Northern & Western are nearly always 'patched'. I've seen it become unpatched if there is a big job on in one of the Districts and ESTA have an operator to man the channels seperately.
Appliances in each of these Districts still use their allocated TGID's (Channels) and don't see any difference, those being;
Ch.02 Northern (TGID 10001)
Ch.04 Western (TGID 10003)
I believe what happens from my own observations is given they're patched what shows on your scanner will depend on what Channel is classed as the 'parent' and what is the 'tag along' so too speak. I know very un-technical terms, but it helps with the explanation.
Example:
If Northern has Western 'patched' to it then you'll see the Northern TGID as it will be classed as the parent.
If Western has Northern 'patched' to it then you'll see the Western TGID as it will be classed as the parent.
As for:
Ch.01 Central (TGID 10000)
Ch.03 Southern (TGID 10002)
Ch.05 Eastern (TGID 10004)
Channels 03 and 05 are the same as the example above.
Ch.01 runs solo of a day, however of an evening it should be patched to Ch.03 and 05 from about 6pm I think it was. Possibly also weekends.
Patch times can vary depending on staffing levels at ESTA, workloads and incidents, so it's not always the rule.
http://vicradiozone.wordpress.com/fire/ ... e-brigade/
Hope that helps.
