SWR and a Balun problem
- MEC131
- 4 PILL USER
- Posts: 27
- Joined: May 09 2011, 22:45
- Real Name: Ronnie
- Antenna: K-40
- Radio: Uniden Grant XL
- Contact:
SWR and a Balun problem
I have something wrong that I do not know if it is really a problem or not....I live in a bacement aparment that is only half way blow ground I have a k-40 mounted to a cookie sheet and that mounted to a camera tripod....I have 8ft ceilings and the k-40 tip is about an inch or so from touching the ceiling....the cookie sheet is about 15x 10 inches mounted horizontally....I have the K40 mounted to the lip of the cookie sheet....this cookie sheet works as a ground ....I have a grant xl ...I have 2 pieces of coax with a thing called an ugly Balun....is is just a plastic tobaco can wraped in about 20 feet of regular cb coax I got from the CB dealer here in town between the 2 pieces of coax.....the balun has 2 terminals on top of just a nut and bolt the are for hooking an antenna to.......the thing is when I hook the balun up backwards that is with the 2 antenna terminals hooked to the lead from the radio and the other lead ment for the radio to the K-40 I get a low swr of 1.7 on 27.555 and 2.5 on channel 1 regular CB but when I hook the balun the oppsite way or the way is is suppose to be hooked up I get high swr right across like alomst 3 on 27.555 and well over 3 on channel 1 regular cb.....should I use the radio with the balun hookup backwards with the low swr....could it damage the radio in any way.....I tried hooking the balun up the right way 3 times and always got high swr....is there really a problem here.....Thanx Ron
Ron,
It won't make any difference to the radio if the balun is run 'forward' or 'backwards'. If running it 'backwards' results in an acceptable SWR, then have at it.
Your setup is a 'compromise' at best, it isn't 'right' in any sense. That cookie sheet isn't going to be even 'close' to right for a groundplane at 11 meters. It makes for a good place to connect a few radials to, but that's about it. I have to think that the feed line is acting as the 'groundplane' or 'other half' of the antenna. Your setup may result in a low SWR, but SWR by it's self doesn't indicate the usability/performance of an antenna system at all. It only tells you something about impedance matching, and isn't very 'smart' about doing that.
If your setup works, then it's certainly better than nothing! Just don't count on much, you know?
- 'Doc
It won't make any difference to the radio if the balun is run 'forward' or 'backwards'. If running it 'backwards' results in an acceptable SWR, then have at it.
Your setup is a 'compromise' at best, it isn't 'right' in any sense. That cookie sheet isn't going to be even 'close' to right for a groundplane at 11 meters. It makes for a good place to connect a few radials to, but that's about it. I have to think that the feed line is acting as the 'groundplane' or 'other half' of the antenna. Your setup may result in a low SWR, but SWR by it's self doesn't indicate the usability/performance of an antenna system at all. It only tells you something about impedance matching, and isn't very 'smart' about doing that.
If your setup works, then it's certainly better than nothing! Just don't count on much, you know?
- 'Doc