Possible to operate a gr1225 without control head?

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witthoft
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Possible to operate a gr1225 without control head?

Post by witthoft »

I was wondering if after I program the radio with the control head if it were possible to use just the r1225 as a repeater, or does it need the control head? If so, how would it be done? Are there any drawbacks to this, other than not having a local mike? Would you lose the "repeat enabled", or the "mic on hook" functions? Thanks for your help.
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Will
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Re: Possible to operate a gr1225 without control head?

Post by Will »

witthoft wrote:I was wondering if after I program the radio with the control head if it were possible to use just the r1225 as a repeater, or does it need the control head? If so, how would it be done? Are there any drawbacks to this, other than not having a local mike? Would you lose the "repeat enabled", or the "mic on hook" functions? Thanks for your help.
Yes, the GR1225 and other variants do not need the control head to operate as a repeater. You do have to add a jumper to the control connector on the RF unit to switch the A+ on.

No drawbacks, we run all of the ones we service without the control heads. One advantage is no one can fool with the knobs...

We have a test cable that plugs into the front of the RF chassis and gives the capability to program, use a test mic (GM300 mob mic), and listen to the speaker.
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witthoft
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Re: Possible to operate a gr1225 without control head?

Post by witthoft »

Will-- could you tell me exactly the pins to jump to set this up? Is it where the ribbon cables connect to the front of the radio? Thanks for your help.
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Re: Possible to operate a gr1225 without control head?

Post by Will »

witthoft wrote:Will-- could you tell me exactly the pins to jump to set this up? Is it where the ribbon cables connect to the front of the radio? Thanks for your help.

J 8 is a 15 pin connector, male pins on the front of the RF unit. Pin one is closest to the Receiver antenna connector, pin 3 is blank. Pin 8 is A+, pin 7 switched A+, short these two pins with a Berge jumper. ( Like the two pin jumpers on the computer motherboards).

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witthoft
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Re: Possible to operate a gr1225 without control head?

Post by witthoft »

Great. Thanks for the help!
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Bill_G
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Re: Possible to operate a gr1225 without control head?

Post by Bill_G »

Good info Will. Thanks!
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Re: Possible to operate a gr1225 without control head?

Post by n8vjp »

We have a test cable that plugs into the front of the RF chassis and gives the capability to program, use a test mic (GM300 mob mic), and listen to the speaker.
Hopefully Will is still monitoring this thread.

I have an R1225 without the head using the jumper method, but now need to reprogram it. Could you share your pinout for the test cable to get me from ribbon to RJ45?
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Re: Possible to operate a gr1225 without control head?

Post by lspdusnure »

n8vjp wrote:
We have a test cable that plugs into the front of the RF chassis and gives the capability to program, use a test mic (GM300 mob mic), and listen to the speaker.
Hopefully Will is still monitoring this thread.

I have an R1225 without the head using the jumper method, but now need to reprogram it. Could you share your pinout for the test cable to get me from ribbon to RJ45?
hi just put the head back on and program it then remove it and re install the jumper. easiest way.
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n8vjp
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Re: Possible to operate a gr1225 without control head?

Post by n8vjp »

We don't have the head.
lspdusnure
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Re: Possible to operate a gr1225 without control head?

Post by lspdusnure »

get a program cable for the 16 pin option plug on rear of radio. i have control heads of sale on ebay for these cheep.
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Mikey
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Re: Possible to operate a gr1225 without control head?

Post by Mikey »

I have usd a Standard GM300 Head to program a R1225 Before, works just the same!
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Re: Possible to operate a gr1225 without control head?

Post by lspdusnure »

that makes sense cause a gr1225 repeater has almost same as gm300 logic board so that's a good deal.
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Re: Possible to operate a gr1225 without control head?

Post by n8vjp »

lspdusnure wrote:get a program cable for the 16 pin option plug on rear of radio.
Thanks for the hint that the accsy plug could also be used. Doing some more Googling, I think I found my answer.
http://www.batlabs.com/gm350.html

RJ45 8pin <----->16pin Accessory Function(Acc)
7 Orange <-----> 6 BUS+
4 Green <-----> 7 Ground
1 Brown <-----> 13 SW B+
3 Yellow <-----> 14 Hook
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Re: Possible to operate a gr1225 without control head?

Post by Will »

lspdusnure wrote:snip gr1225 repeater has almost same as gm300 logic board so that's a good deal.
No the logic and RF boards are totally different in the R1225, not even close.
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Re: Possible to operate a gr1225 without control head?

Post by Will »

The programming SCI+ does not appear on the 16 pin connector.

J8 is the 15 pin connector on the front of the R1225 radio chassis.

So J8: RADIO --------------------------------------- RJ45 Jack MIC/Prgm
pin 3 is missing
pin 4 RX audio output, low level ------------------- pin 1
pin 7 jumper to 8 SW B+
pin 8 jumper to 7 B+
Pin 9 is SCI+ the programming pin ---------------- pin 2
Pin 12 is ground ------------------------------------- pin 5
pin 13 is PTT ---------------------------------------- pin 3
pin 14 is Mic hi -------------------------------------- pin 4
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Re: Possible to operate a gr1225 without control head?

Post by n8vjp »

Perfect, thanks Will! I knew by posting the link to the GM350, someone would be able to correct it!
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Mikey
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Re: Possible to operate a gr1225 without control head?

Post by Mikey »

Well the Logic Boards may be different between the GM300 and the R1225 but the GM300 control head will plug right in to where the ribbon cable plugs and give you everything you need to turn it on and program it, then just take the head off and slip the jumper on the pins to power the repeater and your good to go!


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Re: Possible to operate a gr1225 without control head?

Post by TWEMARS »

Hi Guys:

Lets set a few things straight here.

With the control head missing you will not be able to channel steer the radio from the rear connector. You can use the GM300 volume board to program and even run an R1225 but the DISPLAY BOARDS are different.
I have a Halcyon TIMS. It has an audio spectrum analyzer.
I have an IFR 1200. It has an audio distortion analyzer.
I can test and alter the audio response and distortion of my analog radio system to make it sound better.
I have a pair of socks.
Why would I want to put them in my mouth just so I could sound like I'm using a DMR radio?
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d119
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Re: Possible to operate a gr1225 without control head?

Post by d119 »

HOLY ANCIENT THREAD BATMAN! Way to bring back a 7 year old thread. Where's my controller?!?!? ;)
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