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Now it's time to set up an NHRC-4.   The target repeater will be my 147.240.   It now has a -3, but now I want to link it to my 443.2250 which has a full controller and autopatch.  Think of this site as very under construction.  I'm actually using it as my notes for the project.  I'll explain things as I do them so I can refer back to it later.

Upside to going with a -4: I'll be able to bring the 440 up on 2m as a remote base.    The 440 is at another site.  I already have a GE Mastr II Voting RX on 443.225 at the 2m site.   I also have a 6m RX/440 TX as the link TX.    It will hopefully be just a case of bringing it all together.

Downside:  The -4 has no voice storage.  Back to boring CW.

How about doing both?  Cascade the -4 and -3 somehow.  Could work.

Which will be repeater and which will be Remote Base?   Good question.   I can see reasons to make each the master machine.

First, here is the info on the controller.

Since the 147.240 is already on the air, and that I don't want to test all this in a boiler room, I'll do the connections on another Exec II I have here at home.  If I get the functionality right, I'll move it over to the 2m site.  The nice thing is that I have standardized on the connections to the Exec II's, so it should just be a case of plug-in and adjust audio levels.

I think I'll go with the 2m being main, and the Link RX and TX as the RB.  I hope the RB can control the -4.   I have a lot more 'smarts' on the 440 repeater.    It has an RLC-2a.  I could get it to send DTMF commands to the NHRC-4.   Just checked the docs.  DTMF only on the primary port.  Bummer.  I could reverse roles.  Make the Link the primary, then make the 2m repeater a married slave.  In my case, the link RX and TX are in separate chassis.

Now I'm thinking along the lines of leaving the -3 in the 2m radio, and inserting the -4 RB connection before or after it.  The -3 would let me run the 2m repeater from 2m, and the -4 would be controlled on 440, or by the controller on 440.  This makes the installation a lot more complicated, but the flexibility might be worth it.    I have two NHRC-2's on the bench, so I can beta test everything working together.   The wiring won't be real neat.   The power should come in with the repeater input, not the RB.   I can't think of anything that the -3 gives me that the -2 can't.   That will free up the -3 for use elsewhere in the network.

The -2 commands will have to come in on the 2m input, -4 on the 440 RX.  Which side of the -2 should the -4 be on?  The -4 will be pretty quiet.  I don't expect to use any tones or ID on the 2m side of the -4.   Since I don't think I need to have the voice from 2m on 440, I think it might make sense to have -4 hear the 2m RX only, then pass that to the -2.   

If the system is linked, 2m listeners will hear IDs from the -2 in real voice and the RCL in a synth voice.   440 listeners will hear only the RLC real voice.    I'll program the -4 to not ID on the RB port.  

I have the target Mastr Exec II base on the bench.  I'm not sure when I got this one, but it was in my 'in' pile of equipment.   It's untouched, so I have to start from scratch.   For those into history, this radio used to be used in a Fire Station.   It has a DC remote board, but I remove that.  First thing I have to do is modify it for repeater operation.  I'm using my own web page as a source for information about the mods.  

Now I'm thinking of using both controllers in parallel, or let them piggy back each other.   On the 2m side, the -2 controller will be vocal, the -4 will be quiet and just replay what it gets from the 443.225 RX.    So, someone on 2m will hear a simple beep when the other station is on 2m, and the more complex courtesy beep from the hub system.   How will the radio like having two controllers?  I don't know.  I might need to add some diodes on the PTT and CAS lines.

I was thinking about alll this in traffic today.   One thing I've overlooked:   Double audio.   On the 2m TX site, I'll get the local repeated audio AND the same audio coming from the hub site.   This would cause a lot of echo and distortion.   Right now, I'm going to keep things real simple and just hook up the -4 Main Repeater port to the 2m repeater, then experiment with the different modes to see if I can get any of this to work.

Here's how I'll wire it.

Repeater 8 Pin Header Use My color
GE Mastr II  Base, J901
1 +13.8 Volts Red 5
2 CAS+ White 12
3 PTT Violet 4
4 RX Audio Orange 9
5 TX Audio Blue 1
6 Fan/Digital output Brown 11
7 Ground Black 3
8 Ground    
  Ground Shield 10




Last update: 01/14/08 01:12:18 PM

Except for portions owned by others, Copyright: Ray Vaughan, 2008