Users Manual
Specifications
9-3
● CH70 Watchkeeping Receiver
Receiving frequency 156.525 MHz (CH70)
Receiving system Double superheterodyne
1st IF 50.85 MHz
2nd IF 450 kHz
Local oscillation frequency Receiving frequency + 50.85 MHz
Local oscillation method Frequency synthesizer
Local oscillation freq. variance ±10 x 10
-6
or less
Sensitivity 1% or lower symbol error rate at 0dBV
Selectivity 6dB bandwidth: 12kHz or more, 70dB selectivity: 25kHz or less
De-emphasis characteristics 6dB/oct, within +1dB, -3dB
Co-channel selectivity SER is less than 10
-2
when -8 dB of interference is added
Adjacent channel selectivity 4.47 mV during interference input; 1% or lower CER
Desensitization effect 4.47 mV during interference input; 1% or lower CER
Spurious response 4.47 mV during interference input; 1% or lower CER
Intermodulation characteristics 2.5 mV during interference input; 1% or lower CER
Blocking characteristics BER is less than 10
-2
when 90 dB of interference is added
Radiation 9 kHz - 2 GHz: 2 nW or less
● DSC/ATIS Modem
Modulation rate 1200 baud (within 600 Hz ± 30 ppm)
Modulation method FSK
Modulation index DSC: 2.0 ±10 % or less
ATIS: 1.0 ±10 % or less:
Mark frequency (Y) 1300 Hz ±10 Hz or less
Space frequency (B) 2100 Hz ±10 Hz or less
DSC protocol ITU-R Recommendation M.493-14 (Class A)
DSC operation standards ITU-R Recommendation M.541-9, M.689-2, M.821-1, M.1080-0
ATIS protocol, standards ETSI EN 300 698 V2.2.1
● Display control panel
Microphone input impedance 2.2 k balanced (NQW-980 use)
Standard modulation input -40 dBm
Audio output Built-in speaker (4 ): 6 W or more
Handset phone (150 ): 1 mW or more
LCD 5-inch TFT color, 800x480 pixels, LED backlight,
Maximum brightness 1000 cd/m
2
Operation buttons Touch panel, power button, DISTRESS button, volume control,
SQ control