whats the difference?

mroffroader · Post by **mroffroader** » Mon Nov 13, 2006 5:16 pm

is a UHF radio the same as a PRS? i want a truck mounted PRS but it looks as if a PRS is a UHF?????????

someone help me :roll:

mroffroader · Post by **mroffroader** » Mon Nov 13, 2006 5:17 pm

oops put this in the totally wrong section :roll:

turoa · Post by **turoa** » Mon Nov 13, 2006 5:18 pm

You're an idiot. Putting it in the wrong section

I think they are different radios though. What you want is a UHF PRS. I think CCVC uses VHF?

They stand for Ultra high frequency and
Very high frequency

brianr70 · Post by **brianr70** » Mon Nov 13, 2006 5:20 pm

see this months 4x4 action mag, has good article in tech section regarding PRS and CB

mroffroader · Post by **mroffroader** » Mon Nov 13, 2006 6:00 pm

i dont want a CB, i want a PRS but cant find any cheap ones but UHF are cheap and there like the same thing?

turoa · Post by **turoa** » Mon Nov 13, 2006 6:17 pm

NO, THEY ARENT THE SAME THING

PRS is different, brian70r was just telling you that there's information about prs's and CB's in the lastest 4x4 action. Not telling you that you should buy one. I will read it and post the gist here later tonight (if no on beats me too it :wink:

)

mroffroader · Post by **mroffroader** » Mon Nov 13, 2006 6:25 pm

turoa wrote:NO, THEY ARENT THE SAME THING

PRS is different, brian70r was just telling you that there's information about prs's and CB's in the lastest 4x4 action. Not telling you that you should buy one. I will read it and post the gist here later tonight (if no on beats me too it )

oooohhhhh there not? haha ok thatl be good

icekayak · Post by **icekayak** » Mon Nov 13, 2006 6:36 pm

Ok as far as i understand it:

PRS = Personal Radio Service = A freqencey band set aside for public personal radio use, free to use. = 476mhz +-2 UHF and i belive it is limited to 25w power output. (could be 5w though)
UHF = Ultra High Frequencey
VHF = Very High Frequencey
CB = Citizen Band = 27mhz AM
Marine Radios are VHF

There is also HF SSB which have a much better range but are more $$$

All PRS radios work on the UHF Frequencey Band.
All UHF radios are not PRS (but many 'home' ones will talk to each other)

But these days people are referring to prs as cb now just to confuse people even more....

Overseas in US they have FRS and ?GRMS? which is the same idea as PRS but i believe are not legal to use in new zealand, and won't talk to PRS radios...

Chances are if its a 40 channel UHF it will work with PRS

icekayak · Post by **icekayak** » Mon Nov 13, 2006 6:39 pm

ok if you wanna get more techincal...

27MHz CB
This system utilises 40 channels in the High Frequency (HF) range, which covers 26.965Mhz to 27.405MHz. These CBs use Amplitude Modulation (AM) and they usually come with upper and lower sideband (SSB) which helps increase range and performance. AM and SSB are not compatible with one another and for this reason the AM mode is encouraged to be used on channels 1 to 14 and the SSB mode on channels 15 to 40. AM signals can sometimes be fairly noisy and distances can vary from 5km to 10km in normal conditions. When SSB is used on a channel, distances between 15km and 50km can be obtained.

UHF CB
This system utilises 40 channels in the Ultra High Frequency (UHF) range, which covers 476.425MHz to 477.400MHz. These CBs use Frequency Modulation (FM) and have become the preferred mode of operation for many. Since UHF signals travel in a straight line, the terrain plays an important part in how well the signal is transmitted or received. For example, the transmission will perform quite poorly if the signal is blocked by hilly or heavily forested areas. On flat terrains such as open countryside, distances between 5 and 20km may be achieved. Distances of up to 100km can be achieved if one or both UHF CB units are elevated on say a hilltop. UHF signals are less prone to power line noises and can also provide clear and crisp communications without the long distance interference which is evident on 27MHz signals. UHF CBs can utilise a repeater station that retransmits the signals onto another channel. This can provide much further coverage and can be handy when you are out in the bush and you want to scan and talk to other fellow trekkers.

http://www.exploroz.com/Vehicle/Accessories/UHFRadio.aspx

icekayak · Post by **icekayak** » Mon Nov 13, 2006 6:42 pm

Also:http://zcat.wired.net.nz/radio/about/

The Citizen Radio Service was established to meet the need for a short range means of communication for personal or business use which could not be economically or practicably met by other communication services, and has existed in New Zealand since 1953, being one of the first of this type in the world.

Originally only 1 channel (26.500 MHZ) was available with a power limit of 0.5 watts. In 1963 the number channels were increased to 7, all in the 26 MHZ frequency band. 1966 the number of channels was further increased to 11 channels for general use and 3 for Government, including approved businesses and persons. Power increased to 2 Watts.

Proposals to extend the Citizen Band service were released to the public in June 1987 and from the resulting submissions, changes were made. Details of the new 40 channel service was announced by Dr Cullen at the June 1988 annual conference of the Citizen Band Radio Association of New Zealand, coming into effect 1 July 1988. October 1988, any type of aerials were allowed, including beams.

1993 the Radio Frequency Service requested CBRANZ to forward a submission for a PRS Citizen Radio Service (UHF CB). CBRANZ forwarded a submission based on its 1978 submission sent to Post Office Communications for a UHF CB Citizen Service in addition to the then AM CB. 1 July 1994, Personal Radio Service in the 476 - 477 MHZ UHF frequencies extended the Citizen Radio Service. Introduction of PRS was to improve options to the general public to provide an economical radio service for small users in remote areas not already covered by other systems. Possible use includes sporting and community events, small businesses and hobby activities. Repeaters also allowed on the PRS service but require a separate licence.

So that the services may be freely utilised, regulatory requirements have been kept to the minimum and no operator qualifications deemed necessary.

Sorry about all the writing

icekayak · Post by **icekayak** » Mon Nov 13, 2006 6:49 pm

oh and a trunking or trunked UHF radio is something different again (sorta) basically its like what the ambulance use and you can transmit short data messages over it also, like when you arrive on scene you push a button, when you leave you push another, when you arrive at hospital you push another.. that way the control centre knows your status the whole time etc etc...

but basically its no use to you (small chance it would be on the prs frequencey but probably more hassle than its worth)

mroffroader · Post by **mroffroader** » Mon Nov 13, 2006 7:12 pm

lol yea thats what i wanted to know if a 40 UHF will work as a PRS radio eg. http://www.trademe.co.nz/Electronics-ph ... 255904.htm

as he says PRS but then say 40 channel UHF

icekayak · Post by **icekayak** » Mon Nov 13, 2006 7:21 pm

Price is a bit high, but yeh that's what you want

I paid $150 From memory for an older uniden one, which i thought was a reasonable price at the time

If i was gettin one at a 'new' price personally i would get one with the satelite faceplate like this sorta thing: so the faceplate can be mounted separately

There's also these:
http://www.trademe.co.nz/Electronics-photography/GPS/GPS-units/auction-77116846.htm

mroffroader · Post by **mroffroader** » Mon Nov 13, 2006 7:24 pm

icekayak wrote:Price is a bit high, but yeh that's what you want
I paid $150 From memory for an older uniden one

yea was just an example :wink:

$150!!!!!!!!! where from? that what i want and at that price