Checking And Adjusting; General Information; Right-Hand View - Philips Pm 3342 Manual

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Checking and adjusting
A. GENERAL INFORMATION
The tolerances mentioned are factory tolerances; they
apply when the apparatus is readjusted completely.
They may differ from the data given in II.
A summary of the adjusting elements, their nomencla-
ture and location has been given in V.
With the aid of these data, it is possible to carry out all
the adjustments of the dual trace unit PM 3342 and to
check the proper working of the plug-in unit.
For this, the unit should be inserted into the Y-plug-in
compartment of a correctly adjusted basic oscilloscope
PM 3330.
Some of the adjusting elements are on the right-hand
side of the unit and are not directly accessible. When
these elements must be adjusted, the unit should be
connected to the basic oscilloscope via the rigid exten-
sion plug (code number 4822 263 70009).
For a complete adjustment of the instrument the se-
quence as described in this chapter is to be preferred.
R 313
Fig. 6. Right-hand view
B. D.C. BALANCE
This adjustment should be carried out when the unit
has obtained its operating temperature, i.e. approxi-
mately 15 minutes after switching-on. Set the knobs
of the basic oscilloscope to the following positions:
"TRIGG. MODE": "AUT."
"TRIGG. SOURCE": "[NT."
"TIME/cm": "2 msec./cm"
"X-DEFLECTION": "TIME BASE A"
1. Channel A
R213 (Fig. 6)
Set "MODE" (SKS) to "A" and turn "D.C. BAL."
(R2) to its mid-position.
During this adjustment, keep the time-base line on
the screen with "SHIFT" (R1).
— Adjust the coarse control "D.C. BAL." (R213) so,
that the time-base line hardly moves when "V/cm"
(R3) is turned fully clockwise or anti-clockwise.
— With the fine control "D.C. BAL." (R2), adjust for a
stationary display.
I
R 213
TS 608
TS 609
TS 602
TS 603
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