Dsc Tone Frequency - Furuno FM-8800D Service Manual

6.2.3 DSC Tone Frequency

In the FM-8800 program: INTL Ver.03.01 and after /Russian ver., TONE
selected from a speaker is outputted when TONE TEST is performed in the
"6.2.2 CH70 Output".
In case of the INTL Ver.02.03 and before for the FM-8800 program
No checkpoint in Mark and Space Tone. Therefore, when confirming the tone frequency,
monitor the tone frequency by other VHF transceiver for CH70. The tone frequency
tolerance is within +10 Hz.
In this section, monitoring procedures with FM-8800S, D are described.
Handset
FM-8800S
FM-8800D
Procedure
*** FM 8800S/D preparation on the monitor side ***
1. Connect the frequency counter to the SP line.
2. Any channels may be selected.
3. Call up the option menus. Refer to page 4-1.
- Make a jumper connection between #2 and #15 on [Printer] port
- Or, jumper connection between #25 and #26 of IF-8810
- Press [MENU] -> SYSTEM -> [ENT] -> Input the password
4. Select T/A and press [ENT] key. Pop-up menus will appear as below.
CH70 is automatically received by CH70 RX board when going into this mode.
And the decoded CH70 signal is outputted to the SP.
DSC RX TEST
OUTPUT RX DSC DATA
TO NMEA PORT
50 ohm
Dummy
ANT
CH70
CH70 ANT
Fig. 6.2.2 Tone Frequency Measurement Circuit
EXT:ENT
Antenna
For Monitor
ANT
FM-8800S
FM-8800D
CH70 ANT
- MARK: 1300 Hz + 10 Hz
- SPACE: 2100 Hz + 10 Hz
NOTE:
Decoded signals are also
outputted into NMEA-TX on
[IEC61162-1/REMOTE] port by
RS-422 level.
6-5
6.2 Measurement
SP
Freq. Counter