Scott - I believe you are correct. I spoke with Mike at ICE today,
and without putting number on it, he said "adding the second filter
would produce an additive effect somewhat less than twice a single
filter." I interpret "somewhat" closer to 20 db than 6 db.
Also, the 170W present on antenna 2 with 1500W transmitted on
antenna 1 was a theoretical model generated by EZNEC, placing a
50 ohm load in place of the source on the second antenna
(suggested method by W7EL). Mike suggested it would be
significantly less, which I intend to verify once the antenna is up by
putting a wattmeter in the line of the rcve antenna and connecting it
to a dummy load (NOT a transceiver!) while transmitting on the first
antenna.
I'll report back my findings once the antenna is up (probably not
until fall with the hot wx we've been having!)
73 Barry
On 2 Jul 99, Scott Ellington wrote:
> That said, however, cascading a second "40 dB" filter with the first will
> probably yield a big increase in attenuation. Perhaps not 40 dB, but probably
> more than 20. My guess is that with two of the ICE filters, the limiting
> factor would be leakage around the filters, unless great care is taken.
>
> 73,
>
> Scott K9MA
> --
>
>
> Scott Ellington
> sdelling@facstaff.wisc.edu
> Madison, Wisconsin USA
>
>
> --
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>
--
Barry Kutner, W2UP Internet: w2up@mindspring.com
Newtown, PA FRC alternate: barry@w2up.wells.com
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