1225 Radius Repeater Question

PriorityOne · Post by **PriorityOne** » Fri Jan 28, 2005 8:16 pm

I have a radius 1225 repeater, and Im wondering if it is possible to have the unit repeat my frequency without a PL. The idea is to have 2 sets of users with different PL's able to access this repeater without hearing eachother. Obviously I know that only one party can TX at a time. Anyone know if this is possible?

Al · Post by Al » Fri Jan 28, 2005 8:42 pm

With the GR1225, if you set the RX side up for CSQ, that removes the second qualifier of [the correct] PL on the receive side of the repeater, allowing transmitter keying on only a carrier on the input channel. Unfortunately, then anyone using any(or no) PL can also key up your repeater. The best solution is to use an external(to the R1225) community repeater tone panel to allow *just* the two PLs that you are using to key up the transmitter.

PriorityOne · Post by **PriorityOne** » Sat Jan 29, 2005 6:23 am

So, if any carrier or PL can come in if I remove the RX side, would it remain the same in the way out? Ex: users with a DPL of 364 would get repeated with a 364 and users with a DPL 754 would stay 754?

Post by **wavetar** » Sat Jan 29, 2005 5:54 pm

There are two audio repeat modes in the GR1225, called 'flat' and 'EIA'.

In the default EIA mode, the repeater will strip any incoming PL/DPL, and Encode whatever PL/DPL you've programmed into the unit. If you set it for CSQ on the TX & RX, you will not get any PL/DPL out on the transmit side, regardless of what PL/DPL might be incoming.

In flat mode, it'll transparently repeat whatever comes in, although the level will be somewhat lower. An incoming PL deviation of 750Hz will come out at approx 400-500Hz.

Either way, there isn't a 'native' way for the repeater to activate on multiple specific PL/DPL codes, and ignore others. An external controller would be needed for that, as was mentioned.

Todd

PriorityOne · Post by **PriorityOne** » Sun Jan 30, 2005 7:58 am

wavetar wrote: In flat mode, it'll transparently repeat whatever comes in, although the level will be somewhat lower. An incoming PL deviation of 750Hz will come out at approx 400-500Hz.

OK thanks, I guess flat mode is what I want to try. I just want the repeater to repeat any PL and keep it the same on the way out. I dont really care about locking out others as of yet.

RKG · Post by **RKG** » Sun Jan 30, 2005 4:34 pm

Passing received PL through a repeater is likely to be unreliable.

If you want to have two groups who have access to the machine but neither hears the other, what you are looking for is what is known as "community repeater" capability. So far as I am aware, with the GR you would need an external community repeater panel. I do know that both the Quantar and the MTR2000 have a limited community repeater function built into their control modules.

Post by **wavetar** » Sun Jan 30, 2005 5:20 pm

RKG wrote:Passing received PL through a repeater is likely to be unreliable.

In theory yes, but I really haven't found it to make any discernable difference with Motorola repeaters & radios in the field. They decode PL/DPL reliably well below 200Hz deviation, for the most part. Useable range remains the same in both flat & EIA modes. Can't speak for other manufacturers though, haven't played with them.

Todd

Al · Post by Al » Sun Jan 30, 2005 6:24 pm

I agree with Wavetar....I maintain three GR1225s all set up for flat mode to pass audio and PL. They're used under weak RX signal conditions at times, and I've never had a problem with the correct PL being detected at the receiving portable. Your mileage could vary from these experiences if you're using DPL.