>
>FWIW, a blocking capacitor rated @ 20,000 volts and enough current
>to handle 2+ KW on 10 meters would be about the size of a
>mayonaise jar. A good rule of thumb on RF doorknobs is to
>look at the threads at each end. If they are #10 X 32 or larger,
>you are in the ball park in the current dept.
Agreed. Sprague made some 1800pF 40kV units that were about 1.8" tall
and a bit over 2.4" in diameter. These were not current rated even
though they worked ok with 4cx10,000As. Murata makes capacitors for
continuous DC blocking duty in large amplifiers.
>
cheers, Phil
>
>>
>> Paul: By any chance did you pick up that cap at HamCom last weekend? I
>> saw something like you describe there. I believe they were mylar
>> dielectric foil jobs. If so, they probably have resonance problems and I
>> would be skeptical about high current application in spite of the HV
>> rating. 73, Dan, N5AR
>>
>> Paul and Abbi Elliott wrote:
>> >
>> > Bought a capacitor at a flea market that I am trying to identify in hopes
>> > that it would be satisfactory for a plate blocking cap in a legal limit
>> > amplifier. Put it in series with my 160m antenna lead to test it (on a
>> > dead band in the middle of the day), and it didn't even get warm from a
>> > couple of minutes key down); but since I can only muster about 3 amps in
>> > that set-up, I don't think the test is severe enough to tell me what I
want
>> > to know.
>> >
>> > Some artist got turned loose on the name on it--has a "C" with some symbol
>> > surrounding it--that all I can figure out, by context, is supposed to be
a
>> > "u" (doesn't look like one to me!) since the last letters are "stom".
>> > Right below the name are the following:
>> >
>> > CMR3A14OSP
>> > .000625 microfarad plus or minus 5%
>> > 20,000 WVDC
>> > 532036-1
>> > 8720
>> >
>> > Physical dimensions are: 1 1/2" W x 5/8" D x 4 1/4" L. Has 1" x1/2"
metal
>> > strap connectors on each end. Body color is yellow, and the ends are red.
>> >
>> > Can someone, who either has the knowledge or catalog information, please
>> > tell me whether the current carrying capacity and dielectric properties
are
>> > suitable for a plate blocking capacitor in a legal limit amplifier--about
>> > 4000 VDC at 700 ma--from 160m thru 10m?
>> >
>> > Thanks for any help.
>> >
>> > 73
>> >
>> > Paul W5DM
>> >
>> > --
>> > FAQ on WWW: http://www.contesting.com/FAQ/amps
>> > Submissions: amps@contesting.com
>> > Administrative requests: amps-REQUEST@contesting.com
>> > Problems: owner-amps@contesting.com
>>
>> --
>> FAQ on WWW: http://www.contesting.com/FAQ/amps
>> Submissions: amps@contesting.com
>> Administrative requests: amps-REQUEST@contesting.com
>> Problems: owner-amps@contesting.com
>>
>
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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