Basic Preseltlngs; 4-L Setting A Frequency - Icom C RP1520 Instruction Manual

BASIC PRESETTINGS
WARNING: DISCONNECT the AC power cable from
the repeater before performing any work
on the repeater.
4-1 SElTING A FREQUENCY
The transmit and receive frequencies can be set by dip
switches on the LOGIC-A UNIT. See p. 18 for the
LOGIC-A UNIT location. See p. 19 for each switch
location.
1) Remove the bottom cover.
l Remove 6 screws on the bottom cover and another
3 screws on each side of the front panel.
2) Setting the PLL reference frequency
l Turn ON S4-1 on the LOGIC-A UNIT to set the PLL
reference frequency for 5 kHz.
l Turn OFF S4-1 on the LOGIC-A UNIT to set the PLL
reference frequency for 12.5 kHz.
Example of setting N-data for receiving
l
Receive frequency
1 st IF frequency
PLL reference frequency : 0.005 MHz (5 kHz)
N-data for = receive frequency - 1 st IF frequency
receiving PLL reference frequency
147.700 - 21.8
0.005
= 25180
Set dip switches (Sl, S2) at the values equivalent to
the obtained N-data.
Example of setting dip switches
Dip N-data
switches
S l - 1 0 +
Sl-7
Sl-5
Sl-4
Sl-3
Total
: 147.700 MHz
: 21.800 MHz (fixed)
value
16384
8192
512
64
16
8
4 (+
25180
3) Setting the PLL Ndata
N-data for= receive frequency- 1 st IF frequency (MHz)
receiving
PLL reference frequency (MHz)
transmit frequency (MHz)
N-data for
transmitting = PLL reference frequency (MHz)
Set the N-data obtained in the above formula by using
the dip switches. Every dip switch has an independent
volume of N-data.
NOTE: Confirm that the dip switches are correctly set,
and apply power to confirm the operating fre-
quency after replacing the bottom cover.
Example of setting N-data for transmiting
l
Transmit frequency
PLL reference frequency
transmit frequency
transmitting =PLL reference frequency
145.025
0.0125
= 11602
Set dip switches (S9, Sl 0) at the values equivalent to
the obtained Ndata.
Example of setting dip switches
Dip
switches
Total
: 145.025 MHz
: 0.0125 MHz (12.5 kHz)
value
8192
2048
1024
256
64
16
2 (+
11602