Batboard

How to connect external "PL" to a MTR 2000 repeater? Help needed badly.

I thought these radios could do PL and DPL encode and decode already. Which do you need, and why won't the internal functionality work?

Bob M.

I think what he wants is a community repeater function. For that, you need to hook in an external controller. This is a piece of cake with the Quantar, but I'm told (I've never done it) that it is more difficult with the MTR2000 unless you purchase a specially made cable, which is available from Zetron.

Actuall what I a working on is the connection of a GPS master oscillator system in order to have simulcast. The problem I am having is that when the two repeaters are on the air, there is beating between them. I was told by "simulcast solutions" to tx without pl. that works ok. The pl is then generared from the GPS oscillator which should be then inserted in the Tx..I tried hooking to the (enable)MRTI data port also the aux tx port on the i/o board. but to no avail..

MITYTONE wrote:Actuall what I a working on is the connection of a GPS master oscillator system in order to have simulcast. The problem I am having is that when the two repeaters are on the air, there is beating between them. I was told by "simulcast solutions" to tx without pl. that works ok. The pl is then generared from the GPS oscillator which should be then inserted in the Tx..I tried hooking to the (enable)MRTI data port also the aux tx port on the i/o board. but to no avail.. 8)

Take a look at this thread: http://batboard.batlabs.com/viewtopic.php?t=47205

The connector you want is J5603, the 5/10 Mhz reference input. Minimum signal 1 volts p-p, max is 3 volts p-p, high impedance

You will need the RSS to select the clock rate and a service monitor to fine tune it. You can't do it "by ear".

Martin

I'm not to sure how "simulcast solutions" planned to inject a PL tone. You have to mix it with the audio at a common point. That way you can get it to all the your sites at the right time and in the right phase. If they dont provide a point you might try an external bridge card.
When aligning the MTR2000 you need to use your external reference. After that save it and then program the radio. MTR2000 will not be ready for simulcast spec's if you dont program the codeplug into it after aligning it.
Have fun.

To mix PL and audio you need the CDN6351 (Motorola's part number for Zetron's mixer) kit.

See the topic:
http://www.batlabs.com/mtr2000.html

The voice audio and PL have to arrive at the "overlap" (also called a beat or hetrodyne) zone at the same time. To do this they have to be syncronized to about 15 microseconds or better.

You also need to decide if you will run the two sites locked, or offset one site using the the Spectracom, by 3Hz or so the null locations in the overlap "roll" as opposed to staying stationary.

You may also need alignment equipment such as the Convex TIMS. You can't align using 1000Hz tone since there is a solution every 1000us and you can't tell which of the many solutions are the only and unique correct solution for frequencies other than 1000Hz and voice.

In this kind of application most folks use delay lines like the "Convex" equipment shown on Simulcast Solutions web site. Slightly off topic, but, they also "vote" the receivers using something like the JPS products shown on the same web site.

Good luck. Bob Johnson

OK guys, thank you for your replies. After much engineering between myself and the people at simulcast solution. We found the easy fix without any form of tuning,alignment or any condsideration for timing..Due to the fact that I am not always on the BB.If anyone need this info,please free to pm me or email [email protected]