Navy Geiger Counter Radiac IM-74A/PDR-27C Built in 1952 by Admiral Co., this counter is almost bomb proof. This should be in working condition since it looks unused and has NOT been converted so uses 135v, 22 1/2 v and odd 1 1/2v batteries. You would have to build a power supply to make it work or you could use a bunch of 9v batteries in series (enough will fit in the case and a previous customer has done this). You can also still buy 22 1/2 volt and 67 1/2 volt batteries (need two) though the 9v was is cheaper.

These are like new, but real cold war relics. Very sensitive. Manual with circuit diagrams $7 extra (photocopy of circuit diagram free). Strap and earphones included with counter. Very sensitive 5979 end window Geiger tube detects beta and gamma on the 0-.5 and 0-5 mR scales. Internal 5980 tube detects gamma on the 50 and 500 mR scales. Bizarre meter mechanically changes scales.