Tektronix 1780-R - page 101

Operating Instructions

1780R-Series Operator’s Manual 3–49

For 1781R (PAL), touch <GAIN CAL> and use the large

knob to make the circle match the compass rose.

b. Touch <CAL OSC> until <OFF> is outlined.

6. To check the Vectorscope Gain adjustment, push the front-panel

CALIBRATE button to enter the Calibration menu, then push the

button under the left CRT.

a. Apply a color bar signal (with 7.5% Setup for NTSC) to a

1780R-Series input channel and select that channel for

display. A 100% or 75% color bar signal can be used,

depending on the vectorscope readout (derived from the

Configure menu setting).

b. Push the front-panel PHASE button and adjust the large

knob to properly align the phase of the burst and vectors

on the graticule. Push the PHASE button again to exit this

mode.

c. For 1780R (NTSC): Touch <GAIN 1 CAL>. Check that

the color bar vectors are in the graticule boxes. Set the

generator to 0% Setup, touch <GAIN 2 CAL (NO

SETUP)> and check that the color bar vectors are in the

graticule boxes. Return the generator to 7.5% Setup if

desired.

For 1781R (PAL): Touch <GAIN CAL>. Check that the

color bar vectors are in the graticule boxes.

d. Exit Calibrate menu.

Vectorscope Calibration Procedure

(for Software Versions 1.10 & Below)

Perform Steps 1 through 6 for both 1780R and 1781R (NTSC and

PAL).

1. Push the front-panel CALIBRATE button to enter the Calibration

menu. If Password operation is enabled, enter the password now.

Waveform calibration will be displayed.

2. Push the button under the left CRT (LED will light) to select

Vectorscope calibration, shown in Figure 3–23.