[NLRS] Beacon Question and a Modest Proposal

[aflowers at frontiernet.net]

Bill,

I'm just going to chip in my two cents to what Doug said.

The modulation methods in PSK31 and WSPR won't be of much use for aurora propagation on VHF.  From EN07 that might matter quite a bit. 

PSK31 is often destroyed on VHF scatter paths do to the phase modulation that often accompanies it (the buzzsaw sound we sometimes hear).  Longer propagation (e.g., ducting, Es) that might be of more interest to us has less of an issue with phase distortion.

CW Skimmer does a pretty good job of copying a CW beacon, and if you want automated reporting, have a look at the reverse beacon network filtered for 6m.  It probably does pretty well, but I haven't paid that much attention to it.  It looks like the Europeans have several reporting stations, or at least they are the ones with propagation lately.  Right now you can see all that great TE propagation from exciting places like D44 and V51 to southern europe--most of which is beacon spots.

http://reversebeacon.net/dxsd1/dxsd1.php?f=13

K0AWU can tell you all about SDRs if you want to set up your own receiver...

Cheers,
Andy K0SM/2



----- Original Message -----
From: "Doug Reed" <n0nas at amsat.org>
To: "NLRS List" <nlrs at mailman.qth.net>
Sent: Friday, September 23, 2011 2:47:49 PM
Subject: Re: [NLRS] Beacon Question and a Modest Proposal



Hi Bill.

Interesting issue about the beacon frequency restriction.... Maybe that 
is only for CW beacons? I know that <http://propnet.org/> has been doing 
automated PSK31 propagation beacons on most bands. On 6M they are up at 
50.291MHz. I had a PropNET 6M packet beacon station on the air before that.

As for the beacon mode, I'd say stay with CW if you want something that 
anyone sitting at the radio can tune in and use. But if you want 
something that will be an automated propagation beacon, then choose 
either WSPRnet or PropNET. Both systems are digital beacons that listen 
for other stations as well as transmit your beacon several times an 
hour. Both systems report back to a central Internet site saying what 
they heard and anyone can access the results on a real-time map from 
their web site. So far both systems are independent and don't share 
their info.

Personally, I like the glitz and eye candy of the WSPRnet web page but I 
prefer the PSK31 mode used by PropNET. The main reason for my choice of 
PropNET over WSPRnet is that WPRSnet can decode signals about 24dB below 
the noise floor while PSK31 can dig down about 17dB below the noise. 
Since I want my propagation beacon to be useful to people running 50-100 
watts of SSB, I need to limit the beacon power according to those 
figures. That means my PSK31 beacon should be 1 watt or less, a WSPRnet 
beacon should be UNDER 100mw......

In similar fashion, I'd suggest a 6M CW beacon should be under 25 watts. 
If it is heard reasonably well, that would indicate that a SSB QSO could 
probably be made with 25-50 watts or more.

Back when I had the PropNET FM packet beacon station on the air, I think 
I was running 25 watts from the radio. My reasoning is that FM needs a 
fairly strong signal in the .5 to 1uv range to decode a packet message. 
So if my 25W packet beacon was received, I know that a SSB QSO should be 
possible with a similar power level. But PropNET doesn't use FM packet 
beacons any more....

So if you want a beacon that anyone can tune around a radio and hear, 
stay with CW. But if you want a beacon that anyone can check on the 
Internet, choose PropNET or WSPRnet. So far there are not a lot of 
people using 6M with either system. Most PropNET and WSPRnet activity is 
on 10M or 30M. WSPRnet has a better international following, 
particularly on 30M. They may be about equal on 10M.

Those are my opinions regarding beacons. Probably the biggest thing I 
have against either system is the need to dedicate a fairly fast 
computer and a decent sound card to either mode. And the need to use a 
SSB radio. A CW beacon transmitter can be a lot simpler and could be 
built from an old commercial FM radio if you wanted to.... Although 
you'd probably want use a crystal oven or replace the crystal with a 
more stable oscillator.

Good luck with the project!

73, Doug Reed, N0NAS.

Bill Ockert wrote:
> I have been considering a 6m beacon for EN07 for some time but rather than
> sticking with the
> traditional CW beacon I was thinking of an updated one.  With the technology
> that the WSJT
> protocols made available and the  margin that those protocols provides there
> are likely potential
>   openings that are being missed.
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