Topband: FT1000 MKV Filters
shristov at ptt.rs
Fri Jul 25 07:37:26 EDT 2008
Raoul Coetzee <raoulc at smmcape.co.za> wrote:
> I have currently a 500Hz Collins filter and a 250Hz Yaesu filter
> installedin the main receiver of my FT 1000 MkV. I found that I use the 250Hz filter
> most of the time for weak dx on 160m, without any DSP noise reduction. I
> would like to know if there would be any advantage installing the second IF
> filter, centre frequency of 8.215, of also 250Hz. I do not have strong
> signals close by, therefore I have also not looked at a roofing filter yet.
For weak signal work with no strong signals capable of overloading RX stages,
there is no advantage in installing 250 Hz at 8215 kHz IF.
Operating comfort may be increased slightly by a narrow filter, such as
Inrad's 125 Hz at 455 kHz IF, or the built-in 60 Hz DSP APF. They will
bring up signals that you wouldn't hear otherwise, but you may prefer
the reduction of noise.
Do not use 120 Hz DSP APF as is has a valley in the passband center.
Apart from properly adjusting your receiver,
the only way to improve reception is to have better antennas.
Sinisa YT1NT, VE3EA
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