RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog
 

Go Back   The RadioReference.com Forums > Commercial, Professional Radio and Personal Radio > Industry Discussion


Industry Discussion - General discussion forum for commercial and professional radio technologies. This includes manufacturers not listed below.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 04-14-2018, 12:59 PM
Member
   
Join Date: Mar 2018
Location: Dhaka, Bangladesh
Posts: 41
Default Is it okay to use vox to key up another mobile radio in a portable repeater setup?

I need to "build" a portable repeater system for some field work. Extremely low duty cycle, so I guess a two Chinese mobiles would do the job but there's no squelch detect or anything similar, can't find a way to interface with a controller. Not gonna need CW ID or anything on it. Just plain voice. Thought of using the Rx led to key up the transmitter, is that a good idea? Or the vox?

Sent from my Redmi 4X using Tapatalk
Reply With Quote
Sponsored links
  #2 (permalink)  
Old 04-15-2018, 4:03 AM
Member
   
Join Date: Apr 2016
Posts: 200
Default Depends on the radio

Quote:
Originally Posted by S21IL View Post
I need to "build" a portable repeater system for some field work. Extremely low duty cycle, so I guess a two Chinese mobiles would do the job but there's no squelch detect or anything similar, can't find a way to interface with a controller. Not gonna need CW ID or anything on it. Just plain voice. Thought of using the Rx led to key up the transmitter, is that a good idea? Or the vox?

Sent from my Redmi 4X using Tapatalk
I did this with a couple of Moto handhelds that would chirp when the scan stopped. I think it may of been GP300's. I taped the mike from one to the speaker of another. Set one to scan, and to make a tone when the scan stopped. That was enough to "open" the vox on the other. The audio was a tad muffled, but perfect copy. It actually worked pretty good as a repeater. Played with it for a few days maybe, then took it apart.
Reply With Quote
  #3 (permalink)  
Old 04-15-2018, 1:05 PM
jhooten's Avatar
Member
   
Join Date: Mar 2004
Location: Paige, Republic of Texas
Posts: 1,428
Default

If you intend to use the mic in front of the speaker trick, Put it in a sound proof enclosure lest someone walking by stubs their toe, causing them to let loose a sting of profanity which triggers the VOX.

Or, go search eBay where you can find something like this: https://www.ebay.com/itm/Walkie-Talk...sAAOSwYkBZ2E38

That device, two UV-5R radios, a push up pole(preferably non metallic), and some duct tape would put a workable repeater on the air for less than a c-note.
__________________
Jerry

I read it on the internet, so it must be true.

Last edited by jhooten; 04-15-2018 at 1:11 PM..
Reply With Quote
  #4 (permalink)  
Old 04-15-2018, 1:08 PM
Member
   
Join Date: Mar 2018
Location: Dhaka, Bangladesh
Posts: 41
Default

Actually the mobiles I saw use rj45 connectors, I could directly just make a crossover wire to hook them up. Would that be keying the transmitter properly?

Sent from my Redmi 4X using Tapatalk
Reply With Quote
  #5 (permalink)  
Old 04-15-2018, 1:20 PM
jhooten's Avatar
Member
   
Join Date: Mar 2004
Location: Paige, Republic of Texas
Posts: 1,428
Default

It would take more than just a wire cross over. Many of those radios use a condenser mic which requires a dc voltage on the mic line. Putting dc into the speaker connector would not be a good idea. You would also need to have a way to reduce the speaker output to mic level and match the impedance.

Search around on eBay. Someone may have a similar device fit the mobile CCR.
__________________
Jerry

I read it on the internet, so it must be true.
Reply With Quote
Sponsored links
  #6 (permalink)  
Old 04-15-2018, 6:04 PM
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: May 2014
Posts: 125
Default

Quote:
Originally Posted by S21IL View Post
Actually the mobiles I saw use rj45 connectors, I could directly just make a crossover wire to hook them up. Would that be keying the transmitter properly?
This was done with old Motorola Maxtrac radios. Not a simple direct wire, as stated...there are resistors and capacitors required. You have to check the pinout to see if your radios are even capable in the first place.

You asked awhile back about making a repeater...not sure what you are trying to accomplish, but another idea for your consideration--cross band repeater. There are several radios that have crossband capability. One radio, one power supply, one feedline, one antenna (dual band), and no duplexer. You can set it up for 2m input and 70cm output or both ways if you need.

Wouxun and TYT come to mind.
Reply With Quote
  #7 (permalink)  
Old 04-15-2018, 8:49 PM
Member
   
Join Date: Mar 2018
Location: Dhaka, Bangladesh
Posts: 41
Default

Quote:
Originally Posted by I_am_Alpha1 View Post
This was done with old Motorola Maxtrac radios. Not a simple direct wire, as stated...there are resistors and capacitors required. You have to check the pinout to see if your radios are even capable in the first place.

You asked awhile back about making a repeater...not sure what you are trying to accomplish, but another idea for your consideration--cross band repeater. There are several radios that have crossband capability. One radio, one power supply, one feedline, one antenna (dual band), and no duplexer. You can set it up for 2m input and 70cm output or both ways if you need.

Wouxun and TYT come to mind.
That was for a commercial project. That's coming in pretty good. Gonna use motorola mobiles for that.

This is more for a personal mobile use. And seems like I'd be better off getting a crossband repeat capable mobile is better than trying to salvage old unused radios

Thanks everyone.

Sent from my Redmi 4X using Tapatalk
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 4:06 PM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
All information here is Copyright 2012 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2015 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions