Mobile on 136kHz!!!

(well almost)

It can be done! All I have to do now is get the thing solid enough to operate on the move. With the setup shown "static mobile" in the Worcestershire countryside I have worked GW4ALG in Chepstow (102km), G4HYU in Louth (166km), G0UPU in Cheltenham and G3YMC in Bracknell. I have also had a good report from G3KEV in Scarborough (237km).

The amber coil is a huge 23mH job which, even with the 12ft tank-whip on top wasn't quite enough to resonate on 136kHz. I had to add some horizontal(ish) rods just above the coil and a bit of extra inductance in the form of my /P loading coil and variometer seen on the roof. The portable TX was used and, with about 300W of RF I was able to get almost 1A of aerial current with only the car body for earth. I have since used a longer top section of 15ft and it then loads OK without the extra coils. All I have to do now is reduce the height to 14ft overall and we're really mobile........

I'm not the only one nuts enough to try this, G3XTZ has also operated /M using a vacuum variable C inside the car connected to a top wire attached to his whip. So far only a few miles range but I'm sure the system is capable of more. We must try a mobile to mobile QSO...

Interested in HF mobile operation? More info here..