Hi Steve,
In 1990, I measured the Q of the LCA loading coil on the 40-2CD with an HP
"Q" Meter. It measured a Q of 210 with C of 39 pFd. and parallel (or Rp) of
about 108K Ohms. At 2.52 MHz it had a Q of 150.
Subsequently, as I recall, W6NL, Dave Leeson either measured or calculated
the Q at 150.
Take your pick.
73,
Joe, W1JR
At 02:43 PM 4/2/2003 -0700, ve6wz wrote:
>Is there anyone out there who has **MEASURED** the Q of a Cushcraft 402-CD
>or XM-240 (shorty 40) loading coil.
>
>I have read quotes of around 3 ohms of loss, but some software inductor
>programs suggest a much lower Q of 62 with 8 ohms loss!! This low Q is
>because of the form loss associated with the fibreglass core.
>
>These coils are 68 turns of 12 ga. copper on a 3/4" fiberglass rod.
>
>Any one put one of these coils on a Q meter ??
>
>
>de steve VE6WZ. http://www.qsl.net/ve6wz/index.html
>_______________________________________________
>
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>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
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>
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