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Need Help

Old 07-18-2005, 07:01 AM
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Default Need Help

I have a Icom 602,Shakesphere 5102 antenna, and a Northstar 951 gps plotter. My problem is that when the vhf is on say the weather channel and I turn the 951 on the clarity of the reception gets worse. It almost gets to the point that you cannot understand what the weather report is saying and prior it was very clear. If I have the vhf on say channel 16 and I turn the 951 on I have to turn my squelch up to accomodate for it. Currently the power for both go to the same fuse block. I have temporarily seperated the power wires to seperate fuse blocks but it is no better. The grounds go to the same location. What do you think I need to do next? The antennas are located on opposite sides of the t top. Any ideas? Please help.
Old 07-21-2005, 02:06 PM
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Default RE: Need Help

I have tried putting foil around the antenna connections on the back of the units but no luck. I was hoping some one would have some suggestions.
Old 07-21-2005, 03:09 PM
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Default Re: Need Help

Check your battery and seperate your ground. I believe my VHF is ground directly to my battery. Other more knowledgeable members will chime in...
Old 07-21-2005, 10:04 PM
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Default Re: Need Help

It's not the power wires, but it could very well be a bad ground on one or both units. Make sure both units ground connections on both sides of both wires are nice and tight, rust free... Then, make sure what your grounding them to (ground block, metal screw...whatever..) is also REALLY a ground(again check connectors...). I've seen folks "ground" things to screws which were screwed into fiberglass. In otherwords, that ain't be no ground. If that doesn't do it, then make sure your RF grounds(sheild wires) on the units are also grounded, preferrably to a separate RF ground (grounding plate, your thru hulls...). If you have no RF ground on the boat, just connect them to the same ground as the other grounds are. If that doesn't do it, try one more thing. Try grounding the base of your VHF antenna. I don't know why this sometimes helps RF noise (which is what your problem is, you have RF noise), but it does for some reason. By grounding it I mean, if the base is attached directly to fiberglass or other non-matalic un-grounded material, then run a ground wire to the metal antenna base. Try just a temporary peice of wire run to a good ground, and see if that helps. If it does, THEN do it permenantly.

Lastly, one or both of the units, and I'd guess the Northstar is the problem, is faulty and needs to be serviced because it is throwing off too much RF noise. It might have an internal problem (bad solder joint...) which is throwing out the noise. The above are all easy items to try, so try them before sending the unit off to repair.

Hope that helps and good luck.

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