02 February 2014

Whispering Over 14.000 Km with 200 mW

It took me a while to get the Ultimate 3 from Hans Summer going. It was of course my fault, for I didn't RTFM.

And I played around with a variable resistor and destroyed settings which Hans had already done. And it was an important setting the wave form coming from the DDS. But with my new scope it was easy to restore this setting and the TRX began to work. But there was another hurdle: It is so tiny and there are a lot of cables coming out of the rig. So I found a used box and shoved everything into it. And the transmitter went into the air.

 The rig has an output of 200 mW into a 7m endfed random wire antenna. And you will not believe me: One of the first stations which heard me

is located in Autralia:

2014-02-01 22:02 DL1SDZ 10.140282 -29 -1 JN48mm 0.2 VK6XT OF86td 14049 102 

A connection to VK6XT who is 14.049 Km away from Tuebingen with 200 mW power output. That are 70.245 Km per watt or 43.648 miles per watt.

Sorry for the bad picture ;-(
Every 10 minutes this beacon sends its message and on this afternoon I have already received over 150 WSPR-reports mostly from Europe. When the transmission is done this little rig changes mode to FSKCW and broadcasts my callsign in CW with a shift of 4 Hz.

So here is again a list of modes you can experiment with:
  • QRSS mode (plain on/off keyed slow CW)
  • FSK/CW mode (frequency shift keyed slow CW)
  • DFCW mode (dual frequency CW)
  • WSPR mode (Weak Signal Propagation Reporter)
  • WSPR-15 experimental WSPR mode with 15-minute frames
  • Slow-Hellschreiber (frequency shifted slow-Hell)
  • Full-speed Hellshreiber
  • Half-speed ("DX") Hellshreiber
  • CW (plain CW)
  • FSK (0-999Hz shift, fast-speed FSK CW)
  • Customisable FSK patterns

And still the best to come: You can do this without switching on your computer. You have those two buttons and make a walk through the menus. Of course the editing is also done in the two button mode:
  1. Left button:   Switch into the menu point
  2. Right button: Choose the letter or number
  3. Left button: Advance to the next letter or menu point.
Sure, it takes some time, but QRSS is slow but audible over long distances.

One problem I still have: There is a GPS-Unit attached to my Ultimate 3. I don't need it, for I can input  time and zone by buttons and the time stability (need for WSPR) is quite good (24 hours or so). But with a GPS-Unit all information about location, time and frequency are present and could be decoded automatically by the TRX. In the moment the GPS-Unit is located on the box. Perhaps I have to extend the cables and place it outside my window.

For the next days I will let the beacon play beacon. My interest is how the propagation from my side, with my antenna is working. Later I will switch bands and will see whats happening.

And I have to reduce my output power: 200 mW is far too much. and I have already a tool for it:

So back to the work bench. There is another project already waiting to be done.

Yesterday I was listening to that concert. Still the best . It's just music and my wife always said turn the volume down, but how can you turn the volume down if you want to hear this kind of music?

Stay Tuned!