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Crafter
Posted on Monday, June 02, 2003 - 2:10 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If you havnt tried one yet get a good low pass filter (Drake or Bencher) are my favorite. As for the implant Im at a loss if the filter doesnt work your going to have to detune the modulation I bet. The truck think sounds like a ground problem.
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Kc0gxz
Posted on Monday, June 02, 2003 - 11:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Therealporkchop

You said that your antenna is just outside of your computer room. You're kind of vague there and not telling us much. How high is it in the air? 28 feet or higher I hope.

Big Sticks are DIRTY antennas. Just like the A-99s. They're like a little kid. They get into anything and everything. Get your antenna as high as feasible. And I do mean HIGH. Those antennas are TVI trouble.

DO NOT USE RADIO SHACK COAX!!! That stuff has such poor shielding you could screw a dummy load on the end of it and hang it vertically up in a tree and it will transmit farther than your average CB walky-talky. If you need 50 feet or less of coax, you can easily get by with Belden MINI-8 coax. It has far better shielding. No matter what brand of coax you use, be sure that it is at least 97% shielding or better.

How far are your computer speakers spread apart? The speaker leads act as a receiving antenna when ever strong RF is present. Try replacing them with shielded speaker leads. Open the speaker cabinets and solder a .001 or .01 capacitor across each speaker.

I'm willing to bet that you are running your mic gain wide open on those G-44s. That will usually cause feedback when the echo and talkback are turned on especially if the external speaker is too close to the microphone.

Crafter has a good idea as far as using a low pass filter. Try it. If it doesn't help, that tells me that you definently have a antenna highth and/or coax problem.

I hope I was of some help to you. Good luck.

Jeff, kc0gxz.
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Therealporkchop
Posted on Sunday, June 08, 2003 - 1:12 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for answering and your help. Thanks for the email. I'm not running the mic gain wide open. My talkback is disabled due to the squeal I get in it since I tuned on it. I guess I need to find myself a better antenna. I'll be moving soon, so I'll relocate all my stuff then.
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Tech833
Posted on Sunday, June 08, 2003 - 11:25 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

It sounds like a lot of that '22 watts' may be just 'lawn' and splatter. A watt meter is an unintelligent device in that it cannot tell the difference between 22 watts on frequency and 22 watts spread all over the radio spectrum.

I highly suggest you view the baseband output of that radio on a spectrum analyzer and see how little is going out on your desired frequency and how much is going everywhere else (like the clock sync frequency for your computer, etc.). Spurious operation is illegal on any band.
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692
Posted on Sunday, June 08, 2003 - 1:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Porkchop.
If your antenna is just outside the window
your picking up RF of the antenna. Get it up
away from your equipment. On the dump truck
check your swr. Make sure your antenna is as
far away from from the cab protector as possible.
Or anything metal for that matter. Also i would
strongly suggest a noise canselling mike. Astaic
636L/Roadking56. A must for a truck enviroment.

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