radios:gm350
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Motorola GM350
The Motorola GM350 is a PMR radio which can easily be used in the amateur bands. Versions are available for low-band VHF (4m), VHF (2m) and UHF (70cm), and can often be picked up for as little as £20. More information on the radios can be found here.
Physical information
The radio is 168 × 44 × 180 mm (6.61 × 1.73 × 7.09 in) and weighs 1.7kg (3.8lbs).1) It has a threaded hole on each side for mounting.
Requirements
The radio will accept a DC voltage between 10.8 and 15.6 volts. It requires an antenna with an impedance of 50 ohms.2)
Accessory Port
On the rear of the radio is found the antenna socket (BNC), the power socket, and the accessory port. The accessory port has sixteen pins, explained below3):
Pin diagram:
2 4 6 8 10 12 14 16 1 3 5 7 9 11 13 15
| Pin | Purpose | Description | NinoTNC pin |
|---|---|---|---|
| 1 | EXT SPKR - | -ve connection for an external speaker | |
| 2 | EXT MIC AUDIO | an alternative microphone signal input (note only one microphone should be used at a time) | |
| 3 | MIC PTT | radio PTT | |
| 4 | PRG O/P | re-assignable output (from within config s/w) | |
| 5 | FLAT TX AUDIO | for injecting unfiltered audio into the radio | |
| 6 | PROG I/O 6 | used for programming or tuning the radio - accesses the radio's SCI serial bus | |
| 7 | GROUND | ground for both analogue and digital signals | |
| 8 | PROG I/O 8 | re-assignable digital i/o (from within config s/w) | |
| 9 | PROG INPUT 9 | re-assignable digital input (from within config s/w) | |
| 10 | IGNITION CONTROL | connected to the ignition line of a vehicle, this will automatically turn the radio on when the ignition is turned on | |
| 11 | RX AUDIO | analogue output for taking audio out to a TNC, etc. Note this needs configured from within the software | |
| 12 | PROG I/O 12 | re-assignable digital i/o (from within config s/w) | |
| 13 | SW A+ SENSE | unsure what this is for! | |
| 14 | PROG I/O 14 | re-assignable digital i/o (from within config s/w) | |
| 15 | RSSI | received signal strength indicator (analogue voltage) | |
| 16 | EXT SPKR + | +ve connection for an external speaker |
3)
This information is taken from the user manual - see https://obrazki.elektroda.pl/8715300300_1347271923.gif and http://batlabs.com/gm350.html
radios/gm350.1721948852.txt.gz · Last modified: 2024/07/25 23:07 by gm5aug