[GreenKeys] Frequency diversity radioteletype experiments

[Joe Montano]

When I was active duty USAF, one of the crews I was assigned to ran
MD-522s, MD-1142s and MD-1061s in various configurations for both time and
frequency diversity as an experiment/training mission.

That was a great FTX.

On Mon, Oct 12, 2026 at 1:30 PM Harold Hallikainen via GreenKeys <
greenkeys at mailman.qth.net> wrote:

> That sounds great! The 2805 Hz is pretty high for an SSB transceiver.
> Also, it seems that the levels of the simultaneous tones have to be kept
> down since their amplitudes add. I wonder how this compares with just
> running wide shift (say 2 kHz) with dynamic threshold control.
>
> I want to experiment some with space diversity. It will not be as fancy as
> having two receivers and a diversity TU. Instead, I'll just switch
> antennas whenever the TU is in mark hold. There will be errors, but
> ideally there will be better copy in a long fade.  A TV satation I worked
> with did this on a microwave receiver. There were two dishes on the tower.
> During a fade, they would switch to the other dish.
>
> The 8:30 AM ET is a bit early for me being on MST. But I'm almost always
> on 14.086 MHz LSB (14.083,875 MHz Mark, 14.083,705 Space) autostart during
> the day.
>
> Harold
> https://w6iwi.org
>
>
> On Mon, October 12, 2026 7:32 am, Nick England via GreenKeys wrote:
> > Ron K3TZJ, John K9WT, and I had very nice QSO/test session last week and
> > today using the MD-522 diversity mode for radioteletype. It worked very
> > well indeed at overcoming fading and QRM. This mode sends identical 85 Hz
> >  shift tones centered at 425Hz and 2805Hz. Come join us or listen in.
> > Monday 0930 EDT. 7087kHz USB. Mark low. 45 baud.
> >
> >
> > And don’t forget our regular Saturday morning 850 shift net starting
> > around 0830 EDT also on 7087 USB (2000 Hz center). A couple of the
> fellows
> > have used spatial diversity for receiving on that net, with two different
> > antenna/receiver channels feeding a diversity combiner TU.
> >
> > Remember, if you don't have a short wave receiver that you can always
> > listen in via web SDR http://www.websdr.org/
> > http://kiwisdr.com/public/
> >
> >
> > Have fun,
> > Nick England K4NYW
> > Chapel Hill NC
> > www.navy-radio.com
> > ______________________________________________________________
> > GreenKeys mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/greenkeys
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:GreenKeys at mailman.qth.net
> >
> >
> >>>> Jordan Spencer Cunningham's GreenKeys Search Tool:
> >>>> https://teletype.net/gksearch
> >>>> 2002-to-present greenkeys archive:
> >>>> http://mailman.qth.net/pipermail/greenkeys/
> >>>> 1998-to-2001 greenkeys archive:
> >>>> http://mailman.qth.net/archive/greenkeys/greenkeys.html
> >>>> Randy Guttery's 2001-to-2009 GreenKeys Search Tool:
> >>>> http://comcents.com/tty/greenkeyssearch.html
> >>>>
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to harold at w6iwi.org
>
>
> --
> Not sent from an iPhone.
> ______________________________________________________________
> GreenKeys mailing list
> Home: http://mailman.qth.net/mailman/listinfo/greenkeys
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:GreenKeys at mailman.qth.net
>
> >>> Jordan Spencer Cunningham's GreenKeys Search Tool:
> https://teletype.net/gksearch
> >>> 2002-to-present greenkeys archive:
> http://mailman.qth.net/pipermail/greenkeys/
> >>> 1998-to-2001 greenkeys archive:
> http://mailman.qth.net/archive/greenkeys/greenkeys.html
> >>> Randy Guttery's 2001-to-2009 GreenKeys Search Tool:
> http://comcents.com/tty/greenkeyssearch.html
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to n9vmo1 at gmail.com
>


-- 
Joe Montano
N9VMO
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20261012/c7850a13/attachment.html>