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Posted: Thu Nov 08, 2007 10:55 am
by j-top paj
1-8 really shouldnt be used for simplex communications.
the "dup" or "duplex" button is for the "range extender" feature of your radio.
when transmitting on a channel between 1-8 in duplex mode, your radio is actually transmitting on 31-38. as soon as you let go of the PTT button the radio will go back to receiving on channels 1-8.
eg. using ch1 duplex will transmit on ch31 and then receive on ch1 again.
when your using a repeater, your signal will be received by the repeater (usually on top of a mountain somewhere that it has good line of sight over the surrounding areas) and then retransmitted with a better signal to give you more coverage.
basically if your on one side of a mountain and your mate is on the other, you wont be able to communicate directly so you use the repeater.

the problem is when someone uses say ch31 because they think it is a clear channel and cant hear anyone they are actually being retransmitted on ch1 (if there is a repeater that can receive the signal. and you would be supprised how far your signal will go. you may not be keying it up continually, but still enough to be irritating)

another example. on the weekend at nissan trials i noticed there were some people using ch33 and intermitantly keying up the ch3 repeater at appin.
and the suzuki club using ch1 simplex when the ch1 repeater could be clearly heard at the same time.

ch5/35 are also used for EMERGENCYS ONLY. and there are people that do moniter these channels.
CREST is one organisation that does.

as for 22/23 ausoops has explained that one.

ch40 is set aside as the "road channel" but the truck drivers have decided that one channel isnt enough so they use 29 also.
and also in sydney its a common problem when they start on 40, hear a mate and say "go down one mate" until they find a clear channel. most of the time ending up on 37 or 35 :roll:

Posted: Thu Nov 08, 2007 2:22 pm
by vSAHARAx
So say for example, when on a road trip and have a little convoy going to talk to the car infront really you should only use channels 9-21, 24-30??? Is this correct?

Im buying a GME TX 3420 in the next week or so, will be interesting to see if there is any of this information in the manual!!!

Very very interesting. will save this thread as a favorite so i can come back to it and use it as a reference :P

Troy

Posted: Thu Nov 08, 2007 3:12 pm
by gumtree
thats sounds about right to me. 2 make it easy for me to remember i will just use channels 10-20 and everything should be ooooook.

so is it ok if we use ch1-8 on duplex if cant hear out mates on the other side of the mountain. it sounds like we should only use these channels if we really need to. am i right?

Posted: Thu Nov 08, 2007 4:38 pm
by ausoops
vSAHARAx wrote:So say for example, when on a road trip and have a little convoy going to talk to the car infront really you should only use channels 9-21, 24-30??? Is this correct?

Im buying a GME TX 3420 in the next week or so, will be interesting to see if there is any of this information in the manual!!!

Very very interesting. will save this thread as a favorite so i can come back to it and use it as a reference :P

Troy
when i bought mine it was in the manual. (tx3200)

Posted: Thu Nov 08, 2007 7:35 pm
by j-top paj
vSAHARAx wrote:So say for example, when on a road trip and have a little convoy going to talk to the car infront really you should only use channels 9-21, 24-30??? Is this correct?
basically,
you can also use 39 and 40 if u want but if theres little children in the car id advise not to. especially not 40.
but yeh for convoy work 9-21 24-30 is the way to go.
also i think 18 is the caravaners channel so if your towing a van maybe use that one if you want to chat to other caravaners

Posted: Thu Nov 08, 2007 8:19 pm
by longlux
Continuous Tone Coded Squelch System (CTCSS) is handy if your in a group & you don't want to listen to others on the same channel.

Posted: Fri Nov 09, 2007 12:21 am
by j-top paj
longlux wrote:Continuous Tone Coded Squelch System (CTCSS) is handy if your in a group & you don't want to listen to others on the same channel.
dont start talking about ctcss/dcs etc... that will just confuse everyone :lol:

Posted: Fri Nov 09, 2007 6:39 am
by psycronic
gumtree wrote:so is it ok if we use ch1-8 on duplex if cant hear out mates on the other side of the mountain. it sounds like we should only use these channels if we really need to. am i right?
not really correct, if there is a repeater in the area then yes that should work to talk to your mate on the other side of the mountain.

Not all of the repeater channels have repeaters on them in all areas

http://www.tropinet.com/uhf-repeaters/



Notes on channel allocations:

1. Several channels are set aside for special uses. These are:

Channel 5 Emergency Channel - don't use this channel for comms, I have my group scan setup to include this channel though

Channel 11 Call Channel

Channel 40 Road Channel

2. Channels 22 and 23 are used for telemetry and remote control purposed. The ACMA advises that voice communications on these channels is prohibited.

3. Repeaters transmit between channels 1-8 and receive between channels 31 and 38. Avoid these channels for non-repeater (simplex) communications. Repeaters operating on Channel 5/35 may be used for emergency communication only. If you are near the station you are talking to, you should move from the repeater to a simplex channel (see note 5) to leave the repeater free for others who cannot communicate direct.

4. Though Channel 11 is officially the call channel, most people use repeaters for this purpose instead. Many truck drivers use Channel 40.

5. The following channels are suggested for general simplex communication: 9, 10, 12-21, 23-30, 39.

and I think it is channel 18 that caravaners have declared as there unofficial channel