4m Wspr May 2010

[G0MJI]

I am running Wspr on 70.0286 mhz most evenings throughout this month from IO83. 20 watts into a half-wave vertical. No spots so far...

Bri
G0MJI

[M5TXJ]

Will do similar when around, (I work shifts) 70.0286 +/- 2W 5ele beaming 195deg. 33% TX
73 Dave 'TXJ

[G0MJI]

Hi Dave.

I'm in the North-West and vertically polarised, well the antenna is not too sure about me.

I'll run it this evening, still no spots in a fortnite, I'll keep at it.

Bri G0MJI

[G0MJI]

Hi Dave.

Now running horizontal omnidirectional. Will be on air most of this week by day until 9pm local.

Bri

[G0NMY]

Did you guys ever hear each other with wspr?

[G0MJI]

Yes when conditions were up contacts were made across the UK. Very similar to 6m Wspr really though perhaps less affected by AS. The difficlut part is getting stations to try as the Wspr site doesn't have a 4m filter on the map so you have to make a sked in the old fashioned way. You can check 4m spots using the 'Old Database' filter, but of course you need someone to spot you and they won't know you are there unless you arrange it yourself. I made some new friends this way though and it was a good laugh too.

I don't have my antenna up anymore, currently focusing on 60m Wspr. I can fling a vertical up at short notice if you ever want to try, though best results were achieved with horizontal yagis as might be expected. No one as far as I could tell tried beyond UK borders, but there's no reason to believe it wouldn't also be comparable with 6m, where regular spots over thousands of miles are made with very simple antennas, conditions are everything of course.

73

Bri
G0MJI

[G0NMY]

yeah I noticed that aswell about the wspr reporting database they list the 4mtr freq but they appear not to filter or show any stations.
I left mine running overnight but never heard anything, maybe I am better of trying the faster Meteor Scatter modes.
I have just got a G4NNS transverter working at 4w into a dipole in the loft
so maybe Im not running enough uuumph for the band.

Time will tell.

[G0MJI]

Most likely there is no one to spot you. I ran for many weeks until a few stations appeared. I had to contact them via email/forum/Wspr chat first. I am away this weekend but would be quite happy to TX/RX next week any evening. Just let me know and I'll put a vertical antenna up. It'd only take me an hour or so...

[GM4FVM]

Some very interesting traces on 4m WSPR.

With G0MJI especially I can see the Doppler effect very clearly. Presumably this is due to aircraft reflection. As well as the main trace, often strong and with no drift (WSPR reports even slight drift, say 1hz), there are other traces on the waterfall.

Generally the Doppler is tilted down at about 30 degrees, or up to 45 degrees sometimes. Thus, reading the waterfall scale, the shift is about 20 to 30hz, depending on the severity of the effect. They always slope down left to right which suggests to me that the aircraft (?) are only moving away from me (or the universe is expanding more than I thought). No doubt some simpler explanation can be found for this as G0MJIs traces of my signal look similar.

Sometimes the Doppler line starts at a higher frequency than the main signal, and crosses its path in the form of an X.

At other times, only the Doppler lines appear, with no or very weak direct signal (which does suggest aircraft reflection).

I have seen similar results from signals coming from the South, but not so much on traces seen from GM, GW or PA.

As the WSPR waterfall is only 200hz wide, it is easy to see the effects. You can also see who has a stable rig/transverter, and thankfully G0MJI is perfectly stable.

If you are going on to 4m WSPR, it is a good idea to let people know via the WSPRnet chat page. Other bands have a map entry, but not 70MHz, yet. The frequency in general use is now 70.091 (dial).

Jim
GM4FVM