Tag Archives: WSPR

630m WSPR

Cliff, N5CEY, has been listening to 630m WSPR stations over the past few days and has been consistently picking up three or four stations a night with his antenna system. I thought I would try the same using just the mini-whip antenna and the SDRplay receiver. The mini-whip has been fairly decent on the lower bands. I cranked up HDSDR and when I tuned to the WSPR frequency of 474.2 kHz and found a huge amount of inter-modulation products from local broadcast stations. I tried lowering the gain but they didn’t go away. Looks like I will need a low pass filter or an attenuator.

I then switched to using the SDRuno software that goes along with the SDRplay. It has some filtering features that I thought would be useful to try. The waterfall looked a lot quieter with this software for some reason and after piping the output to WSJT-X I was able to decode 630m WSPR spots from three stations overnight. This compares favorable to what N5CEY saw over the same period.

I will be playing with this some more to see if I can further optimize the receive.

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IC-7300 setting to work with WSJT-X (and others)

I prepared a short how-to on setting up and ICOM-7300 with WSJT-X for working digital modes. If you can get this working, other digital software can be easily configured in a similar fashion. The file can be found on the “Projects” page or from this link:

ICOM 7300 Setup with WSJT-X

WSPR Data collected from the 20m Hamstick Vertical Dipole

Here is 24 hours of WSPR data collected from the 20m Vertical Dipole:

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There were 114 unique receive spots and 90 unique heard from spots with 1W transmit. This seems low compared to N5Cey’s 20m 1/4 wave vertical which typically receives 180 to 200 unique spots from his QTH near Los Fresnos.

I did some A vs. B tests on SSB yesterday switching between the 1/4 wave vertical and the vertical dipole. This time I used a remote receiver using Websdr.org. I connected to a station in the San Fransisco area and monitored my voice transmissions. In this case the vertical dipole came in about 1 S units stronger. I then switched to a station in New Jersey and the opposite was true!

I am going to do some additional testing on various 20m vertical configurations using WSPR over the next couple of days.

Completed Linked EFHW

I completed the linked EFHW later yesterday afternoon and tuned the 15m, 17m & 20m bands. I removed about 6″ of wire to tune 15m, 2″ to tune 17m and about 3″ to tune 20m. The antenna is deployed vertically on a SOTAbeams Travel pole up 30 feet. I am using a TV mast tripod as a base. In the field I would lash the mast to a fence post or other similar support.

I tested the antenna on my base rig at 100W and made three easy SSB contacts. Two of these were EU DX contacts. I  left it tuned for 20m and ran WSPR for the last 12 hours. Here is the map:

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This works out to 112 unique heard spots with 66 unique heard by spots when running 1/2W. Looks like the antenna is a winner for Field Day! Only thing I will likely try today is adding a 1:1 choke as I am seeing the SWR swing a bit on SSB transmit.

Some Thoughts On WSPR Data for Antenna Comparisons

I have been keen on using WSPR data to compare the performance of antenna systems. I haven’t worked out a detailed metric but I thought I’d share some thoughts on how the data can be broken down. When looking at 24 hours of WSPR data on a specific band I am seeing the the number of unique stations received is a clear indicator of the antenna’s overall performance and pattern. If this is enough to make the WSPR Challenge board for that period then another clear indicator. As an example, the homebrew Buddipole on 20m (even with resonance being outside the band high) came in at #22 on the WSPR Challenge site with 143 unique stations. I have been hard pressed to make the WSPR Challenge board with the end fed horizontal or the magnetic loop antenna (indoors). So the higher then number the better.

The number of stations hearing me on WSPR is a different story. The ratio of stations heard to stations hearing me is rarely equal. This really depends on the efficiency of the antenna, something that is not evaluated on receive. If I transmit at 1/2W I can expect fewer stations received than if I transmit at say 1W. This will not be a linear increase. What I am seeing is that some antennas have a high count of “heard by” stations for a given power than others. This gives a relative indication of the antenna efficiency. There may be a way to correlate this with a given antenna by testing at different power levels.

 

20m EFHW is Back On The Air!

Lawn maintenance time again and I still haven’t permanently deployed my radials. Took the 40m 1/4 wave down today and picked up the radials.This is a tedious process but not too time consuming. I had the most difficulty in getting the travel mast to retract as it sticks sometimes. Went ahead and setup  and re-tuned the EFHW for 20m as it doesn’t need radials to get hung up in the lawn mower. I am running WSPR as NO5V/1 now to compare against earlier data. I made several USB contacts this afternoon with it. Band conditions were terrible as geomagnetic storms are still raging. The QSB was awful but I did manage to secure a solid 59 into Vancouver.

Next Iteration of the Vertical Antenna – End Fed with Radial Field

I reconfigured the 40m 1/4 wave vertical as and end fed vertical by removing the 1:1 choke balun and installing the 9:1 matchbox as before. One big difference was that I connected the radial field to the ground lug of the matchbox. I have run 24 hours WSPR on 20m with the following results:

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Not bad at all with 132 unique spots thus far (on a fairly bad day of propagation indices). Will try this on other bands soon.

Running 40m 1/4 Wave vertical on 20m

Overall I am very impressed with the 40m performance of the 1/4 wave vertical. For grins I am running 20m WSPR by running through the antenna tuner. The tuner found a match and after only 8 hours had enough unique receives to make the WSPR challenge yesterday. The count is now up to 123 and I expect to be on the board again with a very decent showing. I will continue testing on 17m then over to 80m and 160m. Not expecting much on the low bands but am interested in the results. I am not going to run on 15m because it is resonant on that band as a third harmonic to the 40m primary.  I’ll leave 12m and 10m on the DXxtreme as that antenna has proven itself well on those bands (when they are open).

Update on the 40m 1/4 Wave Vertical

Ran WSPR last night on 40m with the 1/4 wave antenna. Here is the Map as of this morning:

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Started running some JT-65 this morning and while difficult to run pile ups, I am getting QSO’s with JA by calling CQ. On my third one since starting this morning:

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Overall I am very pleased with the performance of this antenna. I’ll be doing some tests on 15m as well although the band has been quiet.

Vertical End Fed Antenna on 40m

The vertical end fed antenna using the 9:1 matchbox and 30 feet of wire has looks like a winner on 40m WSPR. It did not make the WSPR challenge board but has shown a respectable 120 unique contacts and a nice spread of DX stations.The mast has held up nicely with a bit of electrical tape at the joints. Here is the 24-hour WSPR map:

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