Jump to content
  • 0

Motorola XPR-4550 radios for GMRS repeater, will they work?


Question

Posted

I have 14) XPR 4550 and 3) XPR 5550 radios that where pulled from a bus service. All are programmed for that service. Can these be programmed for GMRS repeater use? What cable would or could be used to link a pair of properly programmed radios?

 

WQWY888

KA6GOU

IMG_6503.JPG

IMG_5551.jpg

IMG_5550.jpg

14 answers to this question

Recommended Posts

  • 0
Posted

I haven't played with the XPRs but I have played with several of their predecessors, the XTLs.. So, my (semi) educated guess is that IF they are the UHF versions and IF you can get the software for them, then yes, they will work.
But I will yield to whatever anyone that has more experience with the XPRs than I do has to say.

I dont understand your question about linking the radios with a cable, because, why would you want to do that? Unless what you are asking is "can these radios be used AS a repeater".. If so, please deconfuckulate us.

  • 0
Posted

Yes, my plan is to make a few repeaters. So these would be used in pairs. I’ve made a few using the cdm radios using an Id-o-matic and some generic link cables from eBay on those but I’m not finding any available for the XPR radios. 
 

 

  • 0
Posted

See attached model number chart.  These are 450-512 MHz models.  These will work on GMRS but not amateur.   I have many XPR4550 radios and a few 5550. They have superior receivers from a susceptiility/overload perspective.  They are perfect radios for creating a repeater.  Their accessory outputs are easy to program.   They have a design flaw where their accessory port output of low frequency CTCSS codes (below 114.8 Hz) or DCS are poor.   But that is fine.  Not sure about cables.         

XPR 4550 Model Number Chart.pdf

  • 0
Posted

They will work the same as a CDM, or any other MSI Radius line mobile. The difference is the accessory cable pino ut. You'll need to buy the kit of plug and pins and make your own cable. Also need to program the pins in the radio. Dont run them on high power or they wont last long. Basicaly the XPR 8400 repeater has two of those in the box. 

 

  • 0
Posted
6 hours ago, gortex2 said:

.... Dont run them on high power or they wont last long. Basicaly the XPR 8400 repeater has two of those in the box. 

 

Good recommendation when using those model for repeater operation.  But if/when the transmitting radio fails, just swap the radios around.  

  • 0
Posted
15 hours ago, tweiss3 said:

Those are ConnectPlus. You may have issues removing trunking firmware and going to a standard firmware. I have not personally made that change, so I cannot walk you through it.

Does the FW need to be removed, or can he just program a conventional channel in them and go with that?  Or does CP preclude programming a conventional channel?   

  • 0
Posted
7 hours ago, intermod said:

Does the FW need to be removed, or can he just program a conventional channel in them and go with that?  Or does CP preclude programming a conventional channel?   

From what I can tell, it can be programmed around, I hope!!

  • 0
Posted

We have a county near me that has an interface cable for XPR4550s for their vehicular repeaters in the ambulances.

I've put in a few and its just a straight thru cable from radio to radio.

I don't think its a Motorola part, but you would probably want something more like the IDoMatic like the other user said.

But they are great radios.

  • 0
Posted

Looks like I'm late to the party on this particular thread, but for anyone who may need info about this topic, This absolutely can be done.

For a repeater, you can program one radio with an analog conventional RX channel (upper frequency for the GMRS pair) and the other radio for the lower TX channel.

In the CPS (Customer Programming Software) under General > Accessories, scroll down to the 'GPIO Physical Pins' section (this correlates to the accessory connector on the back of the radio). You need to assign a pin to be 'Ext Mic PTT' (on transmit radio), and another to be 'PL/Talkgroup Detect' (receive radio) - which is the same as COR label on other radios. I usually do GPIO 1 as PTT and GPIO 2 as Detect. This will make PTT physical pin #17 & Detect physical pin #19 on the back of the radio. Active level low and no debounce.

You will need Motorola accessory connector (part #: PMLN5072A) for each radio. Crimp pins on wires (22 awg is fine) and insert into the following pin locations on the connectors; RX Pins [14, 16, 19], TX Pins [11, 16, 17]. If you are connecting each radio to a controller, you may want to use all 5 pins below on each radio depending on what functions you would like to controller to be able to do.
TX Radio Side:
11 - Mic/Audio In  [this connects to receive radio's pin 14]
14 - RX Audio Out [not used on TX side for 1-way repeater]
16 - Ground [connects to receive radio's pin 16]
17 - PTT (Program GPIO 1) [connects to receive radio's pin 19]
19 - PL/Talkgroup Detect (Program GPIO 2) [not used on TX side for 1-way repeater]

To connect the radios and use them like a repeater, you will need to order some accessory connectors (Motorola part# PMLN5072A) to build a cross-over cable to allow the receiving radio to key up the transmitting radio. You can accomplish this with a single cable connected between the radios, unless you have a separate repeater controller you would like to use to add additional features like DTMF, time announcements, CWID, etc. Note that if you are using this 'repeater' on GMRS channels, if you are not regularly identifying your callsign yourself, you will need a controller to do it for you. Most controllers will identify your callsign with morse code, some will also air voice. Even if someone else is talking on your repeater and you are not part of that conversation and not transmitting, your repeater is still being used under your license, and therefore is required periodically identify with your license. There are many simple controllers available on the market that are made just for airing identification (the IDoMatic has been mentioned a few times already), so I would recommend to at the least get one of those ID controllers and work it into your cable interface if you just plan on connecting two mobiles together with no other advanced controller - so you stay legal.
Depending on if you use a controller and what controller you use, the custom cables you will have to build will differ.

Another programming feature you will need is Wideband, since you will be using it for GMRS. The radios come with the ability to program as wideband, but because of the narrowband mandate, you don't automatically get that feature. You will actually need to go through the "training" from Motorola (to cover their butts in case you use wideband on frequencies you're not supposed to), then you actually have to purchase the wideband feature for your programming software only. Once purchased and activated in the software, your software will be able to program wideband on any Mototrbo radio. Again, you only need the wideband feature license for the software on the computer you intend to use and NOT for each radio. If you don't have a Motorola account and access to MyView, etc. this will be harder to accomplish and you'll want to talk to an authorized Motorola partner who can help you purchase and activate the feature.

These are great radios and I use the XPR series often on both GMRS and analog/digital business frequencies; 4550, 5350, 5550, 7550.
I own my own licensed digital & analog business systems and GMRS systems. I also have a Motorola account to access CPS, firmware, etc.

One of the issues you might run into with used radios is that the codeplugs could be password protected and you may not know that password, so you can not read/program the radio.
In this case, you will need to use the same or slightly later firmware version package to 'Recover' the radio in the CPS. This will delete the whole current codeplug in the radio, and load the firmware back to the radio with a blank, factory codeplug, so you will not be able to copy any of the current data/channels, etc. that were on the radio before you started, but it will re-flash the radio with a blank codeplug allowing you to program it and start over. The latest firmware for the 4550 is version 1.12.17.

If you need to rackmount your mobile repeater, there is a great company out of Canada called Alberta Radio Supply who makes 19" mounting plates in a variety of different configurations. You could get one that will allow you to mount two 4550's side-by-side. They also have some that will mount power supplies, scanners and other makes/models of two-way radios. They also sell on ebay (where I got mine).

spacer.png

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Answer this question...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.