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  1. #11
    Feeling like an "old timer." RRR_K2's Avatar
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    The noise is constant (when sending, receiving, or just listening), and I know for sure it's the Terratrip causing it because when I turn it off (and back on) the noise stops (and starts). The filter is plugged into the factory cord for the radio, so there's about 6 inches of wire between the two (and about half of that is taken up by a fuse). The Terratrip is mounted above the glove compartment and the radio is mounted on the back of the center console/arm rest (between the front seats). Even though they both use separate power wires, the wires enter the cabin in the same bundle, though they split before the filter for the radio.
    Matt Kennedy
    www.RockyRoadRacing.com

    Good drivers have dead flies on the side windows. - Walter Röhrl

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  3. #12

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    Yep, that is the same problem I have. The solution is to use a different frequency. Perhaps we should contact Terratrip and see if they have a solution.

  4. #13
    The Scorpion King John Sundelin's Avatar
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    Quote Originally Posted by RRR_K2 View Post
    The noise is constant (when sending, receiving, or just listening), and I know for sure it's the Terratrip causing it because when I turn it off (and back on) the noise stops (and starts). The filter is plugged into the factory cord for the radio, so there's about 6 inches of wire between the two (and about half of that is taken up by a fuse). The Terratrip is mounted above the glove compartment and the radio is mounted on the back of the center console/arm rest (between the front seats). Even though they both use separate power wires, the wires enter the cabin in the same bundle, though they split before the filter for the radio.
    Since I don't have a Terratrip, forgive the stupid questions, but (1) is the case plastic? (2) is there any part of the case that is metal that is electrically tied to the battery return wire? [can check with an ohmmeter] (3) can you disconnect the sender from the unit? [I am assuming that you have a wheel sensor] (4) do you have any other wires running out of the Terratrip, such as a reset switch? If the answer to (1), (2), and (3) are yes, and the answer to (4) is no or that you can either disconnect or bring all the switches close to the unit, the first thing I would do is disconnect them one by one and see if the problem goes away. If it doesn't (don't laugh...), I'd get some heavy duty tinfoil and wrap the Terratrip in it, making sure that it's completely covered and that that the tinfoil is tied to the metallic part of the chassis. If that makes it go away, this might be a difficult problem to solve.

    --
    John

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  6. #14

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    1) The case is plastic. 2) I assume somewhere inside there is a connection to the negative lead from the battery but none of the case is metal. 3) a little difficult as power, reset, pickup units, etc all go through the same plug on the back of the Terratrip 4) That would isolate which one of the wires, if any, is acting as an antenna. That wire could then be changed to a shielded cable. And tin foil might work. However, the problem is so frequency specific that simply using another frequency still in the 2 meter band works.

  7. #15

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    Just some food for thought from someone with a bit of experience in electrical do-dads:

    DC batteries actually have a flow of electrons from "neg" to "positive". So your noise may very we'll be coming from your ground (chassis) and that is why running a direct neg to a battery can help. You could try filtering the ground as we'll.

    Avoid running high amperage or high gain wires (like your antenna) parallel to any power lines to the radio. Cross at right angles as this will reduce or eliminate the induction of unwanted frequencies.

    Shielded cables can be (and often are) terminated incorrectly. Ground ONLY one end of the shielded cable. This protects unwanted freq from induction into the cables inside. By grounding both ends you build a mini transformer.

    If all else fails, find a scope and hook it up to your power supply to the radio, you can find all sorts of interesting things traveling threw the cars power lines.

    Have fun
    Last edited by zerodegreec; 03-19-2014 at 06:13 AM.
    Bryan L.
    Maker of those intercom adapters and "stuff"
    www.zerodegreec.ca

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