Welcome to the FlexRadio Community! Please review the new Community Rules and other important new Community information on the Message Board.
Need the latest SmartSDR or 4O3A Genius Product Software?

SmartSDR v3.9.19 and the SmartSDR v3.9.19 Release Notes
SmartSDR v2.12.1 and the SmartSDR v2.12.1 Release Notes

The latest 4O3A Genius Product Software and Firmware
If you are having a problem, please refer to the product documentation or check the Help Center for known solutions.
Need technical support from FlexRadio? It's as simple as Creating a HelpDesk ticket.

receiving antenna signal level tolerance

James Del Principe
James Del Principe Member ✭✭✭
edited April 2020 in FLEX-6000 Signature Series
I have just completed a K9AY loop for receive only on the low bands. While transmitting, I noticed the signal level displayed on the panadapter is bright white to red, indicating a very high signal level into the receive antenna. Of course, this would not happen using only an antenna on input 1 or input 2 which are switched during transmit. My concern is causing damage to my 6500 during transmit. I know there are ESD diodes for surge protection but I don't see that as a solution in this case. Short of creating a switch on the receive antenna coax to short the line during transmit, how do you handle this?  Is anyone else using a receive antenna and how do you deal with this?   Many Thanks, Jim         KD1I

Answers

  • K0FLY
    K0FLY Member ✭✭✭
    edited March 2020
    I have K9AY loops as well as a DXE RX 4 Sq.   I also was  concerned about the signal levels at the RX antenna input.  I use a small 12 Volt relay to disconnect the K9AY loop when in transmit.  The relay (DPDT) is physically located near the FLEX radios and built in a plastic box like found on E-Bay, it  opens the coax center conductor and grounds the RX input when energized.    I use the  TX2 output to key the relay.  

    I also key the +12 to the DXE array to disable the amps at the base of the verticals.

    Gayle k0FLY
  • Bill -VA3WTB
    Bill -VA3WTB Member ✭✭✭
    edited March 2020
    Flex published a chart to help find the best distance the receive antenna should be seperated from the TX ant. In a safe distance considering power out would work.
  • James Del Principe
    James Del Principe Member ✭✭✭
    edited March 2020
    Gayle, I think you are right. I will need to construct a switch box with relay to do just that. Grounding the antenna and perhaps the Receive input should do the trick. Thanks for the reply. Jim
  • James Del Principe
    James Del Principe Member ✭✭✭
    edited March 2020
    Bill, I will look for that chart. I have the receiving loop away from the house but very near my OCFD..... not so good. Long term, I wanted to put a vertical up for 160/80 meters in the front yard, away from the house and other antennas. Thank you for the suggestion.   Jim

Leave a Comment

Rich Text Editor. To edit a paragraph's style, hit tab to get to the paragraph menu. From there you will be able to pick one style. Nothing defaults to paragraph. An inline formatting menu will show up when you select text. Hit tab to get into that menu. Some elements, such as rich link embeds, images, loading indicators, and error messages may get inserted into the editor. You may navigate to these using the arrow keys inside of the editor and delete them with the delete or backspace key.

Comment As ...

Categories