Standing Wave Indicator 415A

The 415A Standing Wave Indicator is designed for use with the 805A Slotted Line. It may also be used as a null indicator, or for bridge measurement, and provides a 75000 ohm input cirquit for this application.
The 415A consists of a high gain amplifier with very low noise level, operating at fixed audio frequency. Amplifier output is measurement with a Square-Law calibrated vacuum tube voltmeter. This meter reads direct in VSWR and in db.

Frequency: Normally 1,000 cps ±2%.  Plug-in units for other frequencies, 300 to 2,000 cps are available. Request unit 4119-42, and specify frequency. Amplifier “Q” is 20  ±5.

Sensitivity: 0.3 µv. gives full scale deflection. Equivalent noise level referred to input is 0.04 µv.

Calibration: For use with Square-Law detector. 60 db level covered in 6 ranges.  Accuracy ± 0.1 db per 10 db step.

Gain Control: Adjusts meter to convenient level. Range is approx. 30 db.

Input:  Connects to crystal rectifier or bolometer. Bias of 8 v. ±0.5 v delivers approx. 8.75 ma. to a 200 ohm bolometer or 1/100 ampere instrument fuse. 75,000 ohms for null measurement. One terminal at ground.

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Elenco delle radio e altri apparecchi della Hewlett-Packard, (HP); Palo Alto, CA