BRIEF DESCRIPTION OF MODEL 667 SOLID STATE TUBE TESTER The B&K Model 667 is a versatile, up-to-date, completely solid state, portable tube tester that will test all tubes commonly used in today’s electronic industry, including many foreign tube types. The following tests are made on each tube: 1.) Shorts and leakage between any element and all other elements, with a sensitivity of I megohm. Because of exclusive “multiple lockout switch” all modern tubes which have more than one pin connected to the same element can still be completely tested for shorts from each element to every other element. 2.) Quality is checked in a test circuit that determines the full capability of cathode emission under current loads and voltages simulating actual operating conditions. 3.) Grid emission, gas, grid contamination, or obscure grid to cathode leakage are all disclosed by an exceptionally sensitive grid current check. This test will indicate with less than 1 microampere of grid current. 'I'llis tester incorporates the easy-to-use lockout pushbuttons to increase testing capability and prevent obsolescence and a special tube chart display holder to facilitate rapid, error-free testing. The tester is housed in a highly attractive, weatherproof, very durable, VIP/Attache-type carrying case.