> Date: Mon, 10 Jan 2011 14:25:26 -0500
> From: olinger@bellsouth.net
> To: k6uj@pacbell.net
> CC: topband@contesting.com
> Subject: Re: Topband: Russian Vacuum Variables on EBAY
>
> Bought two 1200 pf 4 kV for use on big 160 antennas out at N4AF, from
> QRO-stuff. No problems and have done the job out in remote box for
> seven or eight years now. Very stable. Quite large, drive shaft is
> NOT 1/4, 12mm or almost 1/2. Most likely have to fabricate a knob or
> reducer.
>
> Those big things are the final answer, absent direct lightning
> strikes, for going the distance QRO. Prices for Jennings brand new
> retail are simply awful new, but on eBay the Russian listings are
> affordable. This is most like what we bought:
>
>
http://cgi.ebay.com/Vacuum-Variable-Capacitor-10-1200-pF-4kV-New-Box-/200563805228?pt=LH_DefaultDomain_0&hash=item2eb288cc2c#ht_2455wt_1139
>
> 73, Guy.
> ************************************************************
> On Sun, Jan 9, 2011 at 9:00 PM, Robert Harmon <k6uj@pacbell.net> wrote:
> >
> > I see some good prices on new Russian vacuum variables on EBAY. Thinking
> > about getting several
> > for a vertical tuning unit I am planning. Anyone bought vac vars from the
> > Russian EBAY vendors,
> > good results ?
> >
> > tnx es 73,
> > Bob
> > K6UJ
*****************************************************************
I've just looked at this auction listing, as well as visiting:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260712022418&ssPageName=STRK:MEWAX:IT#ht_2850wt_302
which is now closed.
The prices shown, plus shipping, are just a bit north and south of $200 for
these glass-encased capacitors.
On my desk is a Jennings CMV1-650-0005 that I cannot distinguish from new, and
it arrived here last week for $195, plus a nominal amount for shipping from
Marietta, GA, USA. Transit time via FedEx was 48 hours. It is ceramic, less
fragile than glass, offering 8-650 pF @ 5kV. and with 10 turns' rotation
required for its min.-to-max. capacitance variation. The 0.5-inch diameter
shaft came with a reducer to 0.25-inch diameter, mounted by the seller.
Fitting a 10-turn dial will be easy.
This gem will be set to about 255pF and then installed at the base of my 0.37
wavelength (85'up + 85' out) inverted L antenna where, aided by 44 in-ground
radials with an aggregate length of just under a mile, it will replace a large
"bread-slicer" capacitor and restore my 1.1:1 SWR reading. I feel quite safe
that with such a generous breakdown voltage rating I shall have no problems
with my almost-always output power of five Watts, but I must give a bit of
thought to better protection from lightning damage.
This capacitor's seller is the well-known and long-established, MaxGain
Systems, whose principal I deem to be a worthy and reputable individual. He
knows much more about vacuum variable capacitors than I can ever hope to learn,
and, in my estimation, he has the integrity to willingly settle fairly any
problem that might arise from a business dealing with his company.
Over the Christmas holiday I read the The Economist of 11 December 2010, pages
29-32, "Briefing: The State of Russia", which I highly recommend, and from
which I now believe a likely consequence of my recent purchase to be my not
having dealt in stolen goods; nor did I worsen the US' balance of payments
deficit by adding to this country's substantial trade imbalance.
73 (or perhaps QRP-speak 72),
Charles, W2SH
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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