static on radio

Discussion in 'Instruments / Avionics / Electrical System' started by Bwing96, Jan 21, 2008.

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  1. Jan 21, 2008 #1

    Bwing96

    Bwing96

    Bwing96

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    I have a Sporty's SP-200 Nav-Com handheld using AA batteries witha Av-Comm 400 series headset and I am getting static noise from the engine as it increases with an increase in throttle. I have only taxied around @ 12-1500 rpm and had to turn it off it was so annoying. I aslo do not have an electrical system on the plane.

    Which is the culprit, the headset or the radio ? And what can be done to eliminate the noise.
     
  2. Jan 21, 2008 #2

    wally

    wally

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    The problem is most likely with the airplane ignition system. Is it a production type of aircraft engine like Lycoming or Contental?

    If the "P" lead(s) from the magneto(s) is not a shielded wire and well grounded to the airframe, it will cause a bunch or electrical noise. Is it a composite airplane?

    Is there a possibility of borrowing another hand-held radio to try? I found the same problem as you as well as another problem with my Icom IC-2. The correct headset adapter was not compatable with one of my headsets but would work with another headset. The Red Barron headset would continuously key the transmit when I plugged the microphone in.

    I have a Lycoming powered plane that has engine noise in my hand-held radio. I haven't fixed it yet. It has no electrical system either. I think I need some more shielding over all the few wires going to or near the cockpit! Starter wire, electric fuel boost pump, and 2 shielded(!) P leads.

    Best wishes,
    Wally
     
    Last edited: Jan 21, 2008
  3. Jan 21, 2008 #3

    Dana

    Dana

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    When I first tried my Icom A24 handheld in my Kolb (Cuyuna engine) it was unusable. Switching to resistor spark plugs almost completely eliminated the noise.

    Years ago (1980's) I borrowed an early handheld to try in my Taylorcraft (A-65, also unshielded ignition) and it too was unusable. Never pursued that one as I couldn't afford to buy a radio of my own, and didn't really need one anyway.

    -Dana

    Sex in a Volkswagen = Farfergnookie.
     
  4. Jan 21, 2008 #4

    9aplus

    9aplus

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    You may need to block ignition like in all ordinary cars,
    resistors, shielded cables and block capacitors on all
    open spark sources.
    Closed loop external antenna may help too, also improve reception
    in case of near lightning storms, AM modulation is quite sensitive
    on all kind of near discharge, FM is much better but not standard
    in aviation.
     
    Last edited: Jan 21, 2008
  5. Jan 22, 2008 #5

    Bwing96

    Bwing96

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    It is a C-85. A friend flew it 3 weeks ago with an Icom-A4 and said there was a little noise but was had no problems hearing or understanding others. The radio is hooked up to an external antennae that is mounted on top of the cockpit. After reading the suggestions made by every one I'm begining to wonder about the location of the radio, it is right under the ignition switch and before it was on the other side of the cockpit.

    Now I'm anxious to get back out there and start it up and then trythe radio on the side of the cockpit opposite the switch.
     
  6. Jan 23, 2008 #6

    Rhino

    Rhino

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    Could be the radio too. I traded in my SP-200 for an Icom, for that very reason. The SP-200 was far more prone to outside interference and crosstalk. It's a good radio, but the Icom worked much better for me, and Sportys didn't charge me anything for the trade (it was still new).
     

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