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Airplane1
Senior Member
Username: Airplane1
Post Number: 1093
Registered: 5-2004
| | Posted on Thursday, October 23, 2008 - 11:14 am: | 
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I hope it is ok to post this here as I posted it on and old thread but not sure if it will get the exposure I want.
I need help with a ground problem and hope Tech 833 sees and can help me with this. I just put my tower up, it is 30ft + 6ft of mast so my maco 5/8 is 36ft to feed point now and ran a ground wire from the base of the 5/8 on the mounting bolt on the antenna down to a 8ft ground rod beside the base of tower.
Now I was having tons of problems after hooking everything up. I was so happy I finally got the tower up and grounded thinking I am set going from 7ft at feed point with no ground to 36ft with ground.
Well I started making contacts far away like 50+ mile, I was so happy but then in comes the XYL. Well let me tell ya she was mad as you know what.
I was killing the tv, I would come accross it very little at times but it was only on my 2970dx and not the ham gear. Well it was all my radios now and instead of comming over a little it was wiping vthe tv out totally, no pic just snow and a loud hum.
Now this stinks as I read that grounds helps tvi go away and the receive get quieter and thoght wow, my 2970dx will stop affecting the tv with the antenna up at 36ft and grounded.
Now I have good clean connections with penatrox, the coax is bury flex low loss sheilded and in great condition and the connectors clean and,dry and new. Well I did not think the ground was the problem, I was trying every thing and going to get the filters and beads to snap on cords, isolating the tv to another circuit and so on till a friend said befor spending the money on all that try disconnecting the ground wire from the rod. Guess what, the problem went away and now the only radio affecting the tv is the 2970dx again and it is not bad, just a few lines but no hum so it is bearable.
Now I need to understand this problem. I know it is working now but that is not good enough for me. I hear and read all the time about the importance of grounding but but it does not work for me.
The big question is WHY????
Thanks, sorry about the spelling.
AP |
Streaky
Intermediate Member
Username: Streaky
Post Number: 189
Registered: 3-2006
| | Posted on Thursday, October 23, 2008 - 9:37 pm: |
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36 feet is pretty much a full wavelength on 11 meters Iwould try grounding the leg of the tower to your ground rod then a short piece of braid from tower to mast and then another to antenna trying to break up that 36 foot run that may be radiating
Hope you find the prblem
Streaky
CEF#805
CVC#98
WorldRadio805
The Craziest Station in the Canadian Nation
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1095
Registered: 5-2004
| | Posted on Friday, October 24, 2008 - 7:13 am: |
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I thought that too 36ft being a wave length but if I use the tower and connect it all like mast to tower then tower to ground it will measure about 36 ft also so would`nt the tower radiate? I will try and see.
AP |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2665
Registered: 1-2005
| | Posted on Friday, October 24, 2008 - 10:43 pm: |
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Why do you have to connect a ground wire at the base of the antenna? If the base of the antenna is metal, and the 6 foot mast is metal, and the tower is made of metal.......would'nt it all be connected as one piece anyway? You see? Then you just connect the base of the tower to the ground rod. No more TVI and antenna is grounded!
Kenny
CEF491
Reading the mail around Indianapolis Indiana!
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Airplane1
Senior Member
Username: Airplane1
Post Number: 1096
Registered: 5-2004
| | Posted on Saturday, October 25, 2008 - 11:15 am: |
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I did not do the antenna to mast to tower then the tower leg because the tower was galvanized and was not a good connection. I guess I should have sanded off the spot at the bolts and put a short piece of copper between the bolts to get a good contact between the sections and then at the base.
I can tilt it down one sat. morning and do that to see if it works.
AP |
Streaky
Intermediate Member
Username: Streaky
Post Number: 190
Registered: 3-2006
| | Posted on Saturday, October 25, 2008 - 11:45 pm: |
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My thinking is that the strap does not radiate as much as a solid piece of copper wire and may break up the radiation pattern hopefully this will help
Streaky
CEF#805
CVC#98
WorldRadio805
The Craziest Station in the Canadian Nation
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