Hi folks,
Greetings from the Latrobe Valley, Victoria,
Australia.
I hope that this subject is not too far off topic....
For years I have been interested in "ground conduction" communications.
Occasionally I had played with amplifiers and morse code, but when PSK31
arrived, I knew that it was just perfect for ground conduction coms.....
Lately I have hooked up an "earth dipole" which consists of two 100 Mtr
runs of wire with earth stakes at each end. I have been having much fun
listening to Whisters and Tweeks etc (as well as lots of mains hum !).
Today I hooked up my PC to an audio amp and a
suitable transformer and fed PSK31 into my earth dipole.
I left PSK31 sending a large text file and
went for a drive up to the local park about 1 km away and put two earth stakes
in (at 100 m apart) and hooked up my laptop PC using the microphone
input.
Viola!. Perfect copy !!!!!! Really
strong signals too...
There was strong QRN from a nearby electric fence,
as well as overload from Omega, but considering all that, it worked
amazingly well....
One interesting thing is that 1000Hz is completely
clear. I thought that it would have had a 50hz harmonic on it, but not so, it
seems..... of course, PSF31 can tune to find a clearer spot if
necessary...
I was running QRP, perhaps 10W or so. It would be
intersesting to put the full output of my generator into the ground, via a
rectifier and a H bridge and harmonic filter.
I have been collecting info on earth conduction for many years,
so if anyone is interested in this facinating subject, please write direct
to me at
[email protected]
73's .................. Zim (Graeme
Zimmer) ................... VK3GJZ
