Posted on January 14, 2013
Elsewhere I have blogged my plan to abandon FM as a part 15 vehicle for distributing audio to AM transmitter relays, because of the unsatisfactory nano-pea field strength provided by 15.239. However, while that changeover is engineered we are continuing to seek solutions to an ongoing problem with our FM relay system.
Testing has shown that the signal transmitted from our certified FM transmitter is free of artifacts from the nearby high power stations, but one FM receiver is reproducing artifacts from both full power adjacencies which are clearly heard in the background of our audio as relayed on AM.
We prefer to perfect the existing equipment rather than bear the expense of a more selective FM receiver.
The receiving antenna at this time is simply a random length of wire connected to the antenna terminal at the receiver, and we will be trying more carefully designed antenna methods to reject the unwanted interference from the other stations.
For curiosities sake the antenna variations and results will be shared.
Suggestions are welcome.