Notice: We request that you don't just set up a new account at this time if you are a previous user.
If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
Recovery:If you cannot access your old email address and don't remember your password, please click here to log a change of email address so you can do a password reset.

HAVE YOUR SAY. UHF CB to increase to 80 channels

General Tech Talk

Moderators: toaddog, TWISTY, V8Patrol, Moderators

Post Reply
Posts: 1253
Joined: Thu Dec 12, 2002 1:34 am
Location: QLD

HAVE YOUR SAY. UHF CB to increase to 80 channels

Post by Jeeps »

Hey guys, I posted this elsewhere but i thought i'd pop it on here too in case some aren't aware of it.

The ACMA which is the authority on the radio frequency spectrum is looking at changing most of the 400 mhz band to 12.5khz spacing from the current 25khz spacing. The ACMA acknowledges that the UHF CB band is the busiest part of the spectrum in australia and they are thinking about making some major changes to it to try and reduce congestion.

What this means is that there would be the availability to have a channel between each of the current 40 channels increasing the amount of channels to 80. This will definately not have any advantage in the country but in most built up areas every simplex channel is usually full and repeaters are full of idiots. If the channel allocation were to increase and the amount of repeater allocations were to double then there would be twice as many channels and repeaters and this would free up a lot of the garbage and traffic that clogs up the channels, and will clog up the channels in the future as more users get uhf cb's.

The ACMA has drawn up a Consulatation paper to seek feedback and submissions from people who use the CB band to see if we should keep it the same or increase the amount of channels. Link: ACMA - IFC 06/2008

6.1.2 UHF CITIZEN BAND—INCREASE IN AVAILABLE CHANNELS
The UHF Citizen Band (CB) comprises forty 25 kHz channels. Use of UHF CB is supported by a class licence. Anyone may operate UHF CB equipment provided that operation and the equipment used is in keeping with the conditions of the licence. Users do not have to apply for a licence and no fees are payable by CB radio users.

UHF CB equipment is cheap compared to typical land mobile equipment. Eight repeater channels are available, increasing the potential range of use to tens of kilometres. Australians are enthusiastic users of UHF CB for business and personal purposes. The main disadvantage to users is that no protection from interference is offered and therefore channels may be subject to congestion.
In light of the overall considerations in the band outlined in this paper, including the possibility of a reduction in channel bandwidth elsewhere in the band, it may be desirable to extend this potential bandwidth reduction to UHF CB. The existing 25 kHz channel bandwidth would be reduced to 12.5 kHz via an appropriate migration scheme.

For an environment such as UHF CB, where there is a very large quantity of existing equipment in use, a scheme where the old and new equipment have a degree of compatibility is desirable. This may suggest that the interleave method of yielding more channels could be the most appropriate.
If an 80 channel UHF CB band is to be implemented, ACMA anticipates that there would be a period of time during which existing equipment using 25 kHz bandwidth would be permitted to continue operation, and new 80 channel 12.5 kHz equipment would also be permitted to operate. After the phase-out date only the use of 12.5 kHz channel equipment would be authorised. Use of 25 kHz bandwidth UHF CB equipment would not be supported.
It is acknowledged that arrangements would need to be addressed to preserve the utility of the emergency channels throughout any transitional period.

18. ACMA seeks views on increasing the number of UHF CB channels from 40 to 80 by the implementation of 12.5 kHz channelisation, with a corresponding phase-out of 25 kHz channel equipment.
Yes, this means that eventually all current and old UHF CB radios would be non-compliant with new ones. Whether that's 5 or 10 years away who knows but most people who own GME and Icom and other commmercial grade radios will simply be able to get them reprogrammed. Others such as Uniden won't be so easy.

The contact info is at the link if you're like to have your say.


Anyway, i'm all for it. I think it's a top idea as there are sometimes never enough channels and always never enough repeaters for repeater jockeys :)

cheers
Posts: 216
Joined: Thu Mar 13, 2008 12:37 am
Location: Rockhampton

Post by Mr Sausage »

I wonder with the channels this much closer, would there be much splatter carried over? (I'm no radio techie!) But I remember back when AM was all the rage, we had terrible problems with it, particularly if a side band user was near by. Or one of the new flash truckies with the new (back then!) UHF would splatter the hell out of AM!

Just hope telstra don't get wind of this and start on the bandwagon of over-priced UHF sets as the old network gets made obsolete.... deja-vu!
94 J-top Paj, 07 V8 Commodore Wagon
77 Corvette, 06 Harley V-rod, 07 Suzuki M109R Boulevarde
Posts: 1415
Joined: Sat Oct 15, 2005 2:09 pm
Location: Trying to hide the bus keys!

Post by v6hilux »

Yep, the Bleed-over or splatter would be terrible, as many people know about using 25 Watts, illegally and the poor bugers on the receiving end, probably wont be using sub-tone to block it out!

Also the over-deviating truck drivers will cause splatter too :)
I'm the sharpest tool in the shed!
Posts: 1039
Joined: Mon Mar 05, 2007 10:28 am
Location: On board the Mothership

Post by Harb »

12.5 spacing is common in the rest of the radio world, So I can't see a problem.
Harb

http://www.4wdmonthly.com.au/shed/index.php?id=2244&im=1
Posts: 1254
Joined: Mon May 16, 2005 8:21 pm
Location: Sth Brissy

Post by LuxyBoy »

Doesn't STSS (i think it is called) already combat this. You know where you can select a channel and then a point within that channel so you can all go to channel 3.6 instead of just channel 3. Therefore in effect already having 400 channels (40x10)
Kind Regards,
Brad
Posts: 341
Joined: Wed Jun 13, 2007 9:45 pm
Location: Ipswich, Qld

Post by Micky-Lux »

Compatability between the 25khz equipment and the new 12.5khz equipment may be an issue though.

It may not be a good time at the moment to race out and buy a new UHF.
2000 SR-5 turbo diesel, dual airlockers, bit of a lift, some 15x8 sunnies, 32" bighorns, a few spotties, and a wireless, and a kiddie seat in the back.
Posts: 14668
Joined: Mon Aug 29, 2005 7:10 pm
Location: western shitney

Post by j-top paj »

if its 12.5khz then the 40 channels will still be there wont they? and just add "half channels"?
wont really affect me with my radio equipment :armsup:

i vote yeh do it
Banzy wrote:Dial up internet.........you'd post something and come back 2 beers later to see if it loaded.
my GU
Posts: 1836
Joined: Wed Aug 11, 2004 10:41 am
Location: Brisbane

Post by badger »

something like an ic400 wouldnt be effected by this would it? other than perhapse a little programming
1hd-fte 5 speed tiptronic 105 series
78 series troopy for work
gu ute play truck For sale
FTE 80 series sahara Sold

i think i have a problem
Posts: 14668
Joined: Mon Aug 29, 2005 7:10 pm
Location: western shitney

Post by j-top paj »

badger wrote:something like an ic400 wouldnt be effected by this would it? other than perhapse a little programming
reprogram the extra frequencies ;)
Banzy wrote:Dial up internet.........you'd post something and come back 2 beers later to see if it loaded.
my GU
Posts: 14187
Joined: Wed Apr 30, 2003 8:09 pm
Location: Trip Trip Trappin' across a bridge

Post by Goatse.AJ »

Cheaper radios will probably suffer from 12.5Khz spacing, mainly from lack of selectivity between channels. Not sure what the maximum deviation spec is under the current regs, probaly 5Khz? That may need to be tightened to 3Khz...
bru21 wrote:What happens in goat, stays in goat!
Posts: 379
Joined: Sat Aug 21, 2004 2:40 pm
Location: Epping , Vic

Post by BASSYK »

Mr Sausage wrote:I wonder with the channels this much closer, would there be much splatter carried over? (I'm no radio techie!) But I remember back when AM was all the rage, we had terrible problems with it, particularly if a side band user was near by. Or one of the new flash truckies with the new (back then!) UHF would splatter the hell out of AM!

Just hope telstra don't get wind of this and start on the bandwagon of over-priced UHF sets as the old network gets made obsolete.... deja-vu!
if youre getting splatter from 477Mhz to 27Mhz you have other problems to worry about
Gu TD42t

[url]http://www.3rdrock4x4.com[/url]
Posts: 70
Joined: Fri May 11, 2007 4:26 pm
Location: Central Coast, NSW

Post by Brainless »

I cannot see it phasing out older radios other then your old radio would then be channels

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79

this is only an assumption but as the freq rang itself isnt changing then i cannot see them not working entirely just you only get every second channel
87 Hilux SingleCab Project - 3rz, 35's 3inch Spring, 3 inch Body, GB Lift
88 Ford Mav, 4inch Spring, 3inch Body
Posts: 446
Joined: Wed Jan 02, 2008 8:50 am
Location: Mackay, Sunshine State

Post by clm434 »

Micky-Lux wrote:Compatability between the 25khz equipment and the new 12.5khz equipment may be an issue though.

It may not be a good time at the moment to race out and buy a new UHF.
just thought that myself
Posts: 14209
Joined: Sun Jan 11, 2004 11:36 am
Location: Adelaide

Post by -Scott- »

BASSYK wrote:
Mr Sausage wrote:I wonder with the channels this much closer, would there be much splatter carried over? (I'm no radio techie!) But I remember back when AM was all the rage, we had terrible problems with it, particularly if a side band user was near by. Or one of the new flash truckies with the new (back then!) UHF would splatter the hell out of AM!

Just hope telstra don't get wind of this and start on the bandwagon of over-priced UHF sets as the old network gets made obsolete.... deja-vu!
if youre getting splatter from 477Mhz to 27Mhz you have other problems to worry about
I was thinking something similar.
Posts: 151
Joined: Fri Apr 25, 2008 5:37 pm
Location: Sydney's North West... Near Richmond

Post by Tom0 »

LuxyBoy wrote:Doesn't STSS (i think it is called) already combat this. You know where you can select a channel and then a point within that channel so you can all go to channel 3.6 instead of just channel 3. Therefore in effect already having 400 channels (40x10)
CTCSS is just a squelching trick - it silences your radio until it 'hears' it's 'activate' code. The dude on the other end, his radio 'sends' the code before every transmit. Older radios will have Selcall, which was similar except you had to 'silence' your radio, then it would stay silent until someone sent your code, more like dialing a phone. Once it was un-silenced, it was open and you'd hear everything.

Both of these systems are "selective calling" - ie the just tell the radio to stay silent until it's told (with a code) to wake up/speak up - they don't actually add channels.
Posts: 2072
Joined: Sun Feb 11, 2007 4:50 pm
Location: Hobart

Post by macca81 »

Brainless wrote:I cannot see it phasing out older radios other then your old radio would then be channels

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79

this is only an assumption but as the freq rang itself isnt changing then i cannot see them not working entirely just you only get every second channel
this is how i see it...
[quote="Barnsey"]
Bronwyn Bishop does it for me.[/quote]
Posts: 1253
Joined: Thu Dec 12, 2002 1:34 am
Location: QLD

Post by Jeeps »

macca81 wrote:
Brainless wrote:I cannot see it phasing out older radios other then your old radio would then be channels

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79

this is only an assumption but as the freq rang itself isnt changing then i cannot see them not working entirely just you only get every second channel
this is how i see it...
However... in 5 years time if you are on ch1 in Narrowband 12.5khz and someone comes on with one of those old clunker GME 3200/3400 or uniden uh-015 radios which still uses 25khz and wideband, then your poor 12.5khz narrowband radio might get it's speaker blown to bits ;) (well not literally)

Moral of this thread, always buy icom - the radio of the future (literally) :)
Posts: 14209
Joined: Sun Jan 11, 2004 11:36 am
Location: Adelaide

Post by -Scott- »

Jeeps wrote:However... in 5 years time if you are on ch1 in Narrowband 12.5khz and someone comes on with one of those old clunker GME 3200/3400 or uniden uh-015 radios which still uses 25khz and wideband, then your poor 12.5khz narrowband radio might get it's speaker blown to bits ;) (well not literally)
UHF uses FM. It's been a while since I studied this stuff, but I believe FM uses bandwidth differently to AM, so a 25kHz FM signal won't necessarily stomp over a 12.5kHz neighbour like AM signals will.

We have some radio gurus here - anybody got any pics/charts/etc?
Posts: 1253
Joined: Thu Dec 12, 2002 1:34 am
Location: QLD

Post by Jeeps »

I believe it does but only in close proximity, just tested my base on 476.425 WB (current channel 1) and handheld on 476.4375 WB (possible future channel 2) and managed to get occasional interference from each other. However with both on NB it was fine and with the base changed over to the antenna on the other end of the house it was reduced significantly. There is probably a lot of overload to the base also from me sitting 2 metres from it keying up the handheld in the same room :)

I'm sure that the distance most cars would have while in convoy would be sufficient to stop the interference however.

cheers
Posts: 45
Joined: Thu Aug 21, 2003 2:46 pm
Location: Canberra

Post by grungle99 »

Jeeps wrote:
macca81 wrote:
Brainless wrote:I cannot see it phasing out older radios other then your old radio would then be channels

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79

this is only an assumption but as the freq rang itself isnt changing then i cannot see them not working entirely just you only get every second channel
this is how i see it...
However... in 5 years time if you are on ch1 in Narrowband 12.5khz and someone comes on with one of those old clunker GME 3200/3400 or uniden uh-015 radios which still uses 25khz and wideband, then your poor 12.5khz narrowband radio might get it's speaker blown to bits ;) (well not literally)

Moral of this thread, always buy icom - the radio of the future (literally) :)
Unfortunately it doesn't work that way, be it sometimes it appears like it, for analogue systems the Power Spectral Density is stronger per unit bandwidth for the narrow band option.

I was at the conference where they released the document, also invovled in the development of many of these types of documents and technical studies while I was employed at the regulator. The grandfathering period will be between 3 and 5 years for the older equipment unless the clubs respond to the discussion paper. This is the concern. 12.5 KHz channeling is a world wide standard in CBRS and Land Mobile arenas, including Police and emergency service equipment from around the world.

I started a thread earlier but will remove it as I was not aware of this thread. (Was in Melbourne at the conference...)

They will not listen to individual complaints etc, but a well approached array of club and "Grey Nomad" concerns will help the Transition period extend out to the 5 or 7 year mark.

G
Posts: 5179
Joined: Fri Dec 05, 2003 8:15 pm
Location: Brisbane Australia

Post by Shadow »

grungle99 wrote:
Jeeps wrote:
macca81 wrote:
Brainless wrote:I cannot see it phasing out older radios other then your old radio would then be channels

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65 67 69 71 73 75 77 79

this is only an assumption but as the freq rang itself isnt changing then i cannot see them not working entirely just you only get every second channel
this is how i see it...
However... in 5 years time if you are on ch1 in Narrowband 12.5khz and someone comes on with one of those old clunker GME 3200/3400 or uniden uh-015 radios which still uses 25khz and wideband, then your poor 12.5khz narrowband radio might get it's speaker blown to bits ;) (well not literally)

Moral of this thread, always buy icom - the radio of the future (literally) :)
Unfortunately it doesn't work that way, be it sometimes it appears like it, for analogue systems the Power Spectral Density is stronger per unit bandwidth for the narrow band option.

I was at the conference where they released the document, also invovled in the development of many of these types of documents and technical studies while I was employed at the regulator. The grandfathering period will be between 3 and 5 years for the older equipment unless the clubs respond to the discussion paper. This is the concern. 12.5 KHz channeling is a world wide standard in CBRS and Land Mobile arenas, including Police and emergency service equipment from around the world.

I started a thread earlier but will remove it as I was not aware of this thread. (Was in Melbourne at the conference...)

They will not listen to individual complaints etc, but a well approached array of club and "Grey Nomad" concerns will help the Transition period extend out to the 5 or 7 year mark.

G
yes, but just like AM CB radio sets, which were upgraded with upper and lower sidebands for every channel, the old sets still work, they just cannot access the upper and lower sidebands.

so from my understanding, the old radios will simply only be able to access channels 1 3 5 7 9 11 13 etc.

And if you want to talk to someone with an "old clunker" as someone put it, then you just pick on of those channels.

The newer radio's will effectively be transmitting at double the power? Assuming the transmision power is not reduced in line with the reduced bandwidth.
Posts: 14668
Joined: Mon Aug 29, 2005 7:10 pm
Location: western shitney

Post by j-top paj »

just buy quality equipment and you dont have to worry :cool:
Banzy wrote:Dial up internet.........you'd post something and come back 2 beers later to see if it loaded.
my GU
Posts: 2915
Joined: Tue Oct 05, 2004 11:29 am
Location: Sunshine Coast

Post by Bingham »

yes i dont think it will be a major issue........

ps my uhf aeriel and speaker for sale for a bargain at $150 think its 2 cheap and scaring people off so next week price goes up :!: give the consumers what they want :D

unit is sweet, just i have the boss buying me the faceless gme
2015 200 Series Gx TTD - ................ Fark 3L's -
Posts: 512
Joined: Sun Jul 01, 2007 6:04 pm
Location: cairns

Post by defmec »

so does this mean the cheap cb i bought of ebay (turns out it was from the u.s.)will work in aus
Posts: 14668
Joined: Mon Aug 29, 2005 7:10 pm
Location: western shitney

Post by j-top paj »

defmec wrote:so does this mean the cheap cb i bought of ebay (turns out it was from the u.s.)will work in aus
is it a FRS radio?
Banzy wrote:Dial up internet.........you'd post something and come back 2 beers later to see if it loaded.
my GU
Posts: 1413
Joined: Mon Aug 21, 2006 5:54 pm
Location: Perth

Post by Moph »

Any more news on this? I'm looking at buying a GME TX3440 which has 25MHz channel spacing TX/RX but only RX on 12.5MHz.

Don't want to splash the cash if it's going to be useless in a few years time.....

Not keen on spending an extra couple of hundred to get a comparable Icom if its not necessary.
Posts: 3278
Joined: Mon Mar 03, 2003 9:03 pm
Location: St Helena, Melbourne.

Post by Loanrangie »

Moph wrote:Any more news on this? I'm looking at buying a GME TX3440 which has 25MHz channel spacing TX/RX but only RX on 12.5MHz.

Don't want to splash the cash if it's going to be useless in a few years time.....

Not keen on spending an extra couple of hundred to get a comparable Icom if its not necessary.
Call GME and ask if it will be possible to re program it ?
Saddle up tonto, its the not so loanrangie! . 98 TDI DISCO lightly modded with more to come.
Post Reply

Who is online

Users browsing this forum: No registered users and 114 guests