M1225 connection to old paging encoder

[mt1000ff]

I am needing information on how to connect an old Motorola paging encoder to a M1225 radio. There are two numbers on the bottom of the encoder; one is NLN 6359B, the other is NLN 1013B. There are two rows of four termanal screws across the back. #1 is jumpered to #2 and output leads are connected to #s 2, 3, and 4. This encoder was operational to another brand radio prior to a lighting strike that took out the radio. The encoder "appears" to be still operational. I know I will have to get a 16 pin plug for the rear, but I dont know which out puts go to which pins on the radio. This antique is not used for emergency paging, the county takes care of that. It is only used for administrative paging only. Thanks for your help.

[wavetar]

I have no info on the product itself, but it should be easy to figure it out with 3 wires.

There will be a ground lead...I'm thinking #1, as it's jumpered to #2, which is likely "PTT common". You didn't say how the encoder was powered, but if it's with a 12-volt DC connection, you can confirm the ground very easily by measuring a short from the DC ground to one of the terminal screws. Once you've determined ground, you then operate the encoder to see which of the other screws shorts to ground when the encoder is sending the tones...this is to key the radio. The remaining screw will be the tone audio.

[mt1000ff]

Thank you for your help. The old encoder is powered by 110 AC, weighs a ton. How would I put this into the M1225? I know some of the pins are set in the programming software.
Tim

[wavetar]

Once you determine the outputs, they would connect to the M1225 like so:

Code: Select all

Ground ----> pin 7
PTT -------> pin 3
tones -----> pin 5

None of these pins are programmable in the M1225, it is the default hardware state of them. You may have to go into the accessory pin programming to play with the "pre/post limiter" setting to get the tones to go through properly on pin 5...I haven't hooked an encoder to an M1225 to be sure or not.

[mt1000ff]

Thank you sir:
This is what I was needing. I have online purchased the accessory plug for the back of the radio. When it comes in I will use the above and try to get on the air with our tones.

Tim

[mt1000ff]

Thanks again:
With your help and I found a encoder manual on ebay, I got her on the air. First tone is "scratchy" but it sets off the pagers. According to the manual this thing is about 35 years old. Since its use is rare and non emergency, it will last untill the county decides how far they are going to revamp due to rebanding.

Tim