The best transmitting location isnt always the most sensible place on your vehicle. Ideally, the centre of the roof is the best position for an antenna, but this obviously causes issues with mounting, clearance, and the fitment of your roof rack.
This is why youll often see antennas mounted on the bullbar of a 4WD. But unfortunately, this has issues of its own. The signal path is obstructed by the vehicle and therefore cannot transmit evenly behind the vehicle. The signal path may also be obstructed in a forward direction by other vehicles travelling in front of you.
For this reason, a bullbar-mounted antenna will never truly allow your UHF radio to be used to its full potential even if its tall enough to clear the height of your roof.
Bulldozer said
06:31 PM Apr 23, 2023
Warren-Pat_01 wrote:
Hi Bulldozer, It is preferable that the antenna is vertical for maximum transmission, receiving distance. Have a look at radiation patterns for aerials & you'll see why. However you may still get some reception, but over a shorter distance with the aerial horizontal - try it, perhaps with the assistance of a friend who has a set installed in his car & see how you fare.
Thank you.
Wazza.
TimTim said
09:18 AM Apr 24, 2023
Thank you all for your contributions as I was contemplating a CB radio for when I and two other vans travel north to Cape York. I see that some companies are selling two antenna packs so that you can change over depending on the terrain that you travelling on and was wondering whether this was worthwhile.
Also, with having to wear hearing aids do people experience any problems?
The antenna should (must?) be vertical and as far away as reasonable possible from the microphone and radio. The ideal place in a vehicle is in the middle of the roof, failing that anywhere with a bit of metal directly underneath is good - a front wing perhaps?
Bulldozer said
01:53 PM Apr 24, 2023
Thanks Mike, mine is a 5w hand held, only need it for car to car / truck ect, you hear a lot of folks throw them on the seat, cup holders ect. I didn't think it would make a lot of difference. I was picking up a couple of codgers talking on ch 40 this morning it was quite clear. My car was in the garage. The main rd is about 1k away. my uhf was on the dash with antenna 20 deg pointing up, having a clear view of the windscreen front and rear. so I don't know if glass is a hinderance ?
Mike Harding said
02:02 PM Apr 24, 2023
If you only need car-to-car, say 200m, then almost anything will do as an antenna.
TimTim said
03:04 PM Apr 24, 2023
Thank you Mike I knew you would respond as you are very knowledgable on the subject .
Will do a bonnet mount as I do not have a bull bar.
Cheers
-- Edited by TimTim on Monday 24th of April 2023 03:14:39 PM
Bulldozer said
03:45 PM Apr 24, 2023
Mike Harding wrote:
If you only need car-to-car, say 200m, then almost anything will do as an antenna.
Thanks Mike! Thats what I wanted to hear.
Cheers Wazza.
-- Edited by Bulldozer on Monday 24th of April 2023 03:46:58 PM
The best transmitting location isnt always the most sensible place on your vehicle. Ideally, the centre of the roof is the best position for an antenna, but this obviously causes issues with mounting, clearance, and the fitment of your roof rack.
This is why youll often see antennas mounted on the bullbar of a 4WD. But unfortunately, this has issues of its own. The signal path is obstructed by the vehicle and therefore cannot transmit evenly behind the vehicle. The signal path may also be obstructed in a forward direction by other vehicles travelling in front of you.
For this reason, a bullbar-mounted antenna will never truly allow your UHF radio to be used to its full potential even if its tall enough to clear the height of your roof.
Thank you.
Wazza.
Thank you all for your contributions as I was contemplating a CB radio for when I and two other vans travel north to Cape York. I see that some companies are selling two antenna packs so that you can change over depending on the terrain that you travelling on and was wondering whether this was worthwhile.
Also, with having to wear hearing aids do people experience any problems?
Cheers
Tim
Tim Tim: you may find this thread helpful:
Antenna gain
----
Bulldozer:
The antenna should (must?) be vertical and as far away as reasonable possible from the microphone and radio. The ideal place in a vehicle is in the middle of the roof, failing that anywhere with a bit of metal directly underneath is good - a front wing perhaps?
If you only need car-to-car, say 200m, then almost anything will do as an antenna.
Thank you Mike I knew you would respond as you are very knowledgable on the subject .
Will do a bonnet mount as I do not have a bull bar.
Cheers
-- Edited by TimTim on Monday 24th of April 2023 03:14:39 PM
Thanks Mike! Thats what I wanted to hear.
Cheers Wazza.
-- Edited by Bulldozer on Monday 24th of April 2023 03:46:58 PM