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Therealporkchop
Junior Member
Username: Therealporkchop

Post Number: 30
Registered: 11-2002
Posted on Monday, May 24, 2004 - 8:44 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Here is one for you...I have a 2004 Sterling LT9513. It has factory mirror mounted dual antennas. The factory stereo is wired into them somehow, but checking them gives a fairly good swr, about 1.5:1. Take the same truck, mount your own mirror mounts and the swr goes all to, well, you know. OK. Got a Wilson 1000 mag mount, the farther toward the front of the truck I go, the worse my SWR gets, the closer to the bed, the better. But the SWR still stink's, it's over 2. So, changing the antenna didn't help either(another Wilson 1000). I am running a Galaxy 77 and Texas Star HDV350. How is the correct way to check the SWR first off. What can I do to get my SWR low? I don't want to communicate, I do want to broadcast. Would I be better off with the 102" whip or what? I want to be heard for miles away, loud and clear. What would be the correct length of coax to run from my radio to my amp? And what type of coax should I use? Will the mag mount Wilson 1000 do the job or do I need a 5000? OR would two 5000 truckers on the factory mounts work? They have the small coax run from them. OR should I scrap the mag mount and run a steel whip? If I run the still whip, where would the best mount location be? Anyone with any real tech advice on this, please help as this is really starting to bother me.
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Tech808
Moderator
Username: Tech808

Post Number: 2465
Registered: 8-2002


Posted on Monday, May 24, 2004 - 11:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Therealporkchop,

It sounds like your Factory Antennas are grounded thru your Electrical system in the truck with your radio.

When you Mount Different Mirror Mount antenna's and your SWR Goes up sounds like your CAB/Mirror Mount's/Door's is Not grounded to the frame.

I had this same problem with our 2000 KW & 2000 Pete's.

I ran wire's Direct to Frame and Pulled Power Direct from Batteries and that solved our problem.

You might also want to check with the Sterling Dealer and see if there has been a Service Notice on this problem.

I have found Most all Factory Coax in Big Truck's is 100% JUNK and bareley able to handle 4 watts let alone an AMP.

Just my experience with Factory JUNK Radio Hook Up's, Coax and Antenna's in Pete's and KW's.

I changed the Factory Coax to Regular Mini 8 and ran up along Mirror Mount's (Nylon wire tied) thru Top of Cab Down inside of windshield frame on both side's to radio. I also installed Different Antennas to handle the Power.

I used A 12' Co-Phase Harness from Both Mirror's to Radio.

I never had any problem's after that and had a 1.1 to 1.5 across the bands. Also had my External speaker wired behind the driver's seat and NO feedback.

To make thing's easier I did not solder the PL259's on Until I had Everything inside the cab.

I also done this conversion to Beerman's CEF 322 2000 Pete and added a Single Astatic 3 KW Antenna from Copper and I can generally talk with him up to 25 - 30 miles away most everyday and he hauls a Slip Deck Trailer.

Hope this help's.

Lon
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Therealporkchop
Junior Member
Username: Therealporkchop

Post Number: 32
Registered: 11-2002
Posted on Saturday, June 05, 2004 - 8:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok, here is an update to my problem.

I'm running a Galaxy 77, with a Texas Star 350HDV. I just got a new Wilson 5000 magnet mount. I can get a pretty good SWR when I only have the radio on, but with the amp on, my SWR goes up and I can't seem to bring it down. I usually get a reading of 1.5:1 or less with just the radio and usually 2.0:1 or higher with the amp on. It seems that if I run the amp on the low side or dial the power down with the knob, the SWR is higher. If I run the amp straight wide open the SWR is lower, sometimes I've seen it as low as 1.5:1 and seems to fall when you speak into the mike. The closer towards the bed I move the antenna, the better my SWR seems to be. The closer towards the front of the cab I move it, the worse it gets. I am also experiencing problems with my pre-amp. When I first installed this stuff, the pre-amp worked fine, now I get a buzzing from the amp when I try to use the pre-amp.

What is going on with this set-up? What length of coax should I run from my radio to my amp? My amp is directly hooked to my batter and my radio is in the overhead hooked to the factory power jacks. I feel that this combo should be broadcasting me way out there, but sometimes it just seems that I can't be heard.

Thanks
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Gumball
Junior Member
Username: Gumball

Post Number: 10
Registered: 10-2004
Posted on Sunday, November 07, 2004 - 9:19 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I had a similar problem trying to run a radio/ amp setup in a Volvo. I finally grounded EVERYTHING:
antenna mount bracket-to-door
door-to-cab
cab-to-frame
battery-to-frame
alternator-to-frame
amp & radio chassis-to-cab

Use stranded cable or "woven" strap,
keep each piece as short as possible

It was a lot of work, but it made a big improvement.
Have fun..........

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