Vintage Geiger Counter

The Model F-6 was introduced in 1955. It was a portable Geiger counter with an external probe. It had a large meter and built-in loudspeaker for aural indications. The probe detects both beta and gamma. Probe detects beta without the usual window opening and thus is dust free and easy to decontaminate. It was sensitive from 500-5,000 cpm. It weighted 7.5 lbs. It operates on 900 volts. It has a 5’ self-coiling cord for greater reach. It sold for $159.50. "Geiger Counter F-6" was manufactured by Technical Associates in Burbank, California. Built in a one-piece drawn steel case, it has more weather stripping than some other civilian models of its day, but couldn't be considered weatherproof. For batteries, it requires 2 "B" batteries, Eveready No. 467 (NEDA 200), 67 1/2 volts each, plus 4 "D" cells. Note that a "B" battery is not a particular size, just a schematic designation when talking about any high-voltage battery in a vacuum tube circuit. Besides the Geiger tube, this unit uses 4 tubes, 2 ea. 1U4, a 5823, and a 6174. It is operational, except for its Geiger tube (see the Show 'n Tell section). The probe on the TA is a plastic/phenolic to accept beta radiation in addition to gamma. This is the only unit I own with an external speaker. Not sure, but it may have been the model they used in a couple of episodes of the original "Superman" tv series. It certainly "looks" like a Geiger Counter. This antique is absolutely amazing.