Tektronix 1740A/1750A Making Vector Measurements, Chroma Bandwidth, Differential Phase and Gain, Basic Measurements, Figure 4-5.Differential Gain and Phase Measurements

Basic Measurements

Making Vector Measurements

Chroma Bandwidth

The horizontal and vertical axes of the vector graticule contain markings for checking chroma bandwidth. A subcar- rier frequency sine wave (whose amplitude places it on the outer compass rose) is used as a reference. When the frequency is changed, the diameter of the circle should reduce. At a point equal to 70% of full amplitude (-3 dB), there are gaps in the horizontal and vertical axes. This calibration aid makes it possible to check the -3 dB points of the demodulator output amplifiers.

Differential Phase and Gain

Differential gain (dG) and differential phase (d∅) measurements use the graticule markings located at the outer edge of the B-Y or U axis. See Figure 4-5.

10o dφ

2°dφ

Figure 4-5. Differential Gain and Phase Measurements.

1740A/1750A Series Waveform/Vector Monitor User Manual 4-9

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