6AK7/6AG7

6AK7 was an improved variant of industry standard 6AG7 intended for applications in radar receivers as video amplifier. Increased transconductance and anode current raised to 20 mA, compared to its 6AG7 prototype. Bare metal ring over the base, in order to ground the metal skirt when inserted in a special socket with side fingers.

US RMA registration to Canadian REL during the war, in January 1944. Being very similar to its prototype, REL requested the double marking permission, 6AK7 / 6AG7 for this tube, as specified in the RMA record No. 363. No info about any US productions with 6AK7 single marking. Known samples by Canadian Westinghouse show the dual marking.

Low-loss micanol base.