Wednesday, November 04, 2009

PSK31 signals received on 40m

I left the K3 and Fldigi spotting signals on the 40m band last night. The antenna was the MFJ magnetic loop in the attic. The screengrab below shows the results.


No transatlantic signals were heard, but a couple of signals from Siberia, east of Novosibirsk, in the hour or so after midnight, were nice to see.

I'll repeat the exercise soon using the dipole.

12 comments:

Paul said...

Hello Julian, I had the same plan for last night, but we had thunderstorms and I was afraid for lightning and damage to the rig. Since yesterday I received 33 countries with PSK31. I did hear some stations from North America this afternoon, but not yet reported. 73, Paul PC4T

Jorge Luis - ki4SGU said...

Julian; Thanks for the plot - I've been curious about those MFJ Loops for years, and I have read your previous posts and reviews (twice), but your plot from last night's activity speaks volumes all by itself.

Now, if you and Paul are going to retry your experiment, I'd like to tagged along. I know I will be busy tonight (no time for real hands on radio play), so that means I could setup the radio in RX beacon mode (reverse beacon?) - we would then have a UK & USA plot to compare, admire and learn from. ?? /73 de Jorge Luis /ki4SGU

g4ilo said...

Hi Jorge. I think I'll be WSPRing on 40m this evening as it is a 40m WSPR activity night and there are more than the usual number of stations on the band at the moment.

Jorge Luis - ki4SGU said...

OK, I'm a few hours behind you guys, but I'll fire it up on 40m and let it run, leaving the office now.

Jorge Luis - ki4SGU said...

OK, I'm on the air on the WSPR board, WSPR and the ether are all working great. After just one hour on the radio, I have several contacts near the UK & EU, so in at least theory it should work. -Jorge Luis /ki4SGU

g4ilo said...

And indeed it did.

091105 0308 4 -28 1.0 7.040079 KI4SGU EM73 43 0 12677 20

One single spot, right at the limit of readability. It obviously wouldn't have happened if you weren't running 20W. My 2W were not received outside of Europe.

Jorge Luis - ki4SGU said...

Interesting!? I wonder how low we can go? and I'm curious to see how Paul /PC4T did on our little experiment. I'd like to try 30m or 15m sometime next week, So please let me what day would best for you (and others). -- Also for this test I did not get home until well after dark, missing the grey line. If there is a next time, I'd like to fire up the station before I leave for work and let it run during the day and into my evening to see the effects with the grey line, and maybe at higher/lower power(s) to see that makes any differences. Julian, With your fancy k2/k3's could you change the power on the quarter hour? (or hourly) I know you have that snazzy program control business, my old Kenwoods have no such modern accouterments. Thanks again Julian - WSPR can be "intellectually" fun. Jorge Luis /ki4SGU

g4ilo said...

15m will be the activity band during the day on Wed Nov 11th, so that would be the best time to try 15m. 30m is always busy any day, but less on Wednesdays as those who can switch to the activity bands.

Although the K3 supports CAT control, the WSPR software doesn't, so changing the power on some kind of schedule isn't posibble.

Paul said...

Hello Julian and Jorge, I like this kind of experiments. I will run WSPR tonight on 40 meter starting 20.00 hour UTC. Next week we could try 30 meter as well. 73 Paul PC4T

Jorge Luis - ki4SGU said...

Gosh - I almost missed this, I was just packing for the evening.

Paul - OK FB on 40m tonight I'll fire my station as soon as I get home. - Thanks (WSPR is great for family guys, like me. I'll be out exploring the ionosphere tonight while simultaneously having dinner and a tele movie with the wife and kids)

& Julian FB on the PC control, I was afraid of that. But I know you (from your blog) to be very clever, and perhaps find a way around it, or at the very least get folks thinking about it.

11NOV @15M - it is a date.

As for the direct QSO business - I will download the JT65 software tonight and see what it takes to run it. k1JT also has something called SimJT which seems be interesting and towards the issue of "once WSPR has blazed the path, can real HAMs follow with CW?"

An Ppen Question: At what SNR do you believe a "normal" QSO is possible? For Olivia? PSK31? CW? -- I Googled this earlier today, and there seems to be some buzz about SNR numbers -- SNR@1000 vs SNR@2500 (WSPR-style). Your thoughts on this would be most helpful baseline to test against.

PS: This weekend there is a fairly large HAMFEST (Rally) here in Atlanta. I'm going to look for one of those MFJ loops cheap, most QRO folks don't seem to appreciate the intricacies of that fine devices as proved by you.

Jorge Luis - ki4SGU said...

It seems you already answered the issue best SNR to qso ... http://www.mail-archive.com/elecraft@mailman.qth.net/msg70283.html

nice job Julian!

Jorge Luis - ki4SGU said...

Wow this post are getting long.. I let my station run last at 50w for an hour, then 10w, then finally receive only (it is still monitoring the ether) -- I looked for you or Paul but did not see either. I also constructed my own files to hear what negative SNR really sounds like. Please give a listen and comment. -- http://ki4sgu.blogspot.com/2009/11/signal-to-noise-ratio-raindows-in-dark.html