Tektronix 1730 Series, Instruction Manual

Page: 130 / 258

1730–Series Checks and Adjustments
5–14
m. Adjust the multiburst Frequency for a 5 MHz sine wave as measured on
the digital counter.
n. Select the 1730–Series INT REF and 1 LINE SWEEP. Turn on the
MAG and VAR GAIN. Adjust the VAR GAIN control for approximately
six vertical divisions of display.
o. Set the multiburst generator to Composite.
p. Use the 1730–Series HORIZONTAL Position control to display all but
the first and last 10% of the sweep.
q. CHECK – for 10 cycles over 10 graticule divisions,
±
1.5 minor
divisions.
r. Switch the multiburst generator to Continuous and check that its
frequency, as measured on the digital counter, remains set at 5 MHz.
Return to Composite.
s. Repeat parts q and r of this step several times to ensure an accurate
check.
7. RGB/YRGB Parade Display
REQUIREMENT – Attenuated sweep: 3.4 to 4.1 div. for 3–step or 2.5 to
3.1 div for 4–step. Staircase input gain: 10 V = 9 horizontal divisions
±
1.4 div.
Attenuated sweep responds to sweep rate and magnification controls.
a. Connect the color bar signal to the CH–A INPUT. Terminate the open
side of the loop–through with a 75
W
end–line terminator.
b. Display the color bar in 1LINE. Center the display. Note the position of
the plug on J456 on Assembly A3 that selects the 3– or 4–step Parade
display. The 2–3 position selects attenuation for a 3–step display.
c. Connect the Parade Display Test Connector to the REMOTE connector.
See Fig. 5-1.
d. CHECK – that the sweep has shortened to 3.4 to 4.1 divisions if P456 is
set to a 3–step display, or 2.5 to 3.1 divisions if the plug on J456 (1–2) is
set for a 4–step display.
e. CHECK – that the shortened sweep is 1LINE or 2FLD, according to the
SWEEP controls, and that the sweep can be magnified.
f. CHECK – that the display can be moved to the sides of the screen with
the HORIZONTAL Position control. It may be necessary to adjust
R856.
g. Position the display to the right side of the screen; it may be necessary to
adjust R856, RGB Offset, to increase range of positioning. Fig. 5-7