Phantastron

The Phantastron is a self-gating linear sawtooth generator circuit based on a pentode/triode Miller integrator.

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It is used in the 162, 512 and possibly other instruments.

See description on page 26 of this document:

• John Mulvey, Some Basic Vacuum Tube Circuits used in Tektronix Instruments (Third Revision 1964) / (1960 edition)