[MLB-WIRELESS] Success with GHO

[Peter Berrett]

Hi all

I have modified the 24db Galaxy dish I purchased off Peter B. and 
created a new dipole to drive the antenna. I compared it to my cantenna 
(estimated gain 12 db) and there is definently an improvement of 8-10 db 
over the cantenna.

One interesting discovery was the polarisation of the feed.  The 
reflector is like a series of copper pieces each about 1.5 cm wide with 
a similarly sized gap between each. These gaps are quite long (>10 cm). 
Initially I polarised the feed perpendicular to the copper strips  but 
the results were disappointing. When however I polarised the feed 
parrallel to the strips the results were significantly improved. Thsi 
seems counter-intuitive to me.  I suspect that if I was to put some 
aluminium fly screen over the gaps berween the strips I would get even 
more gain. Because the gaps exceed 1/10 of a wavelength it probably is 
not a perfect faraday cage.

I had no problem logging in to GHO although I noted that several nodes I 
had bookmarked on my laptop were unavailable.  This may be due to the 
cloud that has been hanging around Mt Dandenong affecting some of the 
links?

I shall try and see if I can get through to FUT today with the Galaxy 
Antenna from my location (JXG) . It would be tempting to go up to Mr 
Dandenong and see what kind of range one can get with an antenna like this.

cheers Peter