2. TECHNICAL SPECIFICATIONS
A. GENERAL
1) Frequency Range
: 462.5500 ~ 462.7250 MHz
2) Modulation Type
: 16KOF3E (FM)
3) Channel capacity
: 15 channels
4) Channel spacing
: 25KHz
5) Power Supply
: DC 4.8V, Ni-Mh Rechargeable Pack
6) Current Drain
: Transmitter (2W ) ----- <1100mA (Ni-Mh Rechargeable Pack)
Receiver (0.5W) ---------<300mA
7) Battery Life
: 8hrs. talk time;
20 hrs. stand-by time
8) Operating Temperature
: -20
°
C to +60
°
C
9) Dimensions
: 65(H) x 132(W) x 39(D) mm
10) Weigh
: 8 oz.(with battery)
B. TRANSMITTER
1) Power Output
: 2W
2) Frequency Stability
: Better than +/- 5ppm within operating temperature
3) Hum & Noise : -40dBc(with 300Hz to 3KHz audio filter)
4) Spurious & Harmonics
: -60dBc
5) Audio Distortion
: Less than 5% (1KHz tone 6 0% modulation)
C. RECEIVER
1) Sensitivity (12dB SINAD)
: 0.25Uv(-119dBm SINAD)
2)
Selectivity
:
-60dB
3) Inter-modulation
: -60dB
4) Spurious and image rejection : -60dB
5) Maximum Audio Output
: More than 200mW
6) Audio Distortion
: less than 5%
3. THERORY OF OPERATION
INTRODUCTION
GMRS X1 is a micro size15 channel portable FM transceiver constructed with a microprocessor controlled,
temperature compensated Phase Locked Loop (PLL) frequency synthesizer. The radio features a double
conversion receiver and a direct FM transmitter modulator. A special integrated circuit provides support to
sub-audible signaling (CTCSS) and most of the receiving parts are switched off periodically in the power saver
mode to reduce battery current drain during standby.