Understanding Capacity Plus trunking

[garys]

I'm using DSD+ to track and map out a large Cap+ VHF system which I think is used by the Boston Public Schools for buses. I've noticed a couple of new (to me) features.

First, the system seems to be broken into two parts. LCN 1 is separate from the other five frequencies in the system. It has it's own rest channel and most of the traffic is ARS location data with occasional private calls voice traffic.

LCN 2-6 operate as a typical Cap+ system with the Rest Channel moving as normal. There is mostly Private Call traffic on this, with very rare RAS. I've seen ARS traffic just once on this part of the system.

One other thing I've noticed, which I've never seen before is "Radio Check" traffic. This is none voice and seems to be a "ping" of the individual radios with a ACK signal sent back.

I don't know if any of these are new or unique features, but I've never seen them on the other Cap+ systems I've followed.

Since the normal school year doesn't start for a few weeks, traffic right now is limited. It will be interesting to see how busy this gets.

 

[mtindor]

I'm using DSD+ to track and map out a large Cap+ VHF system which I think is used by the Boston Public Schools for buses. I've noticed a couple of new (to me) features.

First, the system seems to be broken into two parts. LCN 1 is separate from the other five frequencies in the system. It has it's own rest channel and most of the traffic is ARS location data with occasional private calls voice traffic.

LCN 2-6 operate as a typical Cap+ system with the Rest Channel moving as normal. There is mostly Private Call traffic on this, with very rare RAS. I've seen ARS traffic just once on this part of the system.

One other thing I've noticed, which I've never seen before is "Radio Check" traffic. This is none voice and seems to be a "ping" of the individual radios with a ACK signal sent back.

I don't know if any of these are new or unique features, but I've never seen them on the other Cap+ systems I've followed.

Since the normal school year doesn't start for a few weeks, traffic right now is limited. It will be interesting to see how busy this gets.

Gary,

Do a google search for: motorola data revert

Data revert repeaters are those that have been designated for data-only on a Motorola trunked DMR system like Capacity Plus. What you are describing seems to be a data revert repeater.

In Toledo Ohio, the TARTA system appears to have such an active frequency as well -- it advertises itself as part of a CAP+ site, but it is used for data traffic and has never been seen to carry voice traffic.

Mike

 

[garys]

Thank you! That seems to be what I'm seeing, but there is some limited Private Call traffic on this side as well. As I noted, it seems to be a school bus system, so traffic right now is limited to year round programs. School starts up here in about two weeks, so I'll see how busy it gets then.

Gary,

Do a google search for: motorola data revert

Data revert repeaters are those that have been designated for data-only on a Motorola trunked DMR system like Capacity Plus. What you are describing seems to be a data revert repeater.

In Toledo Ohio, the TARTA system appears to have such an active frequency as well -- it advertises itself as part of a CAP+ site, but it is used for data traffic and has never been seen to carry voice traffic.

Mike

 

[garys]

At the risk of posting this link in more than one forum, as well as many people already having a copy, here is a link to the MotoTrbo System Planner.

It's close to 400 pages long.