Tektronix 070-8462-03, Instruction Manual

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Corrective Maintenance
7–18
1735 HD High Definition Waveform Monitor
1. Unsolder the wires (Tektronix part number 196–3146–00) from the
following 12 locations on the BNC board: P605, P607, P609, P615, P619,
P625, P629, P635, P639, P645, P647, and P649.
2. If the Main board is to be replaced, remove the wires and install them on the
replacement board. Insulated 18 gauge wire straps may also be used.
3. Unplug all four CRT deflection plate leads (red, green, brown, and blue)
from the CRT.
4. Unplug J4 on the Main board and J5 (Low Voltage Power) on the Power
Supply board.
5. Remove the following knobs: FOCUS, SCALE, and INTENS.
6. Remove the eight screws (shown in Figure 7–8) that hold the Main board in
place.
7. Carefully unplug the Main board from the two connectors on the Control
board.
8. After the Main board has been pulled outward sufficiently to clear the
Control board connectors and the rear panel, slide the Main board toward the
rear of the instrument until the control shafts have cleared the front frame.
Lift the board out.
9. When reinstalling the Main board, refer to Figure 7–5 for correct positioning
of CRT deflection leads.
Figure 7–8: Screws that hold the Main board (A3) in place
Removing the Main Board