[Moon-net] Wave guide Loss on 10ghz

[Chris Bartram]

Hello Charlie

> ....Just  to  add....considering the low loss of some of the coax cable and
> connectors that are more readily available ( such as LMR600).....the use of
> W/G at 10 GHz  may not necessarily be the BEST way anymore...depending on
> your application, of course....

And, of course, coax doesn't have to be operated in a conventional TEM mode... 
I have a 25m length of LDF4-50 carrying the output of the 10368MHz preamp 
back from the dish to the shack. That has a well defined transmission zero at 
just above 10GHz, where TEM propagation appears to break down. By 10.4GHz, 
the losses (~7dB) are lower than they are at 9.7GHz (~9dB). I assume that 
there is a higher-order mode propagating, but I haven't yet investigated 
further. Trying to do the analysis by making a 3D EM model would take quite a 
lot of time, given the physical structure of the cable, and that of the 
connectors, and I'd really like to spend what little time I have using the 
gear!!

Vy 73

Chris
GW4DGU