Radio number 2 has limited range

Discussion in 'Avionics and Upgrades' started by jd21476, Nov 4, 2022.

  1. jd21476

    jd21476 Line Up and Wait

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    jd21476
    I have a GNC355 for a COM/NAV radio #1 and a Narco 850+ as a COM2. Both are linked to a new PS Engineering 450b audio panel. When the GNC355 was installed i was having an uissue where it would drop the GPs signal if I keyed the mic on a channel between 120.6 and 121.7. After taking it to an avionics shop they swapped the antennas and found that it fixed the issue with my GPS dropping the signal.

    The problem now is that my COM2, which I like to primarily use for ATIS and used to be able to pick up from 30 or more miles out on a clear day, can barely pick up a frequency while sitting on the ground at the airport. The range is probably down to a 1/4 mile.

    I dont want to take it back to the shop if its an easy fix. Is there a way to diagnose the issue and boost the signal?
     
  2. mandm

    mandm Cleared for Takeoff PoA Supporter

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    Michael
    Sometimes my radio would act up depending upon the weather and if it was behind some big metal hangar on the ground, either move locations or swap coms solved it. Unsure if static wicks could help with that either? Definitely I can get ATIS en route up to a considerable distance on both coms but I know my com on my GPS works much better than the other com.
     
  3. asicer

    asicer Final Approach

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    As a quick check, can you look inside for bulging and/or leaking capacitors?

    [​IMG]

    [​IMG]
     
  4. Daleandee

    Daleandee En-Route

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    I would start right there. I suspect it's an antenna, connector, or coax problem ...
     
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  5. FORANE

    FORANE En-Route

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    Yeah, that ^^^

    If you know anyone with an SWR meter, I would place it between the comm 2 and its RG400 cable and check the SWR. Suspect it is very high. Suspect that comm 2 RG400 cable has internal failure or there may be corrosion at the comm 2 antenna.
     
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