(26-06-2017, 02:02)Werk_AG Wrote: If the noise appears to stop when there is a transmission, maybe the source of the noise isn't the transmitter, as it is only powered during the time required to send each data packet.
In any case you are having a remarkable value for the RF Efficiency, I never achieved a value such high (my installation is not in an urban environment too), and I never expected to reach it too, mainly because it I'm using three TX units and some other RF devices, all transmitting to the receiver unit, so some collisions are expected which end in the lost of some data packets, which affect the RF Efficiency math.
It'll be interesting to see what will "fix" it. The band pass filter should take care of any out of band energy coming from the transmitter by at least 50dB, and that's a lot. If the band pass filter doesn't fix it then I will still be more comfortable knowing the TX is safe from the 10,000 watt ERP at 144MHz I send in that exact direction. :-) I've blown up TV's, amplifiers, and even one of my old weather stations with RF.
Eventually the 144MHz antenna will be on the top of that tower so it should be enough in a null for it to not be a problem.