NF raises when TX

  • 1
  • Problem
  • Updated 5 years ago
  • Solved
When transmitting on 10M this evening trying to work FT5ZM the entire NF jumps from about -128 dB up to -70 while transmitting with multiple vertical lines throughout the display.
Photo of Greg


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Posted 5 years ago

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Photo of Steve - N5AC

Steve - N5AC, VP Engineering / CTO

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Official Response
With the preamp on you are overloading the receiver.  You can either:

1. Turn off the preamp
2. Listen using a different antenna (RX/TX on different antennas for isolation)
3. Just understand that the signal will overload the receiver when in transmit with the preamp on