Too much RF?

Discussion in 'General Technical Questions and Answers' started by K1ZNE, Jun 28, 2020.

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  1. K1ZNE

    K1ZNE Ham Member QRZ Page

    I've been struggling with my lack of conditions for a proper antenna and the most I've been able to install is a 53' end fed with a 1:9 unun. I get very low swr from 80 to 10 m but the few reports I've got have been "too much RF, can't understand your call sign". Can anyone pls tell me how to fix this? Thank you!
     
  2. WN1MB

    WN1MB XML Subscriber QRZ Page

    "...lack of conditions for..." - Care to translate that to English? I assume you mean lack of sufficient real estate.

    "too much RF..." - I can only assume that meant you operate phone and RF is getting into your audio. More information, please.
     
    WQ4G and K0UO like this.
  3. K1ZNE

    K1ZNE Ham Member QRZ Page

    Yes, real estate is what I meant, then neighbors too close, electric lines, trees.

    I am only operating phone so far. They have mentioned "too much RF', I assume they are receiving my signal very distorted or noisy and they are unable to understand my call sign.
     
  4. N8VIL

    N8VIL Ham Member QRZ Page

    What is you setup? Radio - amplifier - tuner - feedline?? Proximity of your antenna to your shack.
     
  5. K1ZNE

    K1ZNE Ham Member QRZ Page

    My setup is an Icom iC-735 with the pS-55 and the AT-150 antenna tuner. Feedline is 50' of RG8U from my shack to the feedpoint of the balun, from there 53' 18 gauge wire to the top of a 25' high flag pole. I also have a MFJ artificial ground tuner, with around 50' of wire on the floor of my shack. No amplifier.

    Thanks.
     
  6. N8VIL

    N8VIL Ham Member QRZ Page

    I would first try a proper ground bonded to your electrical service ground. Your artificial ground may be acting as the other half of the antenna and radiating RF into your shack getting into your audio. Common mode current on your coax shield.
     
    Last edited: Jun 28, 2020
    WQ4G, K0UO, N0TZU and 1 other person like this.
  7. K7TRF

    K7TRF Premium Subscriber QRZ Page

    You could have RFI on your audio in which case things like choking your feed line before it enters the shack and or better coax grounding may help. But you could also have basic overdriven audio. How does the ALC meter on your rig react when you speak into the microphone. Also if you have speech processing engaged you may need to back off the amount of processing as that's a very easy way to end up with distorted audio. But if the ALC meter readings only reach up to the top of the ALC range on the loudest voice peaks and you're not running speech processing then I'd look into RFI issues.
     
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  8. W7FOX

    W7FOX Ham Member QRZ Page

    Your counterpoise may be radiating more than your antenna, guaranteeing RF in the shack syndrome. Try to get it out and away from the shack.
    Unbalanced antennas like end fed and off center fed are going to encourage RF in the shack and cause problems. I am a firm believer in balanced antennas, and would suggest going with a dipole fed with balanced line, like open wire or twinlead. A good transmatch will get you all bands at acceptable efficiency, depending on how long you can make your dipole. Good luck.
     
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  9. KM3F

    KM3F Ham Member QRZ Page

    Is the Fag pole Metal?
    Is your wire spaced out from the Flag pole very far?
    Get that coil of wire out of the radio area..
    What made you think it had no RF on it? It doesn't just lay their with no purpose.
    An CW SWR check is not the same as a voice signal. It cannot give you any indication of RFI even if the match is perfect.
    Good luck.
     
  10. K1ZNE

    K1ZNE Ham Member QRZ Page

    I will try to eliminate the MFJ Artificial Ground and its wire inside the shack but I can't install a counterpoise outside. Yes, flag pole is aluminum but wire is attached to an insulator, 6' from it. I was thinking that a vertical antenna would work for me due to the restrictions I have but then I've been told here in the group that a vertical antenna without radials is about the same as a dummy load. Thanks to all for your responses!
     

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