Tektronix 1730 Series, Instruction Manual

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1730–Series Checks and Adjustments
5–34
f. ADJUST – R856 (RGB Offset) to center the display at mid screen.
11. Adjust RGB Compensation
a. Remove the color bar signal from the CH–A INPUT.
b. Input a 10 V, 2 kHz square-wave signal, from the function generator, to
pin 1 (with pin 2 still grounded) of the 1730-Series rear-panel REMOTE
connector.
c. Connect a probe from the test oscilloscope to the junction of R854 and
R755. See Fig. 5-7 for locations.
d. ADJUST – C953 (RGB Comp) for best transient response.
e. Remove the connections from the REMOTE connector.
12. Adjust Output Bias
a. Set the VERTICAL Position control fully clockwise.
b. Connect the voltmeter lead to the collector (transistor case) of Q280.
See Fig. 5-7.
c. ADJUST – R489 (Limit Cent) for +0.8 V.
d. Set the VERTICAL Position control fully counterclockwise.
e. Connect the voltmeter lead to the collector (transistor case) of Q289.
See Fig. 5-7.
f. CHECK – that the voltage is +0.8 V. If it is not, repeat parts a. through
f. until the collector voltages are balanced at the same dc level.
13. Adjust Calibration Signal Amplitude
a. Connect the VAC signal to the 1730-Series CH–A INPUT; do not
terminate. See Fig. 5-10.