A friend of mine : F5RZJ was QRV as SO/SB 10m during the last WPX test.
He has noticed that he was answering second harmonics signals on 10m and so,
he got no reply from these stations calling on 14MHz.
The stations where HA, S5, 9A, the skip was Es.
What about harmonics of our transmitters (30dB ,less or more)?
How to measure without any expensive spectrum analyzer?
We are very surprised to see that M/M stations may generate such harmonics
levels. What about theyr own receivers?
Do many contester use pi-L networks in the amplifiers or do they use low Q
pi networks because it's easier to build?
With CW receivers the problem is easy to fix, but with SSB modulation the
QRM generated by such drawback is more difficult to identify, the modulation
is no more readible and the modulation becomes a wide band signal. Isn'it
what we call splatters and do we always identify the faulty station or do we
choose the nearest station of our QRG to complain?
73 de F6HLC
Christian
--
CQ-Contest on WWW: http://lists.contesting.com/_cq-contest/
Administrative requests: cq-contest-REQUEST@contesting.com
|