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GENERAL INFORMATION
1-5
November 1998
Part No. 001-7600-001
7610 (VHF) AND 7640 (UHF) MOBILE SPECIFICATIONS
The following are general specifications intended for use in testing and servicing this transceiver. For current
advertised specifications, refer to the specification sheet available from your sales representative. Values are
typical and are subject to change without notice.
GENERAL
Frequency Range
VHF: 146-174 MHz
UHF: 400-430 MHz, 450-470 MHz, 470-490 MHz, or 488-512 MHz (some
performance degradation from 488-490 MHz with 488-512 MHz models)
Operating Modes
Conventional (non-trunked), Tone and digital Call Guard® squelch
Channels
32 maximum (2 banks x 16 channels available)
Transmit/Receive Separation
Any frequency within the range
Channel Spacing (dual IF Models) VHF - 12.5 kHz (narrow band) and 30 kHz (wideband)
UHF - 12.5 kHz (narrow band) and 25 kHz (wideband)
Maximum Deviation
12.5/15 kHz channel spacing - 2.5 kHz maximum
25 kHz channel spacing - 5.0 kHz maximum
Frequency Stability
5.0 PPM (VHF), 2.5 PPM (UHF) from –22° to +140° F (–30° to +60° C)
Dimensions (w/o controls)
1.6” H x 5.5” W x 6.7” D (4.1 cm x 13.9 cm x 17.0 cm)
Weight
2 lb. 11 oz. (1.22 kg)
Supply Voltage
13.6 volts DC nominal (12-volt, negative ground vehicle electrical system)
Current Drain (maximum)
Standby - 200 mA standby
Receive (rated audio out) - 700 mA
Medium Tx Power - 6.0 A (VHF), 7.0 A (UHF)
High Tx Power - 15 A max/10 A typ (VHF), 11 A max/8 A typ (UHF)
FCC Compliance
Parts 15 and 90
RECEIVER
Sensitivity (12 dB SINAD)
0.25 µV
Selectivity
70 dB at 25 kHz, 60 dB at 12.5 kHz
Spurious and Image Rejection
70 dB
Intermodulation
65 dB
Hum and Noise
46 dB at 25 kHz, 40 dB at 12.5 kHz
Maximum Frequency Spread
Any spread within the range
Audio Power Output
3.5 W into 4-ohm load
Audio Distortion
Less than 10% at 1 kHz with 60% deviation
Audio Response
+2, –8 dB at 6 dB per octave de-emphasis
RF Input Impedance
50 ohms
TRANSMITTER
RF Power Output
VHF: 45W (high), 25W (low 1), 4.5W (low 2)
UHF: 35W (high), 20W (low 1), 3.5W (low 2)
Spurious and Harmonic Emissions 70 dB
FM Hum and Noise
46 dB at 25 kHz, 40 dB at 12.5 kHz
Audio Modulation
12.5 kHz - 11K0F3E, 25 kHz - 16K0F3E
Audio Distortion
Less than 5% at 1 kHz with 40% modulation
Audio Frequency Response
+2, –8 dB at 6 dB per octave pre-emphasis
Maximum Frequency Spread
Any spread within the band
RF Output Impedance
50 ohms
Duty Cycle
20% TIA
Summary of Contents for 761X
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Page 11: ...GENERAL INFORMATION 1 6 November 1998 Part No 001 7600 001 NOTES ...
Page 43: ...PROGRAMMING 4 18 November 1998 Part No 001 7600 001 This page intentionally left blank ...
Page 87: ...UHF 7640 EXPLODED VIEW 7 22 November 1998 Part No 001 7600 001 FOLDOUT VHF Exploded View ...
Page 90: ...8 3 November 1998 Part No 001 7600 001 VHF 7610 MAIN BOARD BOTTOM VIEW FOLDOUT ...
Page 91: ...8 4 November 1998 Part No 001 7600 001 VHF 7610 MAIN BOARD TOP VIEW ...
Page 94: ...8 7 November 1998 Part No 001 7600 001 UHF 7640 MAIN BOARD BOTTOM VIEW FOLDOUT ...