Crossband between MTR2000s without external controller?

This forum is for discussions regarding System Infrastructure and Related Equipment. This includes but is not limited to repeaters, base stations, consoles, voters, Voice over IP, system design and implementation, and other related topics.

Moderator: Queue Moderator

Post Reply
256QAM
Posts: 67
Joined: Fri Oct 14, 2011 3:29 pm

Crossband between MTR2000s without external controller?

Post by 256QAM »

I remember seeing a diagram in the Quantar service manual for having back to back repeaters to crossband without an external controller. Is there a similar provision to link two MTR2000s in the same rack without the addition of an external controller using just the wireline card? I have an application where it would be helpful and an external controller is overkill feature-wise for the site.
PETNRDX
Posts: 868
Joined: Sun Nov 25, 2001 4:00 pm
What radios do you own?: Too many

Re: Crossband between MTR2000s without external controller?

Post by PETNRDX »

You should be able to interconnect a pair of MTR's as an RA setup.
That is a "repeater" for say mobiles and portables.
And the RA part is the control link to a control station, like a dispatch center.
Its been years since I set a pair up that way, but I know it can be done via the J5 system connector on the back plane.
CAREFULLY read the manual (I think there is one on Repeater-Builder) and interconnect the obvious things.
Rx Aud out to TX aud in, COR to PTT going both directions, etc.
You have to program TX lockout or the thing will hang.
And you might not be able to have one of them be full duplex.
Been years...
Pretty sure you can do it, but its a lot of trial and error.
Wireline won't do it.
The stations respond to FUNCTION tone sets, but they don't generate function tones.
So a station in receive won't make the function tones for the other to TX and vice versa.
You can use the wireline connections for the audio crossconnect, but you have to use the J5 system connector for COR and PTT.
And you have to figure out the "crossbusy" lockout or they will just lock up.
Steve K.
256QAM
Posts: 67
Joined: Fri Oct 14, 2011 3:29 pm

Re: Crossband between MTR2000s without external controller?

Post by 256QAM »

I'll have to verify if I can manipulate, I think COR is Active High and PTT is Active Low so I'd have to either find a way to change in CPS or build a small circuit to invert the signals. Hmm..
Karl NVW
Posts: 174
Joined: Wed Sep 03, 2003 7:13 am

Re: Crossband between MTR2000s without external controller?

Post by Karl NVW »

With the right station programming options, COR changes polarity to become Rpt PTT which also includes a hang-timer value. And if you are building an interface, 4N35 optoisolators are ideal for polarity shifting.
Karl - WA8NVW AFA5VB
SHARES + NCS
256QAM
Posts: 67
Joined: Fri Oct 14, 2011 3:29 pm

Re: Crossband between MTR2000s without external controller?

Post by 256QAM »

Would that be out of the box with just the wireline card or do I need a wildcard as well?
Post Reply

Return to “Base Stations, Repeaters, General Infrastructure”