[time-nuts] HP 5071A Electron Multiplier of Cesium Beam Tube

[Mike Monett]

  [...]

  > Peak beam current with this tube is about 25 nA (-980mv pk into 40
  > Mohms), compared  to the 80-200 nA typical range  that  the manual
  > calls for, and the Cs resonance valley isn't much higher  than the
  > noise floor observed with no RF applied (-550 mv versus -520 mv).

  > But the  output phase noise, at least, is well  within  specs (-88
  > dBc/Hz at  1 Hz in short time constant mode, spec=-82  dBc/Hz, and
  > 105 in LTC mode, which is actually better than the -96 dBc/Hz spec
  > for the option-004 tube.)

  [...]

  > john, KE5FX

  John, out  of  curiosity, are you using  homebrew  or  commercial to
  measure the phase noise ?

  If it's homebrew, is there any other information available?

  Thanks,

  Mike