Sony SPP-A2770 - 2.4ghz Cordless Telephone, Руководство по обслуживанию

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SPP-A2770
RF TESTING
This test is for checking the RF system without disassembling the
set in servicing. Perform measurement using the spectrum ana-
lyzer and jig antenna.
Note:
To perform the RF testing, prepare the panel (BASE CABINET
(UPPER) ASSY) for SPP-A2780, and use it connecting the panel for
SPP-A2780. (Refer to page 4)
RF Testing method:
Please follow the below instruction to perform RF test.
For the detail of test mode, Refer to the each items of “BASE
UNIT” section and “HANDSET” section.
1. TRANSMISSION CHECK
1-1. Setting
Connect a receiving antenna to RF INPUT of Spectrum analyzer
and set the unit 10 cm (4 inches) away from the receiving antenna.
Measuring tool : Spectrum analyzer (equivalent to HP8595E)
Jig
: Receiving antenna (for Spectrum analyzer)
1-2. Transmission Waveform Check
Purpose:
It is necessary to check spectrum wave of transmission wave which
is an important factor in order to confirm operational performance
of Spread Spectrum models. If this wave deviates from correct
wave form, normal data transmission cannot be made and, as a
result of that, possibility that occurrence of mute increases and
communication distance becomes shorter will increase.
Spectrum analyzer setting:
Center frequency: 2440.5 MHz
Span
: 10 MHz
RBW : 100 kHz
VBW : 100 kHz
Ref Level : 0 dBm
ATT : 10 dB
Jig antenna
(Utilize the antenna for handset)
Spectrum
analyzer
10 cm
Spectrum
analyzer
10 cm
Test mode setting:
– Base Unit –
1. Press three keys of
[2]
,
[6]
, and
[ERASE]
simultaneously to
enter the test mode.
2. Press the
[4]
key to activate test mode D and display “TEST
D”. (TX on)
3. Press the
[1]
or
[3]
key to change the channel to 28.
– Handset –
1. Press three keys of
[2]
,
[6]
, and
[ERASE]
simultaneously to
enter the test mode.
2. Press the
[4]
key to activate test mode D and display “TEST
D”. (TX on)
3. Press the
[6]
key to set master.
4. Press the
[1]
or
[3]
key to change the channel to 28.
Test mode setting is complete, check that the waveform on spec-
trum analyzer is displayed as below.
Measuring:
1. Maximum hold the waveform.
2. Set the maker to the peak of waveform with the Peak Search
function.
3. Measure the frequency width of points 6 dB and 20 dB lower
from the peak with the Delta Marker function. (refer to below
figure)
Specifications:
A (width of –6 dB points) : more than 1.4 MHz
B
(width of –20 dB points) : more than 1.8 MHz
REF 0.0 dBm
10dB/
CENTER 2.44050 GHz
* RBW 100 kHz * VBW 100 kHz * ATT 10dB SWP 20 ms
SPAN 10.00 MHz
A_View B_Blank Norm Norm
REF 0.0 dBm MK
∆
–510 kHz
10dB/ A_View B_Blank Norm –5.44 dB Posi
D E LTA M K R
– 5 1 0 kHz
CENTER 2.44050 GHz
* RBW 100 kHz * VBW 100 kHz * ATT 10dB SWP 20 ms
SPAN 10.00 MHz
PEAK
–6dB
–20dB
A
B
Ver 1.1