23 Jan 2018

136kHz WSPR RX

Even with my unbelievably poor system, I managed to spot 4 unique stations on 136kHz WSPR RX in the last day. WSPR is a wonderful mode.

Next season I really must try a miniwhip on 136kHz and 472kHz RX.

Many years ago I received 136kHz QRSS3 (sent from home) on a miniwhip mag-mounted on my car. Despite the very low ERP, it was clearly copied the far side of Cambridge (20km?) and I stopped. Much further would have been possible.  I am pretty sure this was using my earth-electrode "antenna" in the ground as the TX antenna. As far as I am aware, I used this E-field probe on RX on the car roof. This fed the deaf (at 137kHz) FT817.

2 comments:

Pedro-CT7ARQ said...

I am going to build your project ang give a try !!!
Does a ferrite antenna will performe reasonable?

73 de Pedro Almeida CT8ABY-CT7ABY

Roger G3XBM said...

Hi Pedro, the miniwhip is a very effective RX only antenna at LF and MF, although it needs to placed so noise pick-up from the house is minimised. Usually, this means putting it as far away as you can from houses and ground the miniwhip (E-field probe) at the bottom of its mast. Mount it as "in the clear" as much as possible. Some add ferrite beads on the coax near the miniwhip to minimise noise pick-up on the cable.

I have never tried a ferrite rod antenna (RX or TX) on 136 or 472kHz.

Roger G3XBM