WSPR tests My Magnetic Loop Antenna

We had a discussion at our club meeting this morning that got me thinking about how to do some antenna testing using WSPR. Turns out I had the cables needed to control my FT-817ND and run WSPR with my mag loop antenna. I have been underwhelmed by the loops performance on 40m and the design spreadsheet indicates that my efficiency is quite low on that band. This is why I am working on building a larger 40m loop.

I setup the magloop this afternoon and ran WSPR on 40m with 5W out. The only station that could hear me was N5CEY, Cliff just up the road from me in the Los Fresnos area. He could not hear me on the lower power levels. This pretty much confirms that the loop doesn’t do well on 40m.

When I switched to 20m I was being heard all the way up into Canada on 1/2 Watt. This was also pretty consistent. I will try this again tonight and see if the band conditions after dark help this out. Meanwhile I am collecting some interesting data that I can use to compare against the new 40m loop when I have it finished.

This was also the first time I ran digital modes on the FT-817ND and this went pretty smoothly. The rigs programming cable also works for CAT rig control and I was using the original USB sound interface I bought to go along with the FT-450D. No issues except that the receive audio looks to be on the high side.

Update 5/22/2016: I ran the FT-817ND on 5W 40m WSPR from about 5pm through 7am. The results were quite different from what I noticed initially. I had considerably more spots during the night including one from Spain. The receive portion seems to work much better as well as I had numerous spots in Europe:

wspr map

This is consistent with what I would expect from decent band opening on 40m during nighttime hours. This leads me to think that the loop as is would work considerably better than I thought during nighttime conditions.

BTW, did I mention the loop was operating indoors?

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