[UK-CONTEST] Pre Amps

[David G3YYD]

Above 10m, I only work 2m. I turned the 2m beam (single 19ft boom Yagi 
at 65ft AGL) for minimum noise and then replaced the antenna coax input 
to the transverter with a dummy load. The noise dropped by 12dB. QED a 
pre-amp is pointless. The transverter noise factor is <1dB and the W103 
coax loss is only 1.1dB from the antenna. Using LDF4-50 would reduce 
that by circa 0.3dB - not worth the effort or the cost.

The need for a mast head pre-amp is mostly due to poor NF on commercial 
transceivers. Pity about the adverse impact on receiver dynamic range, 
but if you live far from the crowded areas of the country then does not 
matter so much. The mast head pre-amp is a fault liability that takes a 
lot of effort to fix so best avoided if possible.

David G3YYD

PS in a contest I always give 59(9) as it makes life so much easier by 
reducing operator work load at both ends. It is a contest not a 
technical study.