3-12
WRT-808A (U)
2. Frequency check
Connections
(For connecting the DC power supply, refer to the “Preparations”
on page 3-2.)
Procedure
n
Perform the checking with the Mic input connector (CN101)
short-circuit.
(1) Set the modulation analyzer as follows:
MEASUREMENT:
FM
MEASUREMENT RANGE:
±
40 kHz
HPF:
4 kHz
LPF:
>20 kHz
DE EMPHASIS:
OFF
(2) Check that the frequency counter (resolution : 0.1 Hz
setting) reading is 32.768 kHz
±
1 Hz.
fc
32.768 kHz
V : 10 dB/div
H : 20kHz/div
29
±
1 dB
20 dBm
Procedure
n
Perform the checking with the Mic input connector (CN101)
short-circuit.
(1) Set the spectrum analyzer as follows:
CENTER FREQUENCY (fc):
U64 model:
776.125 MHz
U66 model: 788.125 MHz
U68 model: 800.125 MHz
REFERENCE LEVEL:
20 dBm
FREQUENCY SPAN:
200 kHz (20 kHz/DIV)
RBW (resolution band width): 3 kHz
VBW (video band width):
1 kHz
ATT:
20 dB
(2) Adjust
1
RV201 so that level between carrier frequency
(frequency center level) on spectrum analyzer and tone
signal is within 29 dB
±
1 dB.
2
1
Short-
circuit
XLR 3Pin (male)
- wiring side -
3
Modulation
analyzer
Frequency
counter
RF IN
AF OUT
MM-SMA (J) connector
with SMA-BNC (J) connector
CN402