusers...just back to
> >back.. did it for years in speaker crossovers as well as motor starting
> >capacitors .. as we are discussing and reading about here. Mark 6dx
>
> We are talking POLARIZED electrolytic caps here--it DOES matter.
> You can get away with it (sorta) with audio because the voltages
> typically are not that great--but they really need to be back to back
> and ideally with diodes across them to eliminate the reverse voltage
> in motor-starting applications.
>
> The real question is whether you need to divide the effective capacitance
> by two. The caps are really NOT in series in the classical sense--but
rather
> one cap handles the half cycle voltage of one polarity with the
capacitance
> with which it is marked. Then the other cap handles the other polarity
> half-cycle with its capacitance. So it seems to me that maybe the
> effective value does not need to be halved.
>
> --John W0UN
>
>
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