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Linrad use on 160 meters

Hi All.

On 21 Jul 2003 at 18:35, Leif Asbrink wrote:

> Hi Bill and all,

> Linrad01-04 will have AGC so it can be used in full for normal
> CW and for SSB.

Nice. I am hoping to use Linrad for terrestrial SSB on 2M, so
AGC will be very handy for handling strong signals.

 The automatic carrier adjust for SSB is not in 
> place, it is low on the priority list.

Automatic carrier adjust? Is to to imply that it is possible
to properly tune SSB automatically rather then by ear?
That would be nice. I was wondering how SSB could be
tuned with point and click tuning. I suspect that currently
you would have to make a guess and click on the desired signal
and keep clicking util it sounds right...?

> Next is a mode for QRSS.
> Just a second waterfall graph using the baseband spectra that 
> may be set for really narrow bin widths. I have some recordings
> from 137kHz. The VLF noise floor has several different types of
> QRN in these recordings and I think they will be fine for
> implementing the baseband waterfall and the baseband noise blanker.

I think the Lowfers would find this very useful too. The 160 -190 Khz
band is 30 Khz wide, so in theory someone could watch the entire
band for QRSS signals. In practice, most of the signals are clustered in the
top 10 Khz of the band, so if 30 Khz bandwidth is not practical, then
perhaps 10 Khz is.  QRSS speeds between QRSS3 and QRSS60 (60 second dots)
are commonly in use and 1000 mile reception reports are becoming common
in Winter months with part 15 stations (1 watt, 50 foot vertical).
If Linrad works anything like Spectran, then I would expect the spectrum display
bandwidth to be more narrow when QRSS settings are used.
For example, in Argo when I use the QRSS3 setting for fine tuning EME signals,
only 100 hz of screen display bandwidth is available.
I would also like to see the individual dots and dashes on screen as I copy
normal 15 WPM CW off the moon, in case my brain crashes and I did not
copy something that I should have been able to. I have noticed that with
programs like Spectran, it is possible to read CW off the screen when
CW copy is only moderately strong (I.E. stations similar in signal strength
to my own 4 yagi signal). It would be nice to be able to do this without 
using a second computer looking at station audio.

> 73
> Leif

73, Jim Shaffer, WB9UWA.