Motorola GP360 Service Information

1-4 THEORY OF OPERATION
A MOSFET Q416 switches in the LiO supply when Vdd is removed. Q416 also provides isolation
from BOOT_CTRL function in the event of radio program flashing. The 3.3V regulator charges the
Lithium battery.
3.4 ModB/Vstby Supply
The supply to the ModB/Vstby pin varies depending on the conditions listed in Table 1-2.
3.5 Audio/Signaling Architecture
( Refer to Figure 1-2 and the ASFIC/ON_OFF and Audio Power Amplifier schematic diagrams )
The audio/signalling/filter/companding IC (ASFIC_CMP) and the audio power amplifier, shown in
Figure 1-2, form the main components of the audio/signalling architecture section of the controller
board. Inputs include a 16.8 MHz clock from the synthesizer, recovered audio and squelch, MCU
control signals, and external or internal microphones. Outputs include a microprocessor clock (uP),
modulator output to the synthesizer, and amplified audio signals to an internal or external speaker.
Table 1-2 ModB/Vstby Supply Modes
Condition Circuit Operation
Radio On Vdd supply voltage via CR411
Radio Off • Vdd turned off
• Q416 gate pulled low by R462
• Q416 switched on
• U410 supplies 3.2V to ModB/Vstby
Primary battery removed • Vdd turned off
• Q416 gate pulled low by R462
• Q416 switched on
• Lithium battery provides 3.2V to ModB/Vstby
Flash Mode • Boot_Ctrl line pulled low
• ModA & ModB go low
• Processor in boot-strap mode

Motorola GP360 Specifications

Battery

battery life with standard high capacity NiMH battery low power	11 hours
battery life with standard high capacity NiMH battery high power	8 hours
battery life with ultra high capacity NiMH battery low power	14 hours
battery life with ultra high capacity NiMH battery high power	11 hours
battery life with NiCD battery low power	12 hours
battery life with NiCD battery high power	9 hours
battery life with Li-lon low power	11 hours
battery life with Li-lon high power	8 hours

Operating Environment

operating temperature	-20°C to +55°C
sealing	Withstands rain testing per MIL STD 810 C/D/E and IP54
shock and vibration	Protection via impact resistant housing exceeding MIL STD 810-C/D/E and TIA/EIA 603
dust and humidity	Protection via environment resistant housing exceeding MIL STD 810 C/D/E and TIA/EIA 603

Transmitter Specifications

frequencies full bandsplit VHF	136-174 MHz
frequencies full bandsplit UHF	403-470 MHz
channel spacing	12.5/20/25 kHz
frequency stability	±2.5 ppm
power VHF	1-5W
power UHF	1-4W

Receiver Specifications

frequencies full bandsplit VHF	136-174 MHz
frequencies full bandsplit UHF	403-470 MHz
channel spacing	12.5/20/25 kHz
frequency stability	±2.5 ppm
sensitivity (12 dB SINAD) EIA	0.25 µV typical
sensitivity (20 dB SINAD) EN	0.50 µV typical

Weight and Dimensions

dimensions with standard high capacity NiMH battery	137 x 57.5 x 37.5 mm
dimensions with ultra high capacity NiMH battery	137 x 57.5 x 40.0 mm
dimensions with NiCD battery	137 x 57.5 x 40.0 mm
dimensions with Li-lon battery	137 x 57.5 x 33.0 mm
weight with standard high capacity NiMH battery	428 gm
weight with ultra high capacity NiMH battery	508 gm
weight with NiCD battery	458 gm
weight with Li-lon battery	358 gm