Many thanks Dennis.
Hi Roger
I use a Wellbrook Loop type ALA1530 (MW/HF) mounted 1m off the ground and a PA0RDT mini-whip mounted about 7m above ground. Sometimes the loop wins other times the miniwhip. The miniwhip is omnidirectional and uses the e field, whereas the loop is directional and uses the magnetic field. The miniwhip is more open to BC breakthough than the loop but more sensitive. I tend to monitor with the miniwhip, and switch to the loop after homing in on the signal if this helps. BC breakthough is overcome using a simple series LC circuit tuned to the required band at the RX end of the coax. The QRM at my QRT can be horrendous, as I am only 100 yards from the OH
lines on the East Coast main railway line, surrounded by houses and a block of flats with associated busy roads. My 'T' transmitting aerial 8m high is useless for RX. I can fully recommend both miniwhip and Wellbrook Loop, both of which cover from LF to 10m. For best results, I suppose a tuned loop about 1m square has the edge, but not as convenient.
73 Dennis M0JXM
Can anyone advise, from actual use, how well a Wellbrook loop works on 136 and 472kHz RX ? The excellent OIP2 and OIP3 figures and directivity suggest one could be very useful.
73s
Roger G3XBM
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