Early
Digital Test
Equipment 		Northeastern 40-80
Counter		  

Manufacturer: Northeastern
Model: 40-80
Year: 1964
Schematic: RE
 
Max. Rate: 30 MHz (measured)
Display: NIXIE
Digits: 8
Logic: discrete transistor Ge-PNP

Rugged well-built unit, sealed circuit boards. The unit in the photo includes a 200 MHz pre-scaler plug-in (right side).


Clockwise from top left: an input amplifier, dual decoder/NIXIE driver, a low speed decade counter with latch, and a high speed decade counter with latch for the first digit.


- Unit Log -

Serial Number: 26252
Year of Manufacture: 1964 (Component date stamps)
Other Identification: Canadian Armed Services
Navy CD176519
6625-21-799-5779
Frequency Meter
Serial No. 26252
Date of Receipt: 1995 Nov
State upon Receipt: Good physical condition. Dusty. Functional.

Date: 1995 Nov
Procedure: Line cord replaced.

Date: 1995 Nov
Procedure: Two NIXIEs do not light light up. Bad ones moved to digits 10^6 and 10^7.

Date: 2005 Jul 26
Procedure: Bad NIXIES replaced with B-5092 (8421) (originals are B-5031). Replacements placed in digits 10^5 and 10^6, both have a problem illuminating on upper right of numeral '8'. One original NIXIE which has only partial illumination on some numerals placed in digit 10^7.

Date: 2005 Jul 26
Procedure: Some dusting done, could do with more.


  .. | Northeastern 40-80 | ..
Early Digital Test Equipment 		bhilpert