Vintage Monsanto Electronic Instruments Model 103A counter-timer with a five-digit Nixie display. The unit powers up and all five Nixie tubes light. It carries an original property sticker reading “PROPERTY OF A.E.C. / SANDIA CORP.” and is marked serial number 868-A-730.

The Atomic Energy Commission was the federal agency that ran the U.S. nuclear program until it was abolished in 1975. Sandia Corporation operated Sandia Laboratory in Albuquerque for the AEC — the engineering lab responsible for the non-nuclear parts of the nuclear weapons stockpile, later Sandia National Laboratories. This is ordinary bench instrumentation that left that system with its property mark still on the panel, not a specialized nuclear instrument. The sticker is worn but legible.

Monsanto sold the 103A around 1969–1971 as a 20 MHz counter-timer in its small lab line. Period ads list it at $420. Front-panel controls include Power, Reset, Display, Gate, Sensitivity, and Input A, plus a function switch covering frequency, time interval, manual gate, and related settings. An Over Range lamp sits beside the display window. Case and panel show honest shop wear: scuffs, rubbed lettering, and the usual marks of a used instrument. No cables, probes, or manual are included.

Condition notes

• Powers on; all five Nixie tubes illuminate

• Superficial cosmetic wear consistent with lab use

• Sold as a working vintage instrument, not as calibrated test equipment

• Line-frequency timebase on this model; do not expect crystal-counter accuracy

Packed for a heavy metal instrument. Ask questions before buying.

Brand	Monsanto
MPN	103-A
Country of Origin	United States

Monsanto 103-A Counter Timer Five Nixie Tubes ACE-Sandia Sticker-Working

Specifications