Re: Re elevation on a dish
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Hi Dave ,
I had a 20W TWT based system up this mast for over 20 years before moving on to use bits of it for 10GHz EME at G4RFR .
The first G to G contact on 10GHz (CW) used the TVTR - 1994 between G4RFR and G3WDG , using 12 Ft prime focus 0.43f/D dish at our end.
The TVTR was quite a load for my 30Ft Western Ulimast and restricted other band antenna deployment a bit .....feeding all TWT rails up rotator style multicore cables ......
My TVTR used original G3WDG modules with a modified 4 port WG16 on its front end , with the 2 stages of LNA directly on the RX port and TWT output on the TX port .The feed was a G3PHO type WG 16 flanged and feeding the 4 port switch via EW90 elliptical waveguide .Probably had about 1 m total between the feed and the front end LNA .
For tropo use this still represents a reasonable insertion loss . You can easily make ur own EW90 flanges to marry standard WG16 flanged ports .
Form the required bends into the EW90 - using gentle bends by hand /vice.
A 10W system at the dish will form a potent terrestrial system , but do spend the time to Engineer the housing to prevent condensation .An inverted bucket format is good as it allows airflow and if you take all services in via the open end rain tends to stay out .( worked a few with 10W TWT last year on the 12Ft dish - on 10GHz CW ) . The 200W TWT makes for louder echoes though .
From home I am only operational on RX on 10GHz , but having £10 LNBs and GPS reference locking makes it a potent and cheap thing to do .