You can protect your receiver by using crystal filters as
preselectors. However, they are expensive and only cover
a few 10's of kHz. Also, they have their own nonlinearities,
so a really strong interfering signal might cause intermods.
You need some tricky switching system to switch the filter
out on transmit.
Unfortunately, this scheme presupposes the transmitter is
clean. You may find you are still having trouble even
with the crystal filter. Of course you cannot put a crystal
filter on the transmitter.
An LC filter that could be used with a transmitter cannot
be made narrow enough to pass phone and reject CW or vice
versa. Or if it could, it would be *very* difficult to build.
You might want to experiment with separate receive antennas
that you can orient so as to null the other station.
In the TBDC contest, I used a loop receive antenna to null
my own transmitter signal. This allowed me to operate
SO2R on the same (160m) band. I could receive within 5 kHz of
my own signal. I estimate that I got 60 to 80 dB of nulling.
Rick N6RK
John Hudson wrote:
> This may be off topic a little but I'm looking for some help
>
>
>
> Our club operates typically 3A during FD with one dedicated CW station and
> 2
> phone stations and running dipoles and this year the clubs A3S.. We are
> looking for some band-pass filters to help with the interference between
> the CW/Phone stations. We currently have ICE filters but they are cut for
> the complete bands (14.000 - 14.350, etc). Does someone make a inline
> filter
> that will isolate the phone & CW portions??
>
>
>
> Looking for hints, tips and suggestions and please contact me off list.
> ko4xj@arrl.net
>
>
>
>
>
> 73
>
>
>
> John
>
> KO4XJ
>
> www.w4nja.org
> www.w4nja.org/ko4xj.htm
>
>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
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