Anyone know where?
I'm trying to use a GTX mobile for an IRLP RoIP node.
GTX Mobile PL/DPL dectect output line?
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Jonathan KC8RYW
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GTX Mobile PL/DPL dectect output line?
73 DE KC8RYW
Random Motorola Part Number:
SYN1894B - V3m Sprint-branded Battery Cover
Random Motorola Part Number:
SYN1894B - V3m Sprint-branded Battery Cover
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Jonathan KC8RYW
- Posts: 1747
- Joined: Fri Dec 28, 2001 4:00 pm
Rumor has it that a fellow has worked out how to use them as repeater receivers, but he thinks he's going to make a living at it so he's not telling. Presumably he could help you, for a price, but I have yet to hear any announcement from him.
Last edited by W6JK on Sat Feb 24, 2007 5:14 pm, edited 1 time in total.
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Jonathan KC8RYW
- Posts: 1747
- Joined: Fri Dec 28, 2001 4:00 pm
Hi guys.. The GTX mobile makes for a great repeater receiver. I'm using one on my repeater. The CSQ detection point in the radio is sort of a pain to locate but it's there. I apologize, I don't have a digital camera to take a picture of where I snagged the signal from, however, I will at least make a meager attempt to explain where it is.
- Pop the top cover off the radio.
- With the front of the radio towards you, look on the left hand side. There is a fancy looking rectangular flat pack chip on the left, mine has the Intel brand stamped on it.
- There are some small round thru-hole connections just above that chip going towards the back of the circuit board to the 16 pin connector. The COR signal is available from one of those thru-hole connections. It isn't but maybe 1/4 inch up from the Intel chip. My best suggestion is to grab your voltmeter, run a signal into your radio until you find this point. Be aware that you have to use very fine wire to make connection to this thru-hole point. I modified my receive radio by disconnecting the 0 ohm resistor at the 16 pin accessory connector, pin 14 (mic hook) and ran my COR signal to that pin instead. This way, I have COR coming out the back. And by the way, I did not have to add a buffer transistor to utilize this signal. I'm using a Link-Comm RLC-1 controller. The RLC-1 handles this signal just fine without loading it down too much. Also, be aware that this point that I am using combines with any PL/DPL you might have programmed into the radio. CSQ and PL/DPL are not separate, which for me is good because I can use the PL/DPL decode from the radio's processor without having to provide my own outboard decoder board.
Again, I apologize for not having a picture available to show for this. I found the COR point for this from repeater-builder.com.. I did not find it on my own. Oh, and as for getting the rig to receive down to 902, I simply unsoldered the front end filters off the board and jumpered them out. I easily have .25uv at 902.7125.. I added an ARR preamp to it just to give it a little boost.
Anyway, if you need further info on how I did any of this, please don't hesitate to ask. Unlike others who would rather keep things like this to themselves, I am most willing to be of help!
73,
Steve
KA4YMY
- Pop the top cover off the radio.
- With the front of the radio towards you, look on the left hand side. There is a fancy looking rectangular flat pack chip on the left, mine has the Intel brand stamped on it.
- There are some small round thru-hole connections just above that chip going towards the back of the circuit board to the 16 pin connector. The COR signal is available from one of those thru-hole connections. It isn't but maybe 1/4 inch up from the Intel chip. My best suggestion is to grab your voltmeter, run a signal into your radio until you find this point. Be aware that you have to use very fine wire to make connection to this thru-hole point. I modified my receive radio by disconnecting the 0 ohm resistor at the 16 pin accessory connector, pin 14 (mic hook) and ran my COR signal to that pin instead. This way, I have COR coming out the back. And by the way, I did not have to add a buffer transistor to utilize this signal. I'm using a Link-Comm RLC-1 controller. The RLC-1 handles this signal just fine without loading it down too much. Also, be aware that this point that I am using combines with any PL/DPL you might have programmed into the radio. CSQ and PL/DPL are not separate, which for me is good because I can use the PL/DPL decode from the radio's processor without having to provide my own outboard decoder board.
Again, I apologize for not having a picture available to show for this. I found the COR point for this from repeater-builder.com.. I did not find it on my own. Oh, and as for getting the rig to receive down to 902, I simply unsoldered the front end filters off the board and jumpered them out. I easily have .25uv at 902.7125.. I added an ARR preamp to it just to give it a little boost.
Anyway, if you need further info on how I did any of this, please don't hesitate to ask. Unlike others who would rather keep things like this to themselves, I am most willing to be of help!
73,
Steve
KA4YMY
I stand corrected. It wasn't from repeater builder, it was from this forum. It has been quite some time since I have seen this info, but this looks like the proper thread:
http://batboard.batlabs.com/viewtopic.php?t=26607
The only downside now is that the pics don't seem to be available anymore. I'll see if I can try to get some pictures taken of my own equipment in the near future, I will share what I have done to make mine work.
Steve
http://batboard.batlabs.com/viewtopic.php?t=26607
The only downside now is that the pics don't seem to be available anymore. I'll see if I can try to get some pictures taken of my own equipment in the near future, I will share what I have done to make mine work.
Steve
OK, I borrowed a neighbor's camera (it's a very cheap one!) and YES, I know it's blurry but it's best I can offer, guys. No access to a macro lens for this.. Hopefully though, it will at least give you a general idea of where to find this COR point.
Yeah, I know it isn't much and it's hard to see, but I would think that this will direct you to the general area that I am trying to refer you to. As stated, it is a round thru-hole going to the underside of the pc board.
If someone in the group has access to a better quality camera with a macro lens that will allow up-close shots for something like this, find this point, mark it and snap a shot for the rest of the group.
Hope this helps just a little more, for what it's worth to you.
Steve
Yeah, I know it isn't much and it's hard to see, but I would think that this will direct you to the general area that I am trying to refer you to. As stated, it is a round thru-hole going to the underside of the pc board.
If someone in the group has access to a better quality camera with a macro lens that will allow up-close shots for something like this, find this point, mark it and snap a shot for the rest of the group.
Hope this helps just a little more, for what it's worth to you.
Steve
Jonathan where can I find information on the Maxar DPL board you are talking about sounds like what I need for a project I am working onJonathan KC8RYW wrote:Time for "plan B".
Program the GTX for CSQ on recieve.
Take a Maxar DPL board, connect it to 16-pin connector pin 11 (Flat RX Audio).
Feed COS from the Maxar DPL board to the IRLP controller.
thanks
Joel KE7JOI
Re: GTX Mobile PL/DPL dectect output line?
Thats the same type of application I had..Jonathan KC8RYW wrote:Anyone know where?
I'm trying to use a GTX mobile for an IRLP RoIP node.
There is an active low audio PA enable point on the board:
http://www.qsl.net/kb9mwr/projects/900m ... 0a-COR.jpg
GTX 900 COR
I found this in the AR902MHz Photo Albums>Miscellaneous
http://ph.groups.yahoo.com/group/AR902M ... w/c7ce?b=8
It shows Squelch Detect high on receive location.
Sorry I can't copy photo into this msg.
Ken
http://ph.groups.yahoo.com/group/AR902M ... w/c7ce?b=8
It shows Squelch Detect high on receive location.
Sorry I can't copy photo into this msg.
Ken
