Ice-T
Prolific Contributor
- Joined
- May 30, 2012
- Messages
- 229
I just wanted to share a tech tip that I've found very useful, especially in terms of testing XPR/MTR TRBO repeaters. Since most of us still only have analog service monitors, trying to do a 'quick' test in the field on a digital programmed XPR/MTR can be a pain. Many of you have probably resorted to re-programming in analog mode temporarily for testing, then back to digital afterwards.
By using the channel select feature, it's possible to have a secondary analog 'test' channel in the repeater, that can be accessed by a simple jumper on the repeater accessory/MRTI connector.
In the XPR for example, program in a second analog channel with the same frequencies as the digital channel, with a desired PL (I tend to use 156.7 as a standard). Set pin #19 for "channel select 1" (even though you want it to switch to 'channel 2', use 'channel select 1'...the repeater treats the first channel as 'zero'). Place a jumper between pin 19 and any ground pin (12, 16, 18) in an accessory plug. When you plug this connector into the repeater, it will re-boot and default to the analog channel. Do your testing, and remove the jumper. The repeater will once again re-boot and now default back to the digital channel.
We now set up all our deployed repeaters this way during initial set up and testing, and leave it for future field testing.
This can also have other uses. As an example, I recently set up a customer system whereby they had multiple repeaters mounted in transportable cases for rapid temporary deployment. They would primarily use a single repeater during an incident, and had TRBOnet connected to base stations for GPS tracking, using Enhanced GPS. They wanted the option of linking multiple repeaters in an IPSC configuration using wireless canopy links, if needed for greater coverage. Problem being, with Enhanced GPS, for single site repeaters you set the timing (periodic window reservation) in each repeater. For an IPSC system, only a single repeater is set to provide timing for the entire system, the rest of the repeaters have the timing set to 'none'. If you do not do this, GPS updates will only go out over the repeater the radio is sending on, they do not go across the entire system. So, we set up a secondary digital channel that was programmed identically to the primary channel, except it had the timing set to 'none'. When the customer wants to link repeaters, they simply plug the accessory jumper into the desired repeaters, leaving a single repeater without a jumper to be the timing master for the IPSC system. Works great!
Hopefully this helps out some of you.
Ice
By using the channel select feature, it's possible to have a secondary analog 'test' channel in the repeater, that can be accessed by a simple jumper on the repeater accessory/MRTI connector.
In the XPR for example, program in a second analog channel with the same frequencies as the digital channel, with a desired PL (I tend to use 156.7 as a standard). Set pin #19 for "channel select 1" (even though you want it to switch to 'channel 2', use 'channel select 1'...the repeater treats the first channel as 'zero'). Place a jumper between pin 19 and any ground pin (12, 16, 18) in an accessory plug. When you plug this connector into the repeater, it will re-boot and default to the analog channel. Do your testing, and remove the jumper. The repeater will once again re-boot and now default back to the digital channel.
We now set up all our deployed repeaters this way during initial set up and testing, and leave it for future field testing.
This can also have other uses. As an example, I recently set up a customer system whereby they had multiple repeaters mounted in transportable cases for rapid temporary deployment. They would primarily use a single repeater during an incident, and had TRBOnet connected to base stations for GPS tracking, using Enhanced GPS. They wanted the option of linking multiple repeaters in an IPSC configuration using wireless canopy links, if needed for greater coverage. Problem being, with Enhanced GPS, for single site repeaters you set the timing (periodic window reservation) in each repeater. For an IPSC system, only a single repeater is set to provide timing for the entire system, the rest of the repeaters have the timing set to 'none'. If you do not do this, GPS updates will only go out over the repeater the radio is sending on, they do not go across the entire system. So, we set up a secondary digital channel that was programmed identically to the primary channel, except it had the timing set to 'none'. When the customer wants to link repeaters, they simply plug the accessory jumper into the desired repeaters, leaving a single repeater without a jumper to be the timing master for the IPSC system. Works great!
Hopefully this helps out some of you.
Ice
