mtr2000

[lenny kravitz]

Hi all,
Does somebody try to connect a panel Zetron38 with a repeter MTR2000.
because i spent two days without success.

[HumHead]

Are you using the Zetron MTR2000 interface board?

There are a number of problems that make it very difficult to interface without one. I just finished setting up one with the interface board, and it worked like a champ.

Can you be more specific about what you are having problems with?

[RKG]

If Humhead's suggestion doesn't work, let us know. I can tell you how we do it with Quantars.

[batdude]

they make a cable SPECIFICALLY designed for the MTR series repeaters.

doug

[lenny kravitz]

Thanks for your advices,
but i try connect directly to the system connector J5 in the backplane.
i need something else?

[HumHead]

There are a couple of problems with trying to go straight to J5 on the MTR2000.

The first, and biggest, is that the MTR2000 only has one active Aux Audio In path at a time, while the Zetron Model 38 puts out audio and PL / DPL on seperate lines.

On many radios / repeaters there are seperate microphone audio and flat audio inputs, that can be used simultaneously but, to the best of my knowledge, such is not the case on the MTR2000. I believe that this same limitation will also prevent you from just hanging the controller off of the MRTI port.

Additionally, I believe that there is some sort of issue with the COR signal as well.

The Zetron interface is a cable with a model 38 header on one end, and a 96 pin connector, to mate with the J5 system connector, mounted to a small circuit board with various "guts", on the other. The unit comes with outstanding, and detailed, installation and configuration instructions. An important note: the board will only work on newer MTR2000s with the J5 system coonector "right side up" (Pin A1 on the bottom left, looking at the rear of the repeater). It will not work on the older units with row A at the top.

Their tech support folks are very helpful (although I thought heads were going to explode when I told them that I had replaced their stock cable) (I had to customize the interface to work with a second link radio as well)

Zetron considers the interface a proprietary joint design with Motorola, and will not share schematics, etc. From looking at the board, there looks to be a good number of level matching components, and an op-amp based active combiner for the audio lines. There were also pads and jumpers for some optional components in the audio paths, but none were installed or labeled on my board. I think there may have also been a transistor or two for the COR line, but I'm afraid that I don't recall off of the top of my head.

So, the short version: Interfacing with the Zetron interface board / cable is very easy. Interfacing without it is really ugly.

I'm afraid that I would have to suggest just getting the board.

Good luck!

[lenny kravitz]

Thanks to all of you for the help,
if someone have the model and the price more o less of the interface i´ll appreciate.
Lenny

[HumHead]

I believe that it is simply called the MTR2000 interface.

List is around $225.00, with the street price probably a bit lower (I don't recall exactly what we paid for ours)

Hope that helps!

[batdude]

The part number for the cable assembly to interface a Model 38A to an
MTR-2000 is Part #950-9919, US$225.00. Let us know if you have further
questions.



that was from zetron directly.




doug

[Bootman]

Just wondering if anyone has taken the zetron Mtr2000 cable apart to see what makes it tick (Schematic?)

[Will]

What the.. $225 for a cable!

I have always used a DB25 connector and a few wires, and a resistor, and even with the time spent to make sure it worked, it didn't cost $225.

Even the MSF5000 adaptor I designed with Zetron didn't cost $225!

eVEN i WONDER WHAT IS GOING ON IN THE "zETRON CABLE".

[wavetar]

What the.. $225 for a cable!

I have always used a DB25 connector and a few wires, and a resistor, and even with the time spent to make sure it worked, it didn't cost $225.

Even the MSF5000 adaptor I designed with Zetron didn't cost $225!

eVEN i WONDER WHAT IS GOING ON IN THE "zETRON CABLE".

You haven't seen one, obviously. There's a complete PCB on the 96-pin end with a LOT of components. I don't know exactly what it does, since I too have interfaced plenty of things to the MTR2000 directly with no problems.

Todd

[HumHead]

If memory serves, the most obvious function of the interface on the Zetron cable is to provide a mixer for the PL/DPL tones and the TX audio when using an MTR2000 as a "community" repeater.

I also seem to recall that the interface does something creative to the COR line, as well as some level matching.