Maintenance-2225 Service
Power Transformer
AttenuatorITimebase Circuit Board
The Power Transformer (T901) can be removed and
reinstalled as follows:
1. Disconnect connector J902 from the Line Filter
board. (The J902 connector is not polarized so
can be fitted either way). Note the orientation of
the connector for proper reinstallation.
2. Note the physical orientation of the Power Trans-
former. Undo the two locking nuts from the
center of the Power Transformer.
3. Supporting the Transformer, withdraw the center
bolt (complete with the rear stiffening plate).
To reinstall the Power Transformer, perform the
reverse of the preceding steps.
Mains lnput Circuit Board
The Mains lnput circuit board can be removed and
reinstalled as follows:
1. Disconnect connector J902 from
the Mains lnput
board. (The J902 connector is not polarized so
can be fitted either way. Note the orientation for
correct reinstallation.)
2. Unsolder W903 from Mains lnput board.
3.
Disengage the Power switch extension shaft
from the Mains Power switch
(S901).
4.
Remove the two screws and nuts that secure the
AC Power inlet connector to the rear chassis.
5.
Remove the grounding screw and nut that se-
cures the Mains lnput board to the inner chassis.
L
WARNING
1
The screw and nut which secure the Mains
lnput circuit board to the chassis provide safe-
ty grounding and must be properly replaced
when reinstalling the Mains lnput circuit board
6.
Pull the Mains lnput board towards the inner
chassis and up out of the instrument.
To reinstall the Mains lnput board, perform the
reverse of the preceding steps.
The
AttenuatorITimebase circuit board can be
removed and reinstalled as follows:
1. Turn the instrument over (Main circuit board up)
and unsolder the two
resiStors from the CH 1 and
CH 2 attenuator switches. Also unsolder the
grounding straps connected between the Front
Panel and the
AttenuatorITimebase boards,
noting their respective positions. Turn the instru-
ment over again and continue with the
Attenua-
tor1Timebase circuit board procedure.
2. Use a 1116-inch hex wrench to loosen the set
screws on both the CH 1 and CH 2
VOLTSlDlV
Variable knobs, and SECIDIV Variable knob.
Remove the knobs. Withdraw the CH
1
and CH 2
VOLTSIDIV knobs and SECIDIV knob.
3. Remove the two rear screws that secure the
AttenuatorlTimebase board to the support
pillars.
4.
Remove the screw that secures the Front Panel
brace to the AttenuatorITimebase board. Turn
the instrument over (Main circuit board up) and
remove the screw that secures the Front Panel
brace pillar to the AttenuatorITimebase board.
5.
Remove the Focus knob shaft by disengaging it
from the Focus pot and pulling the shaft out
through the front panel.
6.
Disconnect the following cables from the Attenu-
I
atorlTimebase circuit board, noting their
locations for reinstallation reference:
a.
J90, a six-wire cable located at the rear
edge of the board.
b.
J755, a four-wire cable located at the rear
right-hand corner of the board.
c. J30, a four-wire cable located to the left of
the CH 1 attenuator switch.
d. J80,
a
four-wire cable located between the
CH
1
and CH 2 attenuator switches.
I
e. J7, a six-wire cable located between the
CH
2 attenuator switch and the SECIDIV
switch.
f.
J701, a six-wire cable located at the front
right-hand corner of the board.
REV
APR
1990
6-1
5
Scans
by
ARTEK
MEDL4
=>
To Next Page
Loading...