Heintz & Kaufman Ltd.; South San Francisco: Producer of transmitting tubes etc. during the 30ies and 40ies. It is not "Heintz & Kaufmann" as often seen (with couble n) but Heintz & Kaufman - see lables on tubes.

Heintz & Kaufman introduced a line of transmitting tubes using a tantalum grid welded frame and tantalum anode. These tubes, identified by the trade mark Gammatron, did not require getters and could well withstand severe overloads, withouth developing gas inside the bulb. Later the trade mark Gammatron was printed also on the boxes of other conventional tubes. JAN military code was CHK.

History: Heintz & Kaufman Ltd.; South San Francisco: Logo HK in a circle, Brand "Gammatron". An example is the "Gammatron 24-G", made e.g. in 1944.

Bill Eitel, W6UF and Jack McCullough, W6CHE worked for Heintz & Kaufman in the early thirties. They were developing the HK 354 which was designed to compete and surpass the RCA 852 tube, which along with the 204A tube, were the biggest high power amateur types at that time. H & K didn't express too much interest in marketing the 354 and shortly after that time Bill and Jack left Heintz & Kaufman to set up their own tube making operation.