High RF on 2M EME RX line

  • 1
  • Question
  • Updated 1 year ago
  • (Edited)
Need a little direction on this one.  Flex 6700 144Mhz TX RF from XTRV port to DEMI amp to 8877 amp to relay/preamp at antennas to antennas.  RX from antennas to relay/preamp to RX A port on Flex.  RX and TX coax are separate.  Flex shuts down from high RF detected on the RX port.  I am assuming the RX/TX relay at the antenna does not have sufficient isolation to make the Flex happy.  A sequencer is used to keep everything from hot switching and make sure the Preamp does not get a dose of RF.

Are any of the other antenna ports on the Flex 6700 grounded during TX that might be used instead of RX A?
How have others that are using high power 2M EME stations with the Flex 6700 cured this issue?

I have a couple ideas but just want to gain the benefit of those that have already driven this road.

John K3MA
Photo of John - K3MA

John - K3MA

  • 273 Posts
  • 78 Reply Likes

Posted 2 years ago

  • 1
Photo of Jonas Landin

Jonas Landin

  • 1 Post
  • 0 Reply Likes
Hallo John, did you sort this problem out?? 73 de SA7AKE Jonas
Photo of John - K3MA

John - K3MA

  • 273 Posts
  • 78 Reply Likes
Yes.  I had to insert a coax relay to take the RX coax out of the path to the Flex when the radio goes to TX. 
(Edited)