Tektronix 1780-R - page 121

Measurements

1780R-Series Operator’s Manual 4–9

Table 4–2: DIFF GAIN Front-Panel Configuration

VECTORSCOPE Vector display enabled, other choices locked out.

WAVEFORM Demodulated sweep displayed, all front-panel choices

locked out. (There is no LED to indicate demodulated

sweep.)

INPUT Status does not change. All differential modes locked out; if

a differential mode was enabled, input is forced to CH A.

REFERENCE Status does not change.

FILTER Locked out.

WFM SWEEPS Set to One Line when DIFF GAIN is selected. If <SINGLE>

mode is selected, any of the other sweeps can be selected,

using front-panel controls. If <DOUBLE> is selected, the

instrument is set to One Line. The Field, Two Line, and

Three Line Sweeps are locked out.

GAINS Vectorscope and Waveform gains can be adjusted while in

DIFF GAIN mode; the new settings will be saved when the

Measurement menu is exited, and reinstated when DIFF

GAIN mode is again enabled.

WAVEFORM POSITION The Horizontal and Vertical Position controls can be

adjusted while in DIFF GAIN mode; the new settings will be

saved when the Measurement menu is exited, and

reinstated when DIFF GAIN mode is again enabled. The

Vertical Position Control range is limited in order to keep the

signal on screen.

VOLTAGE & TIMING

CURSORS Not available in DIFF GAIN mode.

Noise reduction can be used in both <SINGLE> and <DOUBLE>

modes.

NOTE. Freeze available only with Noise Reduction ON.

Freeze. To capture the display (right CRT only), touch <NOISE

REDUCTION ON>, then touch <FREEZE>.