ML659 V2 Radiosondes have an internal aneroid barometer, humidity sensor, and thermometer. When attached to a balloon and released, they give a continuous report of weather conditions versus altitude.

There are three internal circuit boards, one for the sensors, one to transmit at 403 MHz (easily adapted to the 420 MHz ham band), and one for the VLF Omega navigation system.

Federal Stock Number 6660-01-166-8048. Unused and still sealed in their original packages. Sealed water activated battery has a very long shelf life.

We offer these primarily as an unusual militarty collectible.

Approximate shipping weight: 5 pounds.
Available in quantity.