John,
> I can only buy one filter, wanting the most filtering for blood and
> guts 160 cw tests, but open enough to allow for fsk operation.
When you say FSK operation that fairly clearly puts a "400 Hz" lower
limit on the bandwidth and leaves you with two choices the 8830 KHz
(1st IF) filter or the 455 KHz (2nd IF) filter.
The 1st IF filter will provide a bit better RX IMD performance by
getting the "narrow" filter earlier in the IF chain but the 2nd IF
filter will provide slightly sharper skirts because of its lower
frequency. You can see the filter curves at www.inrad.net.
The 1st IF Filter is slightly less expansive than the 2nd. If it
were me, I'd flip a coin and get one now and pick up the second one
when conditions/finances allow. Ultimately you will want the pair.
73,
... Joe, W4TV
On 7/22/2012 6:57 PM, john wrote:
> I have bought back my 850 to use at my farm for dx/contesting/rtty.
> there seems to be large number options/filters/if crystals.
> due to finances I can only buy one filter, wanting the most filtering
> for blood and guts 160 cw tests, but open enough to allow for fsk
> operation.
> any and all suggestions would be appreciate
> mucho thanks....
> 73 john w8wej
>
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>
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