Model NS-LB Noise Generator

© Brooke Clarke, N6GCE 2002 - 2011

A.R.I. NS-LB Noise Gen


This Noise Model NS-LB generator was made by Aerospace Research, Inc. of Boston, MA.  It uses a 5722 Noise diode tube with a Tungsten filament using the "shot effect".  There is a solid state control circuit that varies both the DC filament current and the plate voltage in order to produce a variable excess noise.

The filament voltage needs to be varied from 2.0 to 5.5 Volts while the plate voltage varies from 10 to 200 Volts.  The tube is speced up to about 500 MHz, but the construction of this noise generator may go higher. 
NF (Noise Factor) = 20 * I * R
NFdb = 10 * LOG10 (20 * I * R)

where: I = Plate current in Amps, R = generator resistnace, 50 Ohms in this case.

Type-N male output.


Manual or schematic Noise Genertor Manual Info

HP 343A VHF Noise Source

I think the HP VHF source uses the same 5722 noise tube.  It's specified as 5.2 dB Excess Noise Ratio (ENR) and 3.1 ma.
Maybe 3.3 ma would be closer to 5.2 dB ENR.


Radio Museum - 5722 Tube

Sylvania Technical Manual 1949
- 5722_gif1 - 5722-gif2  -  5722_gif3

Back to Brooke's Products for Sale, Military Information, Home page

This is the  time this page has been accessed since since 13 June 2002.