1390-B: Difference between revisions

Revision as of 21:14, 21 February 2024

The General Radio 1390-B is a random noise generator introduced in 1961. It first appears in Catalog Q and remained available through Catalog GR1978. The Type 1390-B provides random noise on three ranges from 20 kHz to 5 MHz. It produces electrical noise using a 6D4 gas-discharge tube, V2, operated in the field of a permanent magnet. The noisy plate voltage of the 6D4 tube drives two stages of amplification. Between the amplifier stages, filter networks shape the three bands. A voltmeter displays RMS voltage then of the noise signal before it is fed to a five position decade attenuator at the output.

Specifications

Frequency Range: 5 Hz to 5 MHz in three bands.
Output Voltage: 3 V for 20 kHz range, 2 V for 500 kHz range, and 1 V for 5 MHz range.
Output Impedance: 900 Ω
Output Attenuator: 1, .1, .01, .001, and .0001 times the RMS Voltmeter reading.

Manuals

General Radio 1390-B Random Noise Generator Manual 1390-0100-K (1965)

Links

Photos

Noise tube, V2, operating in magnetic field

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 [[File:GR 1390-B Front.jpg|thumb|450px|right|General Radio 1390-B Random Noise Generator]]
-The '''General Radio 1390 Random Noise Generator''' was [[introduced in 1961]].
+The '''General Radio 1390-B''' is a random noise generator [[introduced in 1961]].
 It first appears in [[Media:GRwiki Catalog Q OCR 1961.pdf|Catalog Q]] and remained available through Catalog GR1978.
 The Type 1390-B provides random noise on three ranges from 20 kHz to 5 MHz.