Overview; Description; Specifications - Keysight 537A Operating Note

Overview

Description

The Keysight 537A coaxial frequency meter is used for measuring frequency in the 0.96 to
12.4 GHz range. Accuracy is obtained from the spiral scale. The meter contains a coaxial line
coupled to a quarter- wavelength coaxial resonant cavity loaded with capacitance at the bottom of
the band. At resonance, power is absorbed by the cavity, producing a dip in the coaxial line power.
The frequency at which this dip occurs is read directly from the dial in gigahertz.
Tuning is accomplished by moving a piston. A precision lead screw, which is spring-loaded to
prevent backlash, is used to position the piston in the cavity. Due to the design of the cavity, its
electrical length is extended at lower frequencies, and there are no spurious modes.

Specifications

The instrument specifications are provided in
Table 1
Characteristic
Frequency range
Reflection coefficient off-resonance
Calibration increments
Dimensions
Height
Diameter
Weight
Dip at resonance
Dial accuracy
[a] Width (including connector): 4-5/8in (118 mm)
[b] Overall accuracy: ±0.17%, which includes allowance of ±0.02% for 0 to 100% relative humidity, ±0.0016 per ×C from 13 to 33×C and 0.03%
backlash.
Keysight 537A Operating Note
Specifications
[a]
[b]
Table 1.
Value
3.7 to 12.4 GHz
0.33 (2.0 SWR, 9.5 dB return lost)
10 MHz
5-3/4 in (146 mm)
3-1/2 in (89 mm)
3-1/2 lb (1.6 kg)
1 dB (minimum)
±0.1%
Overview
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