Question: Maximum users per channel

[judoka]

I vaguely remember that there is a Federal guideline for the maximum number of users per channel. Does anyone have a reference ?
I suspect that it might apply to trunked systems rather than conventional but I could do with numbers for both types.
If there isn't a definitive answer, does anyone have a rule of thumb?

Thanks

[RKG]

Look in Sub-part L (T band).

[Jim202]

I think your research will provide that there is a minimum not max for channel loading on a trunked system.

Jim

I vaguely remember that there is a Federal guideline for the maximum number of users per channel. Does anyone have a reference ?
I suspect that it might apply to trunked systems rather than conventional but I could do with numbers for both types.
If there isn't a definitive answer, does anyone have a rule of thumb?

Thanks

[wavetar]

I've been told up here in the Great White North by Industry Canada (our FCC) that for trunked systems, they consider 75 users per voice repeater to be a guideline. So, if you have 300 radios, they'll allow you to license up to 5 repeater pairs (1 control, 4 voice). In reality, how you set up your fleet mapping & total number of actual user groups is far more important...you can have 1000 users, but if they're all on the same talkgroup, you'll only need a single repeater since only one guy can talk at any one time. Set up 300 users on 40 different talkgroups, then you'll run into problems with a busy system.

For conventional, those things don't really apply, however they require you to have at least 25 field radios before they'll grant you a repeater license. Again, it's a guideline & exceptions can occur.

Todd

[judoka]

Thanks, that is exactly what I was looking for.
I am really trying to find out how annoyed the conventional users get when there are too many on the channel. On a trunked system with 300 users in a single talk-group, I only need one traffic channel. The system can tell me how many times a user is busied out immediately because there somebody is already on the talk-group (call collisions).
On a conventional system it just happens, people figure it out and nobody measures how long people wait until they get a chance to talk.
Dispatch controlled channels have better capacity because somebody is organising things. I have been trying to play with some Erland calculators but they don't like it when you set 1 circuit and try to find out how much load will cause a given waiting time.
With trunking and many talk-groups the erlang models start to work if you can figure out how to guess the busy hour traffic.