GM300 repeater setup/programing

[EPC_1111]

We are trying to set up some repeaters with GM300s. I have one RICK and a few of the radio-radio interface cables.

How do we program the accesory cable to make it work as a repeater? I believe pin 8 is programmed for COR, but have lost my notes and am having issues searching. Mahalo

[Doug]

If you set receive radio pin 8 as cor then you would have to have S2-2 as off and S2-3 as on other than that there's nothing else that needs changing as far as the radio goes, unless your going to use the setup/knock down features.
Doug

[laramiecountyCERT]

I dont recommend running the GM300 full out on TX either as they are not designed to be a full duty repeater. We have one for my work and they are turned down to 15W and then bumped up to a full 30W with the antenna to avoid burning out the finals in the rigs.
This might help a bit as well:

1. First, read the radio with RSS. Go to the Radio Wide Configuration screen (F2). Here, (if the radio has an expanded logic board), you will find a choice of F9. Press F9. This takes you to the Accessory Connector Configuration screen, where the definitions of pins 4,6,8,9,12 & 14 can be viewed or changed. Check to see if Pin 8 is already set as: (Description = PL/DPL & CSQ Detect; Data Direction = Output; Debounce = No; Active Level = Low). If yes, this radio can be used with the RA-2. If no, change Pin 8 to these parameters and write the change back to the radio. Now it can be used.

I have read my radio with RSS, but I do not see any option for changing the accessory connector (F9 does not appear on the Radio Wide Configuration screen). What now?

2. It might still be usable. On some 16-pin models, Pin 8 provides an active-low COS output, even though the accessory connector is not fully programmable. Check Pin 8 with a dc voltmeter (positive probe to Pin 8, negative probe to ground). Do you see approximately +5 volts on Pin 8 with the receiver squelched, and less than 0.1 volts when receiving a signal with the correct PL? If yes, this radio can be used with the RA-2. No? Go to step 3.

3. Repeat the measurement from step 2, but this time, use a pull-up resistor to +12v (wrap one end of a 10k resistor around the positive voltmeter probe and connect the other end of the resistor to +12v). Reconnect the positive voltmeter probe to Pin 8. You should now see +12 volts on Pin 8 with the receiver squelched. Does this drop to less than 0.1 volts when receiving a signal with the correct PL? If yes, this radio can be used with the RA-2.

Where do I find Pin 8 on the accessory connector?

(16-pin radios): With the radio upside down and the accessory jack facing you, Pin 8 is on the bottom row, 4th pin from the right.

I've measured the voltage on Pin 8 as described in steps 2 and 3, but I am not seeing an active-low transition when the radio unsquelches. What now?

On some radios, even though the accessory connector is not fully programmable, Pin 8 can be made to provide an active-low COS output, by programming the radio in Repeater Mode (see step 4).

4. From the Main Menu, select F3 (GET/SAVE). Do you see an option of F6 (Change to Repeater Mode)? If so, try the following steps:

Press F6 (Change to Repeater Mode).

Press F2 (Read Repeater), and then press F10 for a Generic Repeater.

Press F10 again to skip the transmit radio. Connect the programming cable to the receive radio and press F2 to read it. Keep pressing F2 until you reach the GET/SAVE menu. Then press F10, followed by F4. You will now be back at the CHANGE/VIEW menu, in Repeater Mode.

Press F5 (Mode Configuration). Set the repeater type to Generic and enter your receive frequency and PL. There is only room to enter ONE (receive only) frequency & PL on this screen, but that's okay.

Write this change back to the radio. This should cause Pin 8 to provide an active-low COS output (verify this with a voltmeter as described in steps 2 & 3 above).

After you've programmed the radio in Repeater Mode (to get Pin 8 to behave as active-low COS), return to the GET/SAVE menu and change it back to Radio Mode, which will allow you to program additional frequencies. Pin 8 will remain set as active-low COS.

Let me know if that works

[EPC_1111]

What we ended up doing was programming one radio as RICK Receive and one as RICK Transmit. This coupled with an ebay style RICKless cable made it work just fine.

Somewhere I believe I read something about pin 14 being TOR, is this correct?

[Doug]

On some of the radios with expanded logic boards it is possible to change pin 14.(radios with a high signaling option) Off the top of my head I don't remember the different options but the ones I've run across they set pin 14 for cor and usually pin 8 as pl/dpl detect.

[laramiecountyCERT]

I think the GM300 can be changed to have the pins changed on pins will have to boot the old DOS machine to make sure.