2CT-1/CT-2 Current Transformer
Description
The CT-1 (1 GHz) and CT-2 (200 MHz) are current probes designed for either
permanent or temporary installation in the device-under-test (DUT). These
probes are particularly useful for measuring high-frequency currents in solid state
circuitry with minimum circuit loading. Due to bidirectional compatibility, the
CT-1 and CT-2 can be used to inject a signal or as an interstage transformer.
The probes inductively measure current through a conductor and develop a
voltage proportional to the current. For each mA of input current, they output
5 mv (1 mv for CT-2) of signal when properly terminated. Since the CT-1 and
the CT-2 are dynamic current probes (non-DC), the presence of DC current
affects their performance. Figures 2 and 3 show the influence of DC current on
frequency response.
Frequency (Hz)
100%
90%
80%
70%
1 G10 M100 k 100 M1 M10 k
0.5 ADC
0 ADC 1 ADC
This response was obtained with the + side of the CT-1 facing
the signal source (preferred connection above 800 MHz)
Figure 2: CT-1 frequency response vs. DC current