Evert,
When using SSB, it is usually easier and better to use the HI CUT/LO CUT
rather than width and shift. Just reducing the HI CUT will usually
result in a narrowed bandwidth but maintains intelligibility.
The BFO/Filter relationship should be preserved with the low end between
250 and 300 Hz for best intelligibility with a narrow SSB filter - using
Hi Cut allows you to easily achieve that. You might want to tweak the
Lo Cut setting a slight amount, but the bandwidth reduction for a SSB
signal should be mostly from the high frequency end.
73,
Don W3FPR
Evert Bakker (PA2KW) wrote:
Hello all,
Today I received the 1.8 Kc 8 pole filter and installed it tonight.
I did the configuration with the software tool used for firmware updates as
well (also performed an update as well).
All went OK, but I do have a feeling something is wrong or my ears/brains
work a little different from the majority (yeh yeh I know...)
When XFil 2.7 is selected together with the DSP at 2.7 Kc, the audio sounds
great. When decreasing the BW with the DSP to 1.8 (but keeping the centre
the same), the hardware filter is switched in at 1.8 Kc DSP setting. During
the decreasing process I'm loosing "information" (Ofcourse!) but my feeling
says too much. When during the decreasing process I also lower the centre
freq, the excessive loss of "information" is compensated. This gives me the
feeling as if the filter isn't centered anymore.
First I thought this might have to do something with the Offset (-0.91 for a
2.7 5 pole filter) but nothing was written on the 1.8 Kc 8 pole filter. I
just tried it, but that didn't compensate the excessive loss.
During a process of decreasing bandwidth while listening to an SSB signal, I
would appreciate if a shift of the centre-freq of the DSP is not required
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
