UHF splitter
- Thread starter hawkinau
- Start date
Gidgee
Active Member
You can actually do it with a splitter/combiner but they aren't cheap for 5W Tx power and at best you have halved the power going to each antenna. Add to that if the two antennae are too close (say on the bullbar together) you will get some really weird directionality. And while I'm on that, I see lot of people with 2 antennae on the bullbar, and even if only one is being used, the passive one will still introduce that unwanted/random directionality. Simply put, it is outright crazy to do this. Best place for any antenna is on your roof rack, and a 2dBi there could well outperform a 6dBi in some directions.
Batts88
Well-Known Member
We use to get told the best place fo the old CB antenna was the centre of the roof but it's not practical so mounted on the bullbar is good enough for us amateur users.
I think both my 2 uhf's have a 6.5dba antennas mounted on the bullbar, both get a good range sitting next to each other another one on ch 40 other ch39. It may not be ideal for those who are perdantic about their coms but is fine for the average Joe.
I think both my 2 uhf's have a 6.5dba antennas mounted on the bullbar, both get a good range sitting next to each other another one on ch 40 other ch39. It may not be ideal for those who are perdantic about their coms but is fine for the average Joe.
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Petunia
Well-Known Member
That was then when ground dependant was used, now ariels are ground independant it does not matter if you hang them upsidedown in a tree.
And speaking of two aerials, back then I did have 2 ground dependant 27meg one each side simply both jambed in the one coax connector and then jambed up the radio. Before I had my own SWR meter, I had to go down town to see R [rip] in the radio shop [ he went out with my sister for a while ] to get that ''weird'' setup SWRed. R whacked his meter on and he knew his stuff, if the 2 aerials were 1 inch further apart they would be an exact quarter wave apart and been so super cool and powerful and stuff, I was young, once.
Triton14
Well-Known Member
Out of curiosity how would you do that??
My GME antenna is hard wired all the way through I believe??
Gidgee
Active Member
Position of the antenna is not just ground related. Any metal near the antenna can/will absorb transmitted power and block received signals. Additionally it can act as a director/reflector which may help but more often will skew the radiation pattern in a (likely) undesirable way.
If you are looking to talk to your mate 1km down the road it's irrelevant. If you are wanting to communicate with other track users to avoid head ons as you are going up and down dunes,or are needing help, then it's rather more important.
If you are looking to talk to your mate 1km down the road it's irrelevant. If you are wanting to communicate with other track users to avoid head ons as you are going up and down dunes,or are needing help, then it's rather more important.
sharkcaver
Well-Known Member
If its a fixed base then you cant really.
That's why I got an antenna with an so-239 base - the ae4701.
To that I run 3 aerials off it, the 6.6 colinear whip that came with it, a flexible 3di whip and a unity gain 1/4 wave whip.
The 1/4 wave is the standard 1/4-26 thread and its mounted on a loading coil from ZCG.
I pick and choose between aerials, the tighter the bush, the smaller the aerial. I use the 3dbi the most, even on those longer trips, bcause generally, I'm not that far from my company. Rarely do i ever mount the 6.6Dbi.
Triton14
Well-Known Member
Ok, thanks.
I was given the CB & antenna for free which is a GME TX3420.
I guess when I find the need to upgrade antenna's I will deal with it then.
Chhers.
Gidgee
Active Member
red hilux
Well-Known Member
Exactly. To prove that point take a look at any TV antenna. The only ones in a TV antenna connected to wires are the collectors ( round ones) shown here. the rest are guides and not connected to anything. 2 close antennas on a vehicle or other bits of metal like a bonnet or bull bar do the same thing. 2 antennas close to each other tend to send the signal to the sides of the road and reduce strength in line with it.
High and clear are the rules for mounting an antenna on a 4wd.
MrHorsepower
Member
my solution was to have 2 x GME antennas AE 4705 6.6DBi and AE4704 2.1DBi and one of these.
CaptainBanana
Well-Known Member
I wonder how much loss is actually caused in the real world using these..
MrHorsepower
Member
Still have the problem of changing antennas for different gain/terrain...which was what the OP was aiming at ... I believe.
If you have 2 UHF's you need to set them up properly so they don't give audio feedback.
I use one with the primary or group channels and the other on full scan. But the second one doesn't scan the channels of the other UHF.
It's easier to swap antennas or just have a 4.5 - 6.5dbi one as you said in the 3rd or 4th post. That whole 'low gain for hills, medium gain for roads' thing has been blown out of proportion by GME and other antenna manufacturers IMHO. A 6.5dbi one will work just as well as a 2.1db in the mountains, actually better.