FM1000 tube testing on BK 707-700

I was asked by a reader named Henry if I knew of B&K 700-707 test settings for FM1000 tube.

FM1000 is a unique Heptode detector oscillator, and as such really does not lend itself to “tube testing.”  It is best tested in-circuit.

That said, you can perform some basic checks on a FM1000 tube for shorts, leakage, and basic emission with your BK 700 or 707.  Using the bottom emission test panel, heater at 6.3v, Sensitivity at around 38, bottom switches set at 1, 8, 12, 2.

I asked Henry try testing an FM1000 tube to verify those settings, and his feedback is that they do work.


Valid XHTML Valid CSS