Allocation of a subtone in analogue radios

[freqwaves]

I was under the impression that when you are allocated a new analogue frequency license from the ACMA that they also allocate you a subtone. I thought this would be important in case the same frequency is also being used in the area & you don't end up on the same subtone. But from what I have found out it's more a hit & miss with some now choosing to pick a subtone in the DCS range to avoid a clash. The other way to check is to do a frequency search on the ACMA to see if the frequency assigned is used in the area or close by or by doing a onsite area check.
Any other radio programmers can give some feedback on this?

Thanks, John.

[rustynswrail]

I was under the impression that when you are allocated a new analogue frequency license from the ACMA that they also allocate you a subtone. I thought this would be important in case the same frequency is also being used in the area & you don't end up on the same subtone. But from what I have found out it's more a hit & miss with some now choosing to pick a subtone in the DCS range to avoid a clash. The other way to check is to do a frequency search on the ACMA to see if the frequency assigned is used in the area or close by or by doing a onsite area check.
Any other radio programmers can give some feedback on this? Thanks, John.

John,

The allocation of CTCSS and DCS is purely down to the programmer. ACMA have nothing to do with subtone on analog systems, or any protect tone for any system for that matter. To avoid possible conflict avoid tones like 103.5, 107.2, 123.0, 136.5 and 173.8 to name but a few. The higher tones seem to be less used than the lower. Also avoid adjacent tones where possible. I would suggest using DCS where possible. More options and less chance of conflict.

Again if you need help give me a ring.

Russell

[Bigfella237]

It'd be great if CTCSS, DCS and even NACs were recorded against the frequency assignments on the ACMA database, it would save a lot of time hunting them out with a scanner but it would add a lot of complexity to the ACMA listings, you could well have the same frequency on the same site listed multiple times with different tones.

Andrew

[freqwaves]

Thanks for the feedback guys, will go for the higher tones next time I do a new analogue system.

John.