661 Series plug-in interface

The Tektronix 661 oscilloscope mainframe takes two plug-ins: the sampling plug-in (e.g., 4S1) and the timing plug-in (e.g., 5T1).

Overview

The sampling plug-in interfaces with the Type 661 mainframe via two multi-pin connectors:

• P1 Power Connector
• P2 Readout Connector

The timing plug-in interfaces with the Type 661 mainframe via two multi-pin connectors:

• P3 Digital Readout Connector
• P4 Interconnecting Plug

There is also a pair of coaxial cables terminating in Gremar connectors connecting the sampling plug-in to the timing plug-in. The coaxial cables are part of the mainframe, but are not electrically connected to the mainframe. They just pass through.

Sampling Plug-in Interface

P1 Power Connector

Pin Function Comment 1 unused 2 unused 3 −19 V 4 −25 V 5 −100 V 6 Staircase In 7 Ground 8 B Out To Horiz 9 Ground 10 B Vert Out 11 A Vert Out 12 Ground 13  unused 14  unused 15 +300 V 16 unused 17 +100 V 18 +19 V 19 Staircase Out 20 ground 21 blanking 22 ground 23 ground 24 Vert Sig Out Pin group function legend  DC power   AC and heater power   Deflection and Trigger Signals    Control Signals  Timing Plug-in Interface