1142-A

The General Radio 1142-A Frequency Meter and Discriminator was introduced in Catalog Q (1961) and remained available through Catalog T (1968).

The 1142-A is an analog, direct-reading frequency meter with the addition of an interpolation feature. With the interpolation control set to Direct, the frequency can be read directly from the panel meter with ±1% accuracy. To obtain better resolution and accuracy, engage the interpolation setting (see manual). The 1142-A has three outputs for connecting chart recorders (Direct, Interpolation, and FM).

Specifications

• Frequency: 3 Hz to 1.5 MHz in 5 decade ranges
• Maximum Voltage: 300 V_p-p up to 150 kHz, 70 V_p-p above 150 kHz
• Sensitivity: RMS 20 mV, 20 Hz to 150 kHz; rising to 200 mV at 3 Hz and 1.5 MHz. Up to 5 V for narrow pulses (1 ns).
• Impedance: 100 kΩ dropping to minimum of 5 kΩ above 500 kHz
• Accuracy: 0.2% of full scale for all but the extremes of frequency coverage

Links

• Experimenter describing 1142-A February 1961

Photos

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