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Dutchman
Posted on Thursday, August 16, 2001 - 10:46 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I've got a M400 Starduster mounted on the end of a mobile home. The lower end of the radials is about 10 feet above the roof. I get TERRIBLE TVI in here even when I just dead key at 4 watts. Totally blanks the TV screen!!Haven't even hooked up the amp yet!! I have a 5000watt capable tvi filter coming for the radio,and am going tomorrow to get high pass filters for each TV. SWR is low,at 1.2-1.3 with PDC 600 meter inline..1.1 when I take it out.
The question is,is the fact the mobile home has a metal roof part of the problem????
Will the filters be enough??
I intend to push the antenna up another 20 feet(to 50 feet ground to top)will this help???
Also,saw a guy who has an Astroplane laying behind his house,am going to make him an offer....would this antenna,which is not a base fed design,be less likely to kill the TV's when i key up????

Help!!!
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vernonott
Posted on Friday, August 17, 2001 - 3:17 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If you are running cable T.V. or Dish ,you should have no problem.On the other hand ,if you are running a old time element antenna I doubt all the filtering in the world will clean it up.
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ChillyDog
Posted on Friday, August 17, 2001 - 7:08 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Dutchman,

Are you running a non-modified radio, or has the modulation been "opened-up"?

My personal opinion is until you have no TVI issues with a stock radio, you should avoid running amps, gain antennas, or modified radios. If you are working with a modified radio all bets are off!

First thing to check (on a stock radio) is adequate grounding. It is possible to have a stock radio in the same room and on the same A/C power circuit as a TV without interference to either unit, if you have good grounding.

Good luck!

Bob
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bruce
Posted on Saturday, August 18, 2001 - 1:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

raising the hight of the ant will help running a stock radio will realy help. If your problem is overload it should go away if there is no change in the problem and EVEN with a filter on your radio a GOOD FILTER !!!! try a HIGH pass on the tv if you are still picked up or can be picked up with no ant on the tv then i would contact the TV manufacture see if they have any sevrice bolos maby this set has a problem
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Anonymous
Posted on Tuesday, September 18, 2001 - 3:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Tha astroplane could possibly help since the voltage on the elements is lower near the base of the antenna. I have heard this same thing from other people too. One guy (the rabbit) ran a 500 watt amp w/o TVI on his old astroplane that was up 40 feet for 15 years or more. When he 'upgraded' to an imax2000, the neighbors went ballistic! Too bad he crunched the astroplane taking it down. Now he's sorry he ever did it. If it works for you, let us know!
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Hook
Posted on Tuesday, September 18, 2001 - 2:41 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a I-Max on a 10 ft pole leaning against my mobil home (temporary) with the TV ant about 30 ft away from the I-Max and with the amp cranked all the way up-MUCH more than 500 watts:)I have no TVI at all. I use 3 ground rods,1 for radio chassis, 1 for amp and 1 for I-Max. Works for me!
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Westwind
Posted on Sunday, March 24, 2002 - 1:56 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I was looking at the post by Hook and I was wondering if anyone else uses this kinda setup with 3 ground rods?If so,how long should the ground rods be and how far should they be in the ground?I'm having trouble getting my ground rod in the ground because of where I live.There's alot of rock in the ground around here.Any suggestions?Also,if I use 3 ground rods where do I hook to the radio chasis?Any where on the back?I was thinking about buying a masonary drill bit and welding it to the end of the grounding rod then renting one of those big drills and drill the rod into the ground right thru the rocks anyone think this will work?Please respond...

Westwind
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Taz
Posted on Monday, March 25, 2002 - 8:40 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok, TAZ'S rules of grounding cb equipment

1.) NO GROUND WIRES OVER 8 FEET LONG!!!
2.) USE 8 FOOT GROUND RODS
3.) ALOT OF PEOPLE WILL DISSAGREE BUT NO
ROCKSALT! IT WILL EAT THOSE GROUND RODS UP!!!
I HAVE DONT IT AND SEEN IT HAPPEN SO TAKE
MY WORD FOR IT AND DONT DO IT!
4.) USE A GROUNDING STRAP OR ACORN TO
CONNECT WIRE TO GROUND ROD.
5.) TO GEOUND CHASSIS JUST PUT A TECH SCREW
WITH AN EYLIT
6.) USE NO SMALLER THAN 12 GUAGE WIRE.
7.) KEEP GROUND RODS WET OR PUT IN A DAMP
AREA THAT GETS LITTLE SUN.

8.) I PUT MINE IN WITH A HAMMER AND I LIVE IN THE DESERT. GET A SLEDGE HAMMER. IT WILL WORK. I USE A 20 OZ CLAW HAMMER AND I AM 14! USE A POST DRIVER. I THINK THATS WHAT THERE CALLED.
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Taz
Posted on Monday, March 25, 2002 - 8:41 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

USE AS MANY GROUND RODS AS YOU CAN!!! THE MORE THE BETTER!
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Westwind
Posted on Wednesday, March 27, 2002 - 9:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Taz,Thanks for the info the only problem is I'm having trouble getting the ground rod in the ground.You see,I live in Nashville,TN. and the ground around here is more rock than dirt.Every where I try to put it in my yard I get it about 3 or 4 foot down in the ground and I run into rock.I guess what I'll have to do is get a post hole digger and dig a hole and remove all the rock then put the ground rod in and backfill the hole.You say I need to use as many rods as possible.OK if I do where do I hook them?I only have the antenna and the radio.Do you mean I need to hook acouple ground rods to each?And I was reading the instructions on the IMAX2000 and it says to use a static electricity discharge unit between antenna and set.Do you know what that is?One last thing-What is a Acorn?

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