1213-D

The General Radio 1213-D Unit Time/Frequency Calibrator was introduced in 1961 Catalog Q and remained available through Catalog R 1963.

The Type 1213-D is two part device, the first part is crystal controled oscillator that produces four calibration signals that are rich in harmonics. The signals are generated by a 5 MHz crystal oscillator which is then doubled followed by three stages of dividers to produce one of four marker outputs. The selected output is the fed into a harmonic generator where its available at the front panel when switched to "Timing Markers" position. The second part of the 1213-D is a built in mixer-amplifier that when switched to the "Audio Beat Signal" the front jack becomes an input. This input when mixed with the internal selected marker signal create a beat note at the audio binding post output. Using this output to observe a zero beat with headphones or Lissajous figures and an oscilloscope the input signal is calibrated. As a unit oscillator it requires an external power supply, the type 1203-B is recommended.

Specifications

• Frequencies: 10 MHz, 1 MHz, 100 kHz, 10 kHz.
• Frequency Adjustment: ±5 ppm.
• Amplitude: 10 Mc 5 V peak-to-peak; 30 V peak-to-peak at lower output frequencies from pulse amplifier.
• RF Harmonics: usable to 1000 MHz from 10 MHz output, to 500 MHz from 1 MHz output, to 100 Mc from 100 kHz output, and to 10 Mc from 10 kHz output.

Links

• Experimenter describing Type 1213-D Unit Time Frequency Calibrator October 1959

Photos

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