Radio Shack TRC-447, Руководство по обслуживанию

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CB TRANSMITTER PORTION
Item Unit Nominal Limit
Frequency tolerance 25 °C 13.8 V Hz
±
200
±
1300
RF Power output W
−
4
AMC range 50% to 100% modulation dB 45 35
Modulation frequency response Lower frequency 450 Hz dB
−
3
−
10
Upper frequency 2500 Hz dB
−
3
−
10
Microphone sensitivity 1 kHz, 50% Mod. mV 4 10
Modulation distortion 1 kHz, 80% Mod. % 3 8
Battery drain at No modulation mA 900 1300
at 80% modulation mA 1300 1900
RF Power output at 12 V W 2.7 2.2
Modulation attack time mSec 100 300
Modulation release time mSec 800 500
CB RECEIVER PORTION
Maximum sensitivity
µ
V 0.5 1
Sensitivity for 10 dB S/N
µ
V 0.5 1
AGC Figure of merit 50 mV for 10 dB change in audio output dB 90 75
Threshould squelch sensitivity
µ
V 0.5 1
Tight squelch sensitivity
µ
V 1000 250 ~ 4000
Adjacent channel selectivity at
±
10 kHz dB 50 40
Spurious rejection ratio dB 45 30
Image rejection ratio (
−
910 kHz) dB 65 55
IF rejection ratio 10.695 MHz dB 60 50
455 kHz dB 90 60
Audio output power Maximum 8-ohm W 5.5 4.0
10% Distortion 8-ohm W 4.0 3.5
Audio frequency response Lower frequency 450 Hz dB
−
3 -10
Upper frequency 2500 Hz dB
−
3 -10
THD at 500 mW audio output 1 mV 30% input % 3 5
Signal to noise ratio at 1mV dB 40 35
Oscillator on voltage V 5 11
Battery drain at No signal mA 300 350
at Maximum AF output mA 1000 1500
RF gain control range at 1
µ
V reference dB 30 20
S-meter sensitivity at S-9
µ
V 100 50 ~ 200
WEATHER RADIO SECTION
Sensitivity at 2.0
µ
V Input dB SINAD 27 15
THD at 500 mW audio output
Input 1 mV
±
3 kHz deviation % 3 7
Signal to noise ratio at 1 mV dB 45 35
Audio output power Maximum 8-ohm W 5.5 4
10% Distortion 8-ohm W 4 3.5
Digital weather alert sensitivity
Input SAME data (FSK)
±
4.5 kHz dev.
µ
V 0.5 1.0