Make your own!
Use this site to design your filter.
http://www.iowahills.com/9RFFiltersPage.html
Attached are the values I used back in 2016 when the G4AQG FT-1000MP had
intermod problems with a new Beverage.
I built a 9 pole Chebyshev high pass filter, designed with the excellent RF
filter design package from Iowa Software, and used an LC meter to get the
capacitor and inductor values correct. Caps were made from polystyrene and
inductors wound on small ferrite torroids..
Difficult to see from the (ancient!) spectrum analyzer picture but the filter
response was almost exactly as the design showed.
No labels for stop-band but it was 10dB down at 1579kHz, 50dB down at 1000kHz
and at 693kHz was in the noise, at least 70dB down, almost undetectable
compared to 60dB over S9 or more without the filter, and the intermod was gone.
> On 16 Apr 2020, at 19:34, Edward via Topband <topband@contesting.com> wrote:
>
> Greetings,
>
> I am getting clobbered by a local BCB transmitter, making 160M unusable, even
> with a dedicated RX antenna.
>
> As for filters, I have narrowed it down to the ICE and the Kiwa. Kiwa seems
> to be the more serious filter, as they publish their specs in great detail.
> ICE does not.
>
> Any other filter I should consider besides these two?
>
>
> Thanks,
> Ed 7Z1ES
> _________________
> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
73,
Jeremy Maris
G3XDK / G4AQG
_________________
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
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