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300 would probably be OK for PSK, but if you wanted to try MFSK or
some other data modes it would be too narrow, so 500 would give
greater versatility.

Julian, G4ILO

--- In FT817@y..., "Jan and/or Len Peak" <peaks@p...> wrote:

Hey Gang,What would be best a300 or500hz filter for CW if one was

going to

do PSK-231??Len

Hey Gang,What would be best 300 or500hz filter for CW if one was
going to do PSK-231??Len

With PSK31, the real bandwidth you use is set by the DSP filters in
the soundblaster-based PSK31 software you use. The reaso for using a
narrower bandwidth filter is to reduce the clutter & intermod & AGC
pumping & SoundBlaster dynamic range problems.

Here I'm using the INRAD 500 Hz filter (which seems closer to 600 Hz
in practice) and it works well. As a hint when you use such a filter.
Push the CLAR button for 1+ seconds, and the SEL knob becomes a
passband tuning control. This can be used to select the stations that
are in the passband. Often I can push an offending "bad-guy" off the
edge by using this PBT control.

Here I found that if you set #26 DIG=PSK31-U, toggling the filter
on/off causes a ~30 Hz frequency shift. Instead, set #26 DIG=USER-U
and this annoying bug goes away.

73 de Tom, W3IWI

please note, that with the optional CW- Filter installed and using
PSK31-U with NAR filter on, you are most likely NOT TRANSCEIVE !
I mean, that bandpass is offset by about -200Hz, when switching NAR
on or off, but your transmitter is always on the USB-Wide passband
and so you transmitt on a different QRG than you receive, with the CW
filter on!
the only workaound I found is to use DIGITAL MODE SETTING: USER-U
instead of PSK-U
Any other comments?
vy 73 de oe3mzc@...
Mike
--- In FT817@y..., "Dr Thomas A Clark" <w3iwi@y...> wrote:

Hey Gang,What would be best 300 or500hz filter for CW if one was
going to do PSK-231??Len

With PSK31, the real bandwidth you use is set by the DSP filters in
the soundblaster-based PSK31 software you use. The reaso for using

a

narrower bandwidth filter is to reduce the clutter & intermod & AGC
pumping & SoundBlaster dynamic range problems.

Here I'm using the INRAD 500 Hz filter (which seems closer to 600

Hz

in practice) and it works well. As a hint when you use such a

filter.

Push the CLAR button for 1+ seconds, and the SEL knob becomes a
passband tuning control. This can be used to select the stations

that

are in the passband. Often I can push an offending "bad-guy" off

the

edge by using this PBT control.

Here I found that if you set #26 DIG=PSK31-U, toggling the filter
on/off causes a ~30 Hz frequency shift. Instead, set #26 DIG=USER-U
and this annoying bug goes away.

73 de Tom, W3IWI