Midland 70-1341, Руководство по обслуживанию

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PREPARATION
70-1341/1344/1441/1444
7. Adjust RV401 for a deviation of ±750 Hz ±10 Hz
for wide band, or ±375 Hz ± 10 Hz for narrow
band.

Quadrature Detector
4. No adjustment for the quadrature is required.
8. Enter DCS code +023.

First IF
9. While observing recovering modulation on an
oscilloscope, fine tune RV401 for a square DCS
wave form as shown in
Figure 2 – 1 .
5. Apply enough on-channel carrier modulated by
1 kHz tone at ±3 kHz (wide-band) or ±1.5 kHz
(narrow band) deviation to maintain 12 to 15 dB
SINAD. Adjust L215, L216, and L217 for
minimum RF level required to maintain 12 dB
SINAD.
10. Set CTCSS frequency to 250.3 Hz. Adjust
RV401 for 750 Hz ±100 Hz deviation.

DTMF

Squelch
11. Clear the CTCSS tone, then initiate transmit
using the programmer.
6. Press the Channel/Mode knob until “SQL”
appears in the display. Rotate the
Channel/Mode Knob until “80” appears in the
display.
12. Adjust DTMF deviation to ± 2.0 kHz ±10 Hz for
wide band, or ±1.0 kHz ±10 Hz for narrow band,
using the programmer.
7. Adjust Squelch range RV402 fully counter-
clockwise.
RECEIVER ALIGNMENT
8. Apply 0.5

V of unmodulated on-channel RF
signal to the 50

antenna connector.
1. Change the RX test frequency to 148.2 MHz for
A-Band radios, 162.30 MHz for B-band.
9. Adjust Squelch range RV402 clockwise just until
squelch opens (audio on).

First Injection
2. No adjustment for first injection is required.

Preselector Alignment
3. No adjustment for the preselector (L201, L202,
L204, L205, L206 and L207) is required.
CORRECT INCORRECT INCORRECT
Figure 2 - 1
2 - 5