UHF coax antenna connections

[hiluxdan]

Well i finally got me a uhf radio, a gme 3400 second hand with 2 antennas.
Problem is the plugs have been cut off the transiever end of the antennas.
I picked up the plugs today from dick smiths but they had no idea about how to connect it to the cable.
It's a crimp type plug.
I know i have to strip the shield to get the core in but not sure what happens with the shield, is it suppose to contact the outside of the plug under the crimp or not contact the plug at all?
I know there is some rule like this for tv coax but not sure exactly.

And also to switch between different strength aerials. Is there a switch that you can use, or is it just a matter of unplugging one and plugging the other one into the radio?

Is there any issue with where the antenna is fitted (they are ground independant) One of them is too long to fit on top of the bull bar, so it has to sit down behind the loop on the flat. I know this will reduce its performance slightly, but can this do any damage to the tranceiver itself.
Thanks
Dan

[ROLLUX]

hey dan, there is a special coax cable cutter and crimping tool for the plug you should be able to get them at dicksmiths as well
in the coax cable there is the core the wire white shielding the silver braid and the outer black shielding.
the coax cutter cuts the diffrent layers at the right length. the inner core has a terminal that crimps to it. that and the white shielding goes in the centre of the plug. the silver braid goes on the out side of the plug stem where thw cable entres then u place the locking sleeve over it and crimp

hope this helps

[hiluxdan]

Clear as!
thanks

[jcarter]

and just to add, Comms places well one i went to anyway charged something incredible like $45 p/hr for labour + parts.

so to get a 1m ext cord + both ends crimped ended up costing like $25.

well worth learning/purchasing the crimper's to do it yourself if you can.

[rodw]

You can also get a solder on connector. You fold the outside braided shield back over the outside of the cable and solder the centre wire in and screw the outside collar down on the plug. That's the way I did the last one I did and I had to remove the bullbar a coupe of times which meant I cut the end ff and resoldered it a couple of times. ou fgo tto cut the plug off to uninstall the antenae! This type of connector I think came with my antenna and thus for a few minutes more work, the installaton was free!

But I have a Weller temperature controlled solder station which makes the job so easy to do.

You should not have any joins in the coax as you loose signal. A friend cut a cable to install a new bull bar and inserted a plug and socket to rejoin it on a petrol Patrol. You could hear the engine every time he presed the talk button because the outer shield was compromised.

Last time I was at a Comms shop, the guy was lamenting "if only those guys who mount their antenna low knew how much signal loss this caused and how much this stresses their set becasue of the uneven signal risked damage to their set" or something like that.. Anyway, I listenintently when he tells me how to install a CB.

Rod

[9W6VX]

Dan,

If you want to use two antennas on a radio, you can use a antenna switcher which will allow you to flip a switch to use which ever antenna you choose.

I used to have an antenna switcher on my VHF mobile rig and I used a 1/4 wave and a 5/8 whip antenna.

If you really want to be sure that your antenna and radio is tuned, you can use a SWR meter. Most radio installers should have one. We aim for a SWR ratio of 1.5 or less on the centre of the frequency band.

I am not familiar with the Australian UHF frequency band so I can't be of more help.

I'm sure there are some radio gurus members based in OZ who can help you.

Cheers

Brendon

[9W6VX]

Dan,

Have a read at this link.

Not too technical and it's easily understandable.

http://www.technolab-inc.com/html/Tech/swr_tech.htm

[hiluxdan]

Thanks fellas. All sorted and working.
Had to put the antenna low on the bar, wouldn't fit in my garage, BUGGER!
I found that my standard crimper/strippers did a nice job on the connection.
I figure for $3 it would cost me more in fuel to go swap it, and i'm a bit inpatient like that, when i start a job i just wanna finish it one way or another.

Brendan i checked at one electronics store but they didn't know about the antenna switch. Will try a comms store this week.
Would have just got a mid range antenna but cos they both came with the radio I might as well use them.
Hey Rod what range do you use most on the soldering iron for auto leccy stuff? I want to get one but can't see i'd use it enough to justify getting a variable one.
Thanks
Dan

[rodw]

Mate, years ago, I bought a Weller temperature controlled soldering station. Best investment I ever made. It has no controls, the tip kicks in and out with an elctro magnet somehow I was told once. Perfect job every time, even on really heavy guage wire that you would't think this little tip would handle at all!

Rod

[9W6VX]

Dan,

This is what I used as an antenna switcher. It's a Diamond from Japan and it's a very reputable brand.

Cheers

Brendon

[9W6VX]

[9W6VX]

Here's the link:

https://www.rfparts.com/diamond/cx210a.html

Cheers