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jx2mad
11th November 2010, 12:47 PM
With the start of the new channel structure will it be legal to still use older 40 ch. sets or will their channel bandwidth be too great? Jim

one_iota
11th November 2010, 01:52 PM
Yes it will still be legal and the current sets will still work on the existing 40 channels. The new additional 40 channels are being "slotted" in between the existing frequencies.

From this useful site: UHF CB Australia - News - Repeater Locations - History - Sales & More (http://www.uhfcb.com.au/UHF-CB-Changes.php)



Frequently Asked Questions


Will my old UHF CB radio still work when the changes take place?

Yes, You existing UHF CB radio will still work after January 1st 2011

Will my old UHF CB radio interfere with other channels?

It is possible that old UHF CB will interfere with new channels but you would need to be very close to another radio to create a problem

Can I talk to someone on a new UHF CB radio with my old UHF CB radio?

Yes, You will be able to talk to another person using a new UHF CB radio provided they are on one of the current 40 channels, if the other UHF CB radio is on one of the newly allocated channels then you will not be able to talk to them

Will I notice any changes when talking on a new UHF CB radio with my old UHF CB radio?

Yes, You will notice that the sound will be distorted but you will be able to talk to each other

KarlB
11th November 2010, 02:37 PM
It is my understanding that the use of the 'current' 40 channel units will not be supported beyond 5 years and after that their use will be illegal. Also, because of the narrower channel spacing the 'signal energy' will be significantly less and the end user will perceive this as lower volume (ie you will have to turn the sound up).

Cheers
KarlB
:)

miky
15th November 2010, 08:34 PM
It is my understanding that the use of the 'current' 40 channel units will not be supported beyond 5 years and after that their use will be illegal. Also, because of the narrower channel spacing the 'signal energy' will be significantly less and the end user will perceive this as lower volume (ie you will have to turn the sound up).

Cheers
KarlB
:)

And the source of this "understanding" is?


.

KarlB
15th November 2010, 09:09 PM
And the source of this "understanding" is?
.

Here is the link to the draft standard: http://www.acma.gov.au/webwr/_assets/main/lib311942/ifc23-2010_rcomms_uhf_cb_radio_equipment_standard_2010.p df .You will see, pursuant to s7, that after 1 Jan 2016, older equipment will be deemed to be noncompliant. Also, all new equipment sold 6 months after the new standard comes into force must be compliant with the new standard. The standard is still a draft and there may be changes, but I wouldn't bet on it. I have seen nothing to suggest that it will not commence on 1 Jan 2011, as indicated in the draft.

Cheers
KarlB
:)

miky
16th November 2010, 08:23 AM
Thanks for the link. Just what I was after.


.

Sprint
16th November 2010, 11:25 PM
i'm yet to see a valid argument for changing the existing setup

Hamish71
17th November 2010, 02:49 PM
It doesnt really matter, does it. if you need a radio to use now, then pretty much you are stuck with a 40 channel set up.

At some stage in the future though, this set up will be redundant, and you will need to replace it.

So, do you really need one?....or can you wait?

miky
17th November 2010, 03:04 PM
Perhaps the question to ask your supplier is: can the radio be programmed for the new channels?

For what it is worth... the Icom 400Pro can. I have a 400Pro.
As far as I can see the Icom 440 can't. I don't have one.
Looks like the GME 36xx and 38xx radios can. I have a 3840.

If any one can provide a list of radios that can be programmed it would be good.
Also, when will the "new" radios become available?


.

KarlB
17th November 2010, 03:26 PM
I would be highly surprised if the major manufacturers are not poised for the release of new models and are just waiting for the finalisation/release of the of the new standard by ACMA. They will be holding back a little, hoping to get rid of old stock I suspect, but as soon as one of them makes a significant move, the rest will quickly follow. Unless something falls over with ACMA, the market will see all the new models in the first quarter of 2011, I am sure. I am holding off.

Cheers
KarlB
:)

Hamish71
17th November 2010, 05:48 PM
Perhaps the question to ask your supplier is: can the radio be programmed for the new channels?

For what it is worth... the Icom 400Pro can. I have a 400Pro.
As far as I can see the Icom 440 can't. I don't have one.
Looks like the GME 36xx and 38xx radios can. I have a 3840.

If any one can provide a list of radios that can be programmed it would be good.
Also, when will the "new" radios become available?


.

I spoke to GME a couple of months ago. I was told, none of their product can, and they dont plan on doing any design on this until after the new specification is nailed down....think I have an email from them somewhere, will see if i can find it.

101RRS
17th November 2010, 05:59 PM
I did read somewhere in the draft policy that it will be illegal for manufacturers to sell new 40 channel UHF radios three months after the new channels come in.

Lotz-A-Landies
17th November 2010, 06:16 PM
Garry

Submissions to the inquiry only closed on October 12th just gone, so it is unlikely that any legislation/regulation on the sale of legacy equipment will yet have been gazetted.

The old equipment will still be usable although 40 channel equipment will cause interference to 80 channel reception when they are on frequencies that are overlapped by the broad bandwidth 40 ch sets. There will also be some clipping of the audio reception, not too dissimilar to that which occurs on telephones.

My advice, don't rush in to any new equipment yet and there are likely to be a few bargains on 40 ch sets in the near future.

Diana

KarlB
17th November 2010, 06:33 PM
I did read somewhere in the draft policy that it will be illegal for manufacturers to sell new 40 channel UHF radios three months after the new channels come in.
Illegal to sell them after 6 months; and illegal to use them after 5 years.

Cheers
KarlB
:)

Lotz-A-Landies
17th November 2010, 08:49 PM
Illegal to sell them after 6 months; and illegal to use them after 5 years.

Cheers
KarlB
:)Where is the radio buy-back? They had one for guns, we should be demanding one for the radios!

At least with the changeover from analog (was still the best phone in the bush) to GSM/CDMA you could get a new basic handset for free!

KarlB
17th November 2010, 09:06 PM
Where is the radio buy-back? They had one for guns, we should be demanding one for the radios!

At least with the changeover from analog (was still the best phone in the bush) to GSM/CDMA you could get a new basic handset for free!

I suspect the depreciated value after 5 years would be zero. And as for free mobile handsets ...? The cost would simply have been loaded onto other charges. The gun buyback was funded by a 1% levy on income tax. As is often said: "there is no such thing as a free lunch"!

Maybe you should write a letter to Minster Stephen Conroy or Shadow Minister Malcolm Turnbull. I am sure they would both be interested in your proposition. You could also copy it to the PM and Tony Abbott. The latter is 'already all ears'.

Cheers
KarlB
:D

Fluids
17th November 2010, 09:14 PM
It doesnt really matter, does it. if you need a radio to use now, then pretty much you are stuck with a 40 channel set up.

At some stage in the future though, this set up will be redundant, and you will need to replace it.

So, do you really need one?....or can you wait?


Or use one of these (handheld) if you need one now, and wait till the in car sets are out. Bet they won't be cheap when they hit the streets.

128 user programmable channels vhf/uhf 136-174mhz/420-450mz 5w/4w
accessories & batteries are cheap ... about $16 for a battery!

Programmable from your PC for 40ch or the new 80ch uhf system with channels to spare ! :)

Two Way Radio KG-UVD1 (http://www.wouxun.com/Two-Way-Radio/KG-UVD1P.htm)

Get it from here (i did + accessories)
1x KG-UVD1P UU TX 136-174/420-520Mhz Dual Band - 409Shopwww.409shop.com 409 ??? ??? KG-UVD1 VX-8R VX-3R VX-7R VX-170 KG-699E KG-669 KG-689 PX-777 PX-888 FT-897 FT-857 VX-177 VXA-300 KG-679 VEV-3288S V-1000 TG-UV FT-817ND FT-60R FT-897 FT- (http://www.409shop.com/409shop_product.php?id=104056)
$110US delivered

or here
WOUXUN KG-UVD1P 136-174/420-520Mhz+Earp+usb cable (eBay item 110604368474 end time 27-Nov-10 15:41:09 AEDST) : Electronics (http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=110604368474)
$110US + postage (about $12)

It's alot of radio for the money, works extremley well, and it's inexpensive (not cheap!)

rovers4
17th November 2010, 10:45 PM
The use of frequencies outside the UHF CB band can only be done if you have a licence to do so. A yearly fee in the $hundreds, or if you a an amateur and have passed an exam and still pay money for the privilige.

Rovers4.

Hoges
17th November 2010, 10:51 PM
I recently bought a GME3400 from a reputable supplier in Bris. I needed it for a big trip and raised the issue... he was emphatic that he had been assured by GME they (dealers) would be able to reprogram the GME3400 in due course once the Feds had Gazetted the new rules. I was under the impression that public consultations have only recently concluded... and we know what the PS is like..."...they also serve who sit and wait..." :eek::wasntme:

LowRanger
17th November 2010, 11:41 PM
It is my understanding that the use of the 'current' 40 channel units will not be supported beyond 5 years and after that their use will be illegal. Also, because of the narrower channel spacing the 'signal energy' will be significantly less and the end user will perceive this as lower volume (ie you will have to turn the sound up).

Cheers
KarlB
:)


There will be NO perceived lower volume problem.All the new radios will just have a better IF filter that will allow operation at the 12.5 KHz channel spacing compared to the 25KHz spacing now

Wayne

LowRanger
17th November 2010, 11:50 PM
Garry

Submissions to the inquiry only closed on October 12th just gone, so it is unlikely that any legislation/regulation on the sale of legacy equipment will yet have been gazetted.

The old equipment will still be usable although 40 channel equipment will cause interference to 80 channel reception when they are on frequencies that are overlapped by the broad bandwidth 40 ch sets. There will also be some clipping of the audio reception, not too dissimilar to that which occurs on telephones.

My advice, don't rush in to any new equipment yet and there are likely to be a few bargains on 40 ch sets in the near future.

Diana


You may get intermodulation,if someone in on an adjacent channel and is very local to you,and your radio is one of the older types.Any of the later models,should have good enough IF filters to filter just about all but the strongest or dirtiest signals.And you won't notice any clipping of the audio.I have been using adjacent frequency operation on different bands for nearly 40 years,and at 5 watts output,you won't have a problem,unless someone has been fiddling inside the radio.

Wayne

miky
18th November 2010, 10:53 AM
I spoke to GME a couple of months ago. I was told, none of their product can, and they dont plan on doing any design on this until after the new specification is nailed down....think I have an email from them somewhere, will see if i can find it.


I guess it depends on the model.
Many of them are programmable like the 3840 that I use. I use it for CB at 5W (of course) and commercial frequencies at 25W.

The program does 36xx and 38xx radios.



.

FFR
28th November 2010, 08:51 AM
There will be NO perceived lower volume problem.All the new radios will just have a better IF filter that will allow operation at the 12.5 KHz channel spacing compared to the 25KHz spacing now

Wayne

Hi Wayne,

Narrow Band radios (12k5 step) employ smaller FM deviation than the Wide Band (25k step) radios. A 12k5 transmission, when received with a 25k radio, is heard with a lower audio than a genuine 25k transmission due to its smaller spectrum occupancy. On the other hand, a 25k transmission, when received with a 12k5 radio, is heard with excessive audio level, up to the point that audio peaks used to be clipped.

There are some amateur radios in the market where you can select NB or WB FM in UHF (nothing to do with the WB filter for FM broadcast) so both RX and TX bandwidh are tuned to match the kind of service that you want to exploit.

miky
28th November 2010, 03:39 PM
Hi Wayne,

There are some amateur radios in the market where you can select NB or WB FM in UHF (nothing to do with the WB filter for FM broadcast) so both RX and TX bandwidh are tuned to match the kind of service that you want to exploit.

As per my post above, GME also have that option for each channel.


.

LowRanger
28th November 2010, 03:55 PM
Hi Wayne,

Narrow Band radios (12k5 step) employ smaller FM deviation than the Wide Band (25k step) radios. A 12k5 transmission, when received with a 25k radio, is heard with a lower audio than a genuine 25k transmission due to its smaller spectrum occupancy. On the other hand, a 25k transmission, when received with a 12k5 radio, is heard with excessive audio level, up to the point that audio peaks used to be clipped.

There are some amateur radios in the market where you can select NB or WB FM in UHF (nothing to do with the WB filter for FM broadcast) so both RX and TX bandwidh are tuned to match the kind of service that you want to exploit.

The 25KHz and 12.5KHz does not represent the width of the transmission.It is the spacing in KHz between the allocated channels.If you had a radio transmittting a signal that wide,the emitted spurious emissions would not meet FCC or Aust.Standards.

Wayne

FFR
30th November 2010, 07:20 AM
The 25KHz and 12.5KHz does not represent the width of the transmission.It is the spacing in KHz between the allocated channels.If you had a radio transmittting a signal that wide,the emitted spurious emissions would not meet FCC or Aust.Standards.

Wayne

Yes,

in the first line I named the NB radios as the UHF-CB having 12k5 step, and WB radios as the UHF-CB having 25k step. You'll agree with me that actual spectrum occupancy figures exceeds the scope of this forum.


On the other hand, in order to make my kenwood inter-operable between the old and new standards, I plan to reprogram it like:

1 WB (old)
1 NB (new)
2 WB (old)
2 NB (new)
.
.
.
41 NB (new)
42 NB (new)
43 NB (new)
.
.
.
80 NB (new)

... although it will take some time until I have the opportunity to test it...

Do you know if there is some amateur on-line receiver at Sydney area to experiment with?

Cheers,

Carlos

LowRanger
30th November 2010, 05:35 PM
Ahhhh I see what you are talking about now.You are talking about intermodulation.Where the signal transmitted on channel 1 (476.425) and recieved on the to be new channel 2 (476.4375) will be attenuated.I was talking about 2 radios of different types old (25KHz) and new (12.5KHz) transmitting and receiving on the same frequency,will not be attenuated.

I already have my Alinco handheld programmed,as I don't have it set as channels as such.Just set up to transmit and receive in 12.5KHz steps between 476.425 and 477.400.

And yes,this is probably not the forum to go into the technicalities,rather just the usability of the products.

Wayne