Sony UWP-V1, Service Manual

Page: 70 / 164

2-50
UWP Series
Notes
Because the audio system of the URX-P2 is output in the
unbalanced system, the noise level can be possibly so high
that the S/N measurement becomes impossible depending
on the measurement system. In such a case, reassemble the
URX-P2 completely and emit the RF output of the signal
generator from the antenna (Part No.1-501-612-13) and
receive the RF signal with the URX-P2 in order to imple-
ment the S/N ratio measurement.
Equipment and Tools
.
Signal generator
. Audio analyzer
. Mic amp (Noise meter) with A-weighted filter
.
Oscilloscope
.
Antenna : (Part No.1-754-575-11 or 1-501-612-13)
Connection
Oscilloscope
Audio
analyzer
MIC
amplifier
Signal
generator
OUTPUT
URX-P2
Antenna “a”
Antenna
(1-501-612-13)
Antenna “b”
Procedure
1. Reassembly URX-P2 completely.
2. Turn on the power of the URX-P2 following the
procedure. (For setting, refer to “Setting the Squelch
OFF mode” on page 2-42. For the power supply, use
the battery.)
3. Set the signal generator output level to 80 dB
u
. (Set
the measurement frequency and other parameters to
the same setup as the ordinary measurement.)
4. Move the antenna connected to the signal generator, in
the periphery of the antenna a of the URX-P2 as
shown in the illustration.
5. Confirm that the decimal digit indicator that is located
in between the first digit and the second digit from the
left-most end of the LCD indicator lights on.
n
If the decimal digit indicator does not light on, confirm
tat is lights when the antenna connected to the signal
generator is moved to front, end, right or left slightly.
6. Set “modulation” of the signal generator to OFF.
Confirm that the S/N ratio in this setup is 62 dB or
more (A-weighted).
7. Set “modulation” of the signal generator to ON.
8. Set the audio analyzer to the distortion measurement
mode.
9. Confirm that distortion is less than -40 dB (1% or less).
10. Move the antenna connected to the signal generator, in
the periphery of the antenna b of the URX-P2 as
shown in the illustration.
11. Confirm that the decimal digit indicator that is located
in between the first digit and the second digit from the
right-most end of the LCD indicator lights on.
12. Perform the procedures 6 to 9 above.
Signal
generator
Antenna
Appro
x.100mm
URX-P2