3 Mar 2012

160m loft antenna erected

160m loft antenna
Today I erected a small loft antenna for 160m use. The prime purpose is to allow me to test my QRP AM transceiver (that is under construction) with G6ALB in the next village. The idea came from an old RSGB book called, "Practical Antennas For Novices" by John Hayes G3BDQ. It consists of a long coil wound on a PVC pipe about 1.5m long with a couple of wires along the top of the loft as a top capacity hat. In John's design he used 21mm pipe but I chose 32mm instead and my inductance measured 590uH. Just a little more inductance in the shack was enough to make the antenna resonant when tuned against ground (my copper hot water tank and pipes in the house). Now it is time to find out how well (or not) it works. Incidentally without the additional loading in the shack it was a good match on 40m and 15m too.

UPDATE: My first 2 WSPR reports on the new (indoor) antenna were from OZ7IT at 853kms! The antenna must work, HI. Shortly after PA0A spotted me.


David Cope said...

I look forward to seeing how your 160m Antenna works. Topband is a favourite band, so any small loft/garden antennas that work within one's expectations of interest.

73, David, G8JGO.

Bert, PA1B said...

Hello Roger, not bad for an indoor antenna. 73, Bert

Anonymous said...

Hi Roger,

Any idea what efficency of this antenna is like? Do you still have your 20m magnetic loop antenna as a comparison?


Geoff ZL1BLZ

pedro/lu7hz said...

Hi Roger. Can you post some schematic of the antenna? Its kind of hard to get a hand on the book and since some time I am looking for some antenna that can fit in my rather small place. Thanks Pedro LU7HZ

Roger said...

See later post for a diagram Pedro.

Pedro/LU7HZ said...

Thank you very much Roger. Pedro/LU7HZ