Tuesday, October 19, 2010

Isn't QRP amazing?

The Royal Society for the Protection of Birds, a British wildlife conservation charity, has a slogan "aren't birds brilliant!" I think QRPers should start promoting low power operation using the slogan "Isn't QRP amazing!" Because whenever I try using low power the results simply amaze me.

Until starting on my QRSS adventure I had never tried very low power, sometimes called QRPP. I was inspired by Paul PC4T who yesterday wrote about using WSPR on 20m using 50 milliwatts. At the moment I am QRSSing with 50mW on 30m using my magnetic loop, but that still leaves my multiband dipole antenna for some QRPP WSPR experiments.

I connected my QRP power meter to my K3, turned the power control to the lowest setting (0.1W) and sent a Tune signal from the WSPR software. The meter read about 65mW. I thought that I would be lucky to get any reception reports at all at that power level so I was amazed to be spotted by around 20 different stations in the space of a couple of hours, including two from the USA. One, WA8RC, was at a distance of more than 5,800km! To be heard, consistently, over that kind of distance across the Atlantic Ocean using less than 100mW to a dipole zig-zagged into a tiny attic is simply incredible.

I think we all use too much power, myself included. We do it because it makes copy easier or because it increases the chance of someone hearing us calling CQ. Even WSPR users mostly use 5W or more, despite the fact that the "WS" in the name of the mode means "weak signal." Because of our macho desire to have a bigger signal than the other guy we never discover just how far a little power will really go. And that's a discovery that's far more enthralling than receiving yet another 599 report, surely.

Isn't QRP amazing?


PE4BAS, Bas said...

That's a great achievement with QRPP. I never understood why people use 5W or more on WSPR. I always use 1W or less. Actually did more DX with 500mW then with 1W. The problem is that most do not know how to set the audio to reduce their minimum of 5W power output. 73, Bas

Julian said...

Yes of course, having used Elecraft radios for the last 11 years I forget that other radios don't have the feature to adjust the power down to 0.1W in 0.1W steps. Perhaps someone should start a business making RF switched transmit attenuators.