BATC Forum

I have tried google, but not got a definitive answer....
I have a rectangular LNB for 3.4GHz, allegedly destined for a cruise ship. It works fine, but has only a single probe and therefore no option to change polarity. Tests across the shack with a very throttled back Pluto and a small vertical antenna have not convinced me completely, but i THINK if I want to receive a horizontal signal, the WG should be mounted with the wider dimension VERTICAL, which would place the probe inside horizontal.
I'm going on the roof tomorrow (too cold today) and hope to fit it there for GB3JV reception.
Advice from the hive please...
Gareth

Hi Gareth

Yes, C-band LNBs are usually single polarity with any polarity mangling usually taking place in the feed.

The waveguide should be mounted in "portrait" mode for horizontal polarisation. Think of the feed probe as part of a dipole and then it all makes sense.

Be careful on the roof!

Dave

Thanks Dave, yes, that makes sense and matches with the experiments in the shack.
I always hold on with all 4 limbs.....never fun the first journey to the ridge but actually easy and safe-ish access as far as roof ladders go....
Gareth