Furuno DSC-60 Service Manual page 76

4. RX PCB
This is the test of RX board (05P0703).
To facilitate the adjustment and checking of PLL synthesizer and receiving sensitivity of RX board, the
setup frequencies are registered.
Pressing [ENT] key reveals the following screen.
SYN ADJ CH and FREQ SYN ADJ CH and FREQ SYN ADJ CH and FREQ SYN ADJ CH and FREQ SYN ADJ CH and FREQ
The setup frequency to adjust PLL synthesizer is registered. The number of registrable channels are
"16".
When a channel, registered as follows, is specified, the frequency data is setup on RX board.
The method of setting the channels is:
- 1. Select SYS ADJ CH and press [ENT] key. Then, select a channel with the up/down cursor
keys and press [ENT] key.
- 2. Select FREQ and press [ENT] key. Then, input the frequency with the numeric keys and
press [ENT] key.
SEN CHK CH and FREQ SEN CHK CH and FREQ SEN CHK CH and FREQ
SEN CHK CH and FREQ SEN CHK CH and FREQ
To check the receiving sensitivity of every frequency, the setup frequency is registered. The number of
registrable channels are "12".
When a channel, registered as follows, is specified, the frequency data is setup on RX board.
The method of setting the channels is:
- 1. Select SNS CHK CH and press [ENT] key. Then, select a channel with the up/down cursor
keys and press [ENT] key.
- 2. Select FREQ and press [ENT] key. Then, input the frequency with the numeric keys and
press [ENT] key.
TEST SIG. TEST SIG. TEST SIG.
TEST SIG. TEST SIG.
Turning ON/OFF the 18 MHz test signal of RX board is tested.
FREQ SWEEP FREQ SWEEP FREQ SWEEP
FREQ SWEEP FREQ SWEEP
This test sweeps specified frequencies to check spurious receiving frequencies.
To setup the sweep frequencies, press [ENT] key, input the frequencies with the up/down cursor keys,
and then press [ENT] key.
Select a step frequency with the lift/right cursor keys, and then, select sweep frequencies corresponding
to the step frequency with the up/down cursor keys.
As soon as a frequency is changed, the frequency data is sent to RX board.
**** RX PCB test * * *
SYN ADJ CH : 01 (01 - 16)
FREQ : 12,345.67 kHz
SEN CHK CH : 01 (01 - 12)
FREQ : 12,345.67 kHz
TEST SIG. : OFF
FREQ SWEEP : 12,345.67 kHz
5-15
3. Test through the Setup Menu