Motorola Quantar Repeater Controller!

[wa8pyr]

I need to buy another Northcomm Technologies controller for the new (to me) 900MHz Quantar I picked up yesterday for $300.

First, I think I'm going to stalk you; you're getting more and better deals on Quantars, and here I thought I was doing pretty well getting my hands on surplus Motorola gear the last couple of years.

Second.... I'm getting devilish ideas.

I still haven't quite figured out how I did it, but my MSF5000 repeater passes the repeat audio through the SSCB, yet gets courtesy tones, DTMF decode and enable/disable from the RC85 controller, resulting in that wonderfully clean Motorola audio, and lots of cute noises for courtesy beeps (my latest has been the NASA Quindar tones to indicate a signal coming in on the remote base).

Reading up on that Northcomm unit I have a sneaky suspicion that I might be able to use wildcard programming in the Quantar to let my RC85 controller generate courtesy tones, handle DTMF decode as well as repeater enable/disable, and generate Quick-Call II tones for paging, yet keep repeat audio inside the Quantar where it belongs. The cute noises the RC85 makes have always been popular with the users, but so has the nice clean Motorola audio.

 

[prcguy]

It is fun experimenting with this stuff. I also passed on a couple more range 2 UHF Quantars in the mid $600 range and they had P25. They are out there for good prices if you look around.

First, I think I'm going to stalk you; you're getting more and better deals on Quantars, and here I thought I was doing pretty well getting my hands on surplus Motorola gear the last couple of years.

Second.... I'm getting devilish ideas.

I still haven't quite figured out how I did it, but my MSF5000 repeater passes the repeat audio through the SSCB, yet gets courtesy tones, DTMF decode and enable/disable from the RC85 controller, resulting in that wonderfully clean Motorola audio, and lots of cute noises for courtesy beeps (my latest has been the NASA Quindar tones to indicate a signal coming in on the remote base).

Reading up on that Northcomm unit I have a sneaky suspicion that I might be able to use wildcard programming in the Quantar to let my RC85 controller generate courtesy tones, handle DTMF decode as well as repeater enable/disable, and generate Quick-Call II tones for paging, yet keep repeat audio inside the Quantar where it belongs. The cute noises the RC85 makes have always been popular with the users, but so has the nice clean Motorola audio.

 

[kb9tyc]

That company also makes one the the best plug in Quantar cable set ups if you use a SCOM controller.

I agree. We have 2 Quantars set up with the cable and SCOM 7330.

 

[wa8pyr]

It is fun experimenting with this stuff. I also passed on a couple more range 2 UHF Quantars in the mid $600 range and they had P25. They are out there for good prices if you look around.

OK, here's another one. . . what's the connector? I've always known it as a 50-pin (or 25-pair if you prefer) Telco connector, but I've been tearing my hair out going through Mouser and Digikey trying to find just the connector that plugs into J17 on the Quantar. I'm swimming in multi-conductor wire and can build my own cable; I only need half a dozen connection points anyway (COR, PTT, RX Audio, TX Audio, Ground, and one I/O pin to go to TX INHIBIT).

 

[jeepsandradios]

Are you looking for the RJ21 ?

 

[vagrant]

It is a 50 pin male Telco connector that plugs into J17 on the Quantar. The Northcomm controller already has that mounted on the backside, so no cable/wiring is needed.

Here is the Northcomm card. I plugged mine right into the back of the Quantar. I may not understand your needs.

 

[wa8pyr]

Are you looking for the RJ21 ?

That's the one. Great, yet another designator for that connector; so far I've seen it referred to three different ways! I'll do a search for RJ21, thanks!

Here is the Northcomm card. I plugged mine right into the back of the Quantar. I may not understand your needs.

I've got beaucoup repeater controllers lying about the shop (well, three or four anyway including an RC85), all of which have courtesy beep and do DTMF decode for enable/disable, etc. So, I'm thinking of using an existing controller to do what the Northcomm controller is doing; I can most likely make one of mine do what I need, while gaining a bit of space in the shop and saving $109 at the same time.

I suspect the only real functional difference is that the Northcomm doesn't have an audio path from the receiver to the transmitter, just an input from the RX for DTMF decode, and an output to the TX for courtesy beeps; all the controllers I have include variable repeat audio level so what I think I can do is turn that to zero on the controller and simply use it for courtesy beeps, DTMF decode and so on, everything but passing the repeat audio.

If it doesn't work I'll get a Northcomm controller, but it won't cost anything but a little time (and a few bucks for the RJ21 connector) to at least give this a try first. Like @prcguy said, it's fun to experiment with this stuff.

 

[jeepsandradios]

They do make one that is a breakout that may be helpful in what you are doing. I normally just use a 2' jumper to a punch block. (Think MSI used to ship a 12')

 

[wa8pyr]

They do make one that is a breakout that may be helpful in what you are doing. I normally just use a 2' jumper to a punch block. (Think MSI used to ship a 12')

Trying to avoid using a punch block if possible. I've got two or three lying around here along with at least a couple 25-pair patch cables, but really don't want to go down that road for only 4 to 8 connections. I'd rather whip up a patch cable with the RJ21 on one end, a DB25 on the other end, and a hunk of CAT5 in the middle. That way I've got the four connections I really need (COR, PTT, RX audio, TX audio) plus four others to work with if needed, without a massive 25-pair cable and punch block cluttering things up.

Northcomm sells one (RJ21 to DB25, intended for SCOM controller) for $109, but I'm a cheapskate ham at heart; if I can spend an evening building one myself for free or next to it, I'm a happy camper. Suppose I could take an RJ21 off one of the cables I have lying around here, but cleaning out the connector. . . there are limits.

 

[prcguy]

A Quantar I bought came with a 50 pin to RJ45 adapter that was already wired for COR, PTT, RX and TX audio. I think its a standard Motorola part.
Look up a Motorola 58-82653X11.

Trying to avoid using a punch block if possible. I've got two or three lying around here along with at least a couple 25-pair patch cables, but really don't want to go down that road for only 4 to 8 connections. I'd rather whip up a patch cable with the RJ21 on one end, a DB25 on the other end, and a hunk of CAT5 in the middle. That way I've got the four connections I really need (COR, PTT, RX audio, TX audio) plus four others to work with if needed, without a massive 25-pair cable and punch block cluttering things up.

Northcomm sells one (RJ21 to DB25, intended for SCOM controller) for $109, but I'm a cheapskate ham at heart; if I can spend an evening building one myself for free or next to it, I'm a happy camper. Suppose I could take an RJ21 off one of the cables I have lying around here, but cleaning out the connector. . . there are limits.

 

[wa8pyr]

A Quantar I bought came with a 50 pin to RJ45 adapter that was already wired for COR, PTT, RX and TX audio. I think its a standard Motorola part. Look up a Motorola 58-82653X11.

Oooooooooooo... ePray here I come!

Update: Got one. $13 and change including shipping. Might just have to grab another just on general principles.

 

[vagrant]

Two for $16 shipped on eBay so you can enjoy three.

 

[wa8pyr]

Two for $16 shipped on eBay so you can enjoy three.

Ordered. Order was suddenly cancelled on the one I bought yesterday, saying "out of stock."

 

[vagrant]

Nice! Your result will look better than the cables I made using breakout connectors for URIx to Yaesu and Icom repeaters using Raspberry Pi’s as a controller with Hamvoip few years ago. I still have some tinkering to do with the Northcomm, but I’ll be right behind you when I next fool around with the Quantar, a URIx and a Pi for control, but mostly for linking.

 

[wa8pyr]

Nice! Your result will look better than the cables I made using breakout connectors for URIx to Yaesu and Icom repeaters using Raspberry Pi’s as a controller with Hamvoip few years ago. I still have some tinkering to do with the Northcomm, but I’ll be right behind you when I next fool around with the Quantar, a URIx and a Pi for control, but mostly for linking.

Well, it might not work so well as I had hoped, at least not without some tinkering. Officially that adapter is a "MSF 5000/Quantro/Simulcast Remote Site" connector. Don't think I've ever seen a Telco connector on a MSF5000.

Our local Motorola rep sent me the wiring diagram for the adapter. It's got Line 2 and PTT connections, with another pin set up for RX Code Detect (which I can use directly for CTCSS detect). However, it has nothing for Line 1; instead it has connections for pins 34 and 9 (Gen TX Data + and -), which is "modulation signal from simulcast equipment." I'll have to do a bit more digging to see if that can be used for what I need, but so far it's not promising. May have to get some of the audio off the orange wireline connector. Bummer.

If the MRTI connector used a normal DB25 I could go there but while it's shaped and sized like a DB25, the pin arrangement is very odd, so that's out unless I want to kludge something up. Trying to avoid kludges if I can; looks sloppy.

If I can find RJ21 solder-type connectors it may end up being easier to just build up a couple of cables myself rather than try to adapt that Motorola adapter.

Update: Looks like Gen TX Data might work after all. According to the Wireline Interface Board section of the service manual (thank God for complete documentation), "Summing and gating circuitry is provided on the WIB to allow PL tones, reverse burst, and TX audio (GEN TX DATA) to be combined and output to the VCO in the exciter module (after processing in the SCM) to directly modulate the RF carrier. The simulcast circuitry is controlled by the Station Control Board microprocessor via the WIB microprocessor and upper PASIC on the WIB." And here I may have been worried for nothing; we'll see how it goes.

 

[vagrant]

I have cut a perfectly good cable so I could have a clean connector on one end, and then try to make the other end as pretty as I can. Half ugly is better than all ugly. A box can also hide lots of ugly when re-splicing a cable, or two different cables. I am not doing this professionally, so I have lots of leeway. Function over fashion is usually the demand from my fellow amateurs. They rarely see the man behind the green curtain and if they complain, I will task them to start working on a resolution themselves...or perhaps enjoy it the way it is.

I would like to make it look pretty, but time and money are not aways abundant. With a rack system, sometimes you can get away with business in the front and party in the back.

 

[wa8pyr]

I have cut a perfectly good cable so I could have a clean connector on one end, and then try to make the other end as pretty as I can. Half ugly is better than all ugly. A box can also hide lots of ugly when re-splicing a cable, or two different cables. I am not doing this professionally, so I have lots of leeway. Function over fashion is usually the demand from my fellow amateurs. They rarely see the man behind the green curtain and if they complain, I will task them to start working on a resolution themselves...or perhaps enjoy it the way it is.

I would like to make it look pretty, but time and money are not aways abundant. With a rack system, sometimes you can get away with business in the front and party in the back.

I've done the same (and in fact have one for testing on this repeater), although 25-pair telco cable is a pain to work with, even a piece only a foot long. I'd rather have just a clean RJ21 connector, solder in a piece of CAT5 of the appropriate length to the needed pins, put the desired connector (in this case an RJ45) on the other end, and done. Nice neat cable that's easy to work with.

 

[wa8pyr]

Ordered. Order was suddenly cancelled on the one I bought yesterday, saying "out of stock."

Well, so much for that. After nearly a month and no package I queried the seller; turns out they had issues with packages going to USPS either not getting scanned, lost, etc and refunded my money. Given the news stories about USPS suffering the usual Christmas rush and having additional load placed on them when UPS and FedEx prioritized vaccine shipments (rightly so), and being COVID-shorthanded to boot, I figured that was the likely cause. According to the news packages were getting dropped off at post office docks and then sitting for days, unscanned, because they were so shorthanded; until it gets scanned the USPS doesn't even know it exists.

No biggie. Probably best if I make my own connectors for J17 anyway; that way I can decide what connections I want to use and configure wildcards appropriately.

 

[vagrant]

A package was shipped to me using USPS Priority Mail from Colorado to California on 12/26. Three day delivery turned into nine as I received it on 1/4.