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7.11.2.
Realigt`ment o£
234 T3:
Control settings:
SUPPLY switch:
STAIID BY
MODE switch:
Al
lo Insert extender board.
2c Connect frequency counter between temi.nals 234-32c and 234-4c
(ground) D
3o I)epress inorse key or altemacively short circuit the tertBinals of
the jack sc)cket 3C)O SK2.
4o Adjust 234 T3 until counter reads 1500 Hz ± 1 Hz.
.12.
A
Reali
nment o£ Loo
Translator
Measuring Equiptnent :
Signal Generator covering the range loo kHz to 10 mz.
Oscilloscope or RF Voltneter having an input impedance greater than
10 koha and a sensitivity of at least 10 nv/div.
Extension board
4b
7.12ol
Realigrment and Ctieck of 1.5 mz LP-filter:
Control settings:
SUPPLY suitch: STANI) BY
::e:::n:: ::::ctffb c:::tziha:I:a:::ir sockets.
2. Adjust the cores of L2, L3, L4 and L5 until they are flush vi.th the
top of the coil former.
3a Comect the signal generator to pin 12 of 208 IC4 through a 0.1 pF
capacitor and comon.
4. Connect the c>scilloscope prcibe tip to the collector o£ 208 TR5 and
the oscilloscope ground clip to comon.
5. Adjust the sigrial generator to 20nv ms.
6D Sweep the Signal generator from 60 kHz to 1.45 mz; the voltage
reading level on the oscilloscope must not change core than 1 dBo
(Take care that the output level of the signal generatclr does
not change during the sveep).
7. Readjust the signal generator until the signal level measured is
decreased by 3 dB relative to the mxitnun signal level found under
5)c The frequency should then tie betveen 1.5 rmz and I.9 rmz.
8c Readjust the Signal generator until the signal level measured is
decreased by 20 dB relative to the naxi"n signal £ciund under 5) .
The frequency should then tie betveen 1.8 mz and 1.9 rmz.
7,,12a2D
Realignment of TI.ansformer 208 T1:
Control settings:
StJPPLY switch: STANI) BY
.I/i)\
I.
Insert the PCB
into its socket.
2. Select t>y means of the keyboard 29,goo.0 rmz as the [E.ansnittins
i requency .
7-6
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