The 5718  (European: EC71) (P/N 154-0053-00) is a subminiature high-frequency triode vacuum tube.

It is used in the front end of the 321 (early models) and in the P500CF and P170CF probes.

Some instruments using part 5718

Instrument Manufacturer Class Model Description Introduced
321 Tektronix Oscilloscope 321 Portable single channel scope 1960
P170CF Tektronix Probe P170CF Cathode-Follower Probe (?)
P500CF Tektronix Probe P500CF Cathode-Follower Probe (?)
Aged/Checked/Matched Pair Details
Used in Tek Part# S/N Range
P170CF (V951) 157-0019-00 All, Note1
P500CF 157-0046-00 All, Note2
P500CF 157-0070-00 All, Note3
  • Note1:Aged/checked tubes have a green dot painted on tip
  • Note2:Aged/checked tubes have a yellow dot painted on tip
  • Note3:Aged/checked tubes have a white dot painted on tip
  • 157-0046-00 has been replaced by 157-0070-00

Reference:

Tube aging procedure / Selection and checking procedure

Links

Photos