1,164,000,000 MILES PER WATT TEST

 The start of this test to see if Bill W4HBK and I could get my QRSS Signal from Las Cruces, New Mexico to Pensacola Florida, a distance of 1,164 miles at a power level of 1 microwatt. We started in November of 2013. We started the test at about 100uW on 30M with this test setup. It is a Hans Sommers Ultimate, some attenuators, and my M cubed Power Meter/Frequency Counter.

This setup worked pretty well until the middle of December the variations in temperature in my garage shop was causing the frequency and the 10 minute repeat timing to vary. To counteract the temperature changes, I built a foam cocoon for the transmitter to live in. This worked for a while longer but it wasn't tight enough or thick enough to provide a stable temperature vessel. Here is a picture of this configuration.

Along about the middle of February, I acquired a Hans Sommers Ultimate 2 from my friend NM7J and built it up with its 9850 DDS Oscillator and set it up to run on the 30M frequency with the 10 minute interval and using my Trimble GPS 1 PPS to stabilize it. It automatically calibrated the unit and from then on my frequency and transmitting timing were spot on. By this time we were getting down into the 25uW and lower ranges but the propagation was really being ustable with lots of solar flares and no signals were getting between us. I made a new cabinet for my new transmitter out of a $2 cardfile cardboard box, alumimum tape, and some presentation foam board. I also found a Omaha Steaks shipping container that was a much better thermal container than my pink cocoon. The final transmitter configuration is shown here.

 The lowest we could get on 30M was 15uW on 3/3/2014. Try as we might we just couldn't get a lower signal level. The noise, QRM from WSJT JT65A and being clobbered by Over the Horizon Radar signals made the task very difficult. Plus, we were running out of time as the spring storms and summer noise was about to pickup at W4HBK's site in Pensacola. Here is the stack of the 15uW 30M signal that we were working with: (The thing that makes me most proud of this screenshot is the pencil thin lines of my signal - this means that the frequency was ROCK stable and the 10 minute repeat cycle was very exact. I think that this is a stack of 22 separate images. Even though the signal was weak, it was still very distinct.)

 Because of the 30M QRM problems and being stuck and not being able to copy anything lower than 15uW, Bill W4HBK suggested that we move to 20M to see if it was any better. The frequency is a lot clearer and there wasn't any WSJT JT65A traffic. Plus, I have a 3 element beam that could be used to boost the signal some 8dB. So, we went to 20M and reset the test transmitter to 23uW to see if it could be copied. In quick sucession we went from 23uW on 4/24/2014 to 3.12uW on 5/5/2014. Its screen shot is below.

Now is it really getting tough. The noise at W4HBK's Pensacola location is really starting to become a problem even on 20M and we still had one more 3dB step to go. The space weather was being active with a number of sunspots spitting out numerous C and M class flares and the A index was above the 7 mark for most of the time. Every once in a while there would be what Bill refered to as Magic Propagation. My 1uW signal would come out of the noise for a 1 or 2 minute period and you could see it without any aids. Unfortunately, These periods were not long enough for my whole call sign which takes about 7 and one half minutes to complete. So we needed a good quality, long period where my signal was visible on W4HBK's 6 Hour grabber display so he could pick the time periods he wanted to use to stack to bring my signals out of the noise. This event happened on 5/17/2014. My signal was visible on the 6 hour display for over 3 and 1/2 hours and Bill was able to gather up enough 10 minute segments to stack to bring the signal up out of the noise. Here is the 6 Hour display from 5/17.2014:

Here is the stacked image of those 10 minute screenshots and what we worked so hard for 6 months to get:

The above screenshot is the result of 6 months of work generating the signal and copying it over a 1,164 mile path between my house in Las Cruces, New Mexico and W4HBK's house in Gulf Breeze, Florida. We did it through wind storms, hail storms, Bill went through multiple tornados and a flood. Cold nights, Antenna repairs when Bill's racoons decided that they needed to rewire his antennas. Battling the swamp, posionous snakes, hot sun, Equipment failures, unpredictable propagation, Massive QRM from Over the Horizon RADAR, a Lightning Strike on Bills Station. Just about everything that can happen ... DID. But through all of that, We still accomplished what we both thought of as impossible... 1,164,000,000 Miles per WATT. Using a measured .000001 Watt signal to the antenna. We have applied and are waiting for our QRSS certificates from the QRP ARCI. It is an amazing accomplishment that I am still trying to get my brain around. THANKS BILL W4HBK FOR A FANTASTIC RIDE.



 A picture of W4HBK's Shack needs to be included to give you a complete picture of the whole test setup. We both are just using standard Amateur Radio equipment that has been modified for the stability and frequency control to do these type of experiments. Below is a picture of Bill's shack:

The litte vertical box with the yellow LED is Bill's temperature control unit for the Master Oscillator of his Kenwood TS-440S. He has that receiver stable to within 1 Hz. The information on his Temperature control system for this transceiver can be viewed at his blog. His DDS controled Manned Experimental Propagation Transmitter is the unit just above the Heathkit HW-8. The screen is displaying the Spectrum Lab program by Wolf Buescher DL4YHF and his excellent tips for using this program can be viewed on his blog.

The picture below shows Bill's very excellent antenna farm that he uses for his excellent PENSACOLA SNAPPER GRABBER. With these antennas and a Antenna Tuner, He covers all bands and has copied many weak QRSS and WSPR signals from all over the world. It is really amazing how very well this antenna system works.

Bill's Blog site is a wealth of technical information for most operations associated with QRSS. He has excelled in his study of this very weak signal mode and the physical effects that are seen on the air. He is always willing to help the newcomer and the old timer. His Grabber THE PENSACOLA SNAPPER is always on the air giving us all a known site to check our
transmissions. You can visit his BLOG site HERE. You can find his PENSACOLA SNAPPER GRABBER at this SITE.

For Bill's Version of our "Adventure" check out his blog site HERE


 The 1,000 Mile Per Watt Certificate for a
1.164 Billion Miles

Well, Above is the 1,164,000,000 Miles per Watt certificate issued by the QRP Amateur Radio Club International after submission of our data from the 1uW one-way contact between W4HBK and myself. It is a mind boggling accomplishment to me as I really didn't think that it was possible. But I don't think this is the end. As more Amateur Radio Operators become interested in QRSS and the advancing technology of Spectrum Analyzers and Receiving Techniques. This accomplishment will be eclipsed hopefully many times. As long as there are inquisitive minds who wonder if it can really be done, There will always be those trying to do it. So, Bill and I have shown it can be done at this RF power level. Who is going to be next to better it?

73 Dave WA5DJJ

 Local Newspaper Article of the Contact

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