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Brody
August 17th, 2009, 06:55 AM
Randy, I guess this one is for you as you seem to be the resident CB expert:

You know what my Cb set up is, so here is what I did:

I re ran the antenna wire, a new 9' one with factory ends, and relocated my antenna to the far rear of my rig off of the roll cage, and welded the new mount about 18" off of my bumper which keeps it clear of most of the metal. I adjusted my settings so that it remains in the 1-3 setting in all bands.

What is happening is that, even in 'line of sight', I get very intermittent contact. In fact, during the Red Cone run, we only heard someone else one time and that was when we were directly above them on some switchbacks.

I have noticed that most of the adjustment dials have static when I turn them, so am wondering if the CB simply needs a good cleaning with some electronics parts cleaner.

The CB is well grounded and has a good clean power source.

WINKY
August 17th, 2009, 07:06 AM
Could possibly be the cb itself. If you have no coils taking up the slack and a new coax it could be either the antenna is not properly fitted to the mount (yes there is a specific way to do this) or the cb is failing. (crystals going bad IC's failing or aging) I could put my cb in your rig and see if the antenna system checks out, and if it is clear your cb might need to be worked over or just replaced, sometimes the latter is cheaper.

With antenna placement to get the best out of it you want the antenna above as much "metal" as you can as the metal reflects rf back into the antenna burning out the radio over time or very quickly, this is refered to as SWR. On your meter you want the swr to be as low as possible 2.5 is ok but 3 or higher will start to degrade the radio.

But it seems you may just need another cb as yours sounds like it is just aging since yo have static all over the channels.

One thing to remember is that running a shorter coax you need to tune the antenna to the radio. most places recommend 18' coax as the resistance will be 50ohm which is vital to proper antenna efficiency. with a shorter coax you need a longer antenna. I know you dont want 18' of coax or a tall antenna but you must have one or the other or you will have a cb that just wont work. shortcutting around these requirements is not recommended.


yet another quick read.
http://www.rightchannelradios.com/pages/cb-antenna-tuning-guide-pv-c0-61.html

after getting mine placed properly i get a swr of 1 or less on all channels.... :D

Brody
August 17th, 2009, 07:37 AM
Thanks, Randy! I'll check out the link, but keep in mind that I am looking for a 'performance 'level' of only about one mile. I just want to keep in contact with the group that I am riding with on the trail and when we are on the road.

I was getting this briefly before I changed the antenna wire and placement. What I did should have improved the reception, whether or not I installed a longer wire, as I don't really need distance. People have better luck with a magnetic mount antenna than what I am getting, so maybe it is the radio. Where it is located now is about as far from any metal as I can get it on my rig unless I mount it way up high, where it won't last very long...It came with the 84, was old to begin with, and so it may very well be the radio itself.

I am going to get some electronic parts cleaner and hose the damn thing down with it to see if that helps. It sure isn't going to jack it up at this point....

Brody
August 17th, 2009, 12:10 PM
Took it apart and hosed it down with about a half can of electronic parts cleaner and a couple of brushes. Nailed it with some air, did it again and put it all back together.

Must have been really dirty as it seems to be working fine now. I am below 3 on all my channels and was picking up people way out on I70 in both directions, so it will probably work good enough on the trail rides.

WINKY
August 17th, 2009, 05:49 PM
but keep in mind that I am looking for a 'performance 'level' of only about one mile. I just want to keep in contact with the group that I am riding with on the trail and when we are on the road.

I was getting this briefly before I changed the antenna wire and placement. What I did should have improved the reception, whether or not I installed a longer wire, as I don't really need distance.


Pete, your not understanding that with a shorter coax the radio is not working together with the coax and antenna, the radio is engineered to work with 50ohm total including antenna, when this isnt so it doesnt matter what you do the radio just wont work well if not at all. coax length has nothing to do with distance remember your only pushing 4 watts if that. The antenna must be the correct ohms in order for 4 watts to be transmitted through the cable and antenna properly to even make it to the air and vice versa.

Its like me giving you a dress to wear, yeah its clothing yeah it will keep you from being nekkid yeah it will do the job but it just wont work on you... and it will look funny too...

I also think the radio might be old too... but you gotta have the proper ohm'd cable antenna combo and the reason why the walmart megnetic antenna work is they are engineered to 50 ohms regardless of cable length (resistors, extra winding in the antenna etc..)

Andrew
August 17th, 2009, 05:58 PM
Yeah what kind of antenna and is it grounded well?

Brody
August 17th, 2009, 06:06 PM
Oh, I am understanding it fine. I have no more money to spend on it so it will either continue to work or end up being a 12 gauge target. I had $10 to spend on an antenna so I got the 9'. I didn't have the $22 to spend on the 18'.I was picking up some real yeeha mush mouth boyoboys on I70 both east and west. That is good enough for me. If I get a mile out of my CB, then I will be talking and listening to the people I want to talk and listen to...the people I am doing a run with...

I just don't understand why, when people talk on the CB, that they all have to talk as though their IQ was now the same as a rats and do it with a crappy inbred southern accent to boot. I have had a CB when I was on the easy coast and up in Canada and they talk like that there! I mean, I am more than well aware that there are some really dumbass people out there, but why get on the CB and actually advertise the fact? Oh, And I am from south of the Mason Dixon Line and grew up around people making a mockery of English...

It is your basic 4' firestick style antenna, BTW...and grounded to the roll cage, which is grounded to the frame, which is grounded to the battery, which is grounded to the body...

WINKY
August 17th, 2009, 06:10 PM
Gotchya pete, also too it is good to test your cb with another that is known to work also. You could have had some on the trail run that had bad cb transmission...?