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Tektronix 7B90P
400 MHz programmable timebase
Tektronix 7B90P front

Compatible with 7000-series scopes

Produced from 1978 to 1989

ROM Images
(All manuals in PDF format unless noted otherwise)
Manuals – Specifications – Links – Pictures

The Tektronix 7B90P is a digitally programmable 400 MHz time-base plug-in for the digitizing mainframes of the 7000 series. All controls are programmable except for the sweep calibration screwdriver adjustment and the external trigger input terminator switch. The local/remote state of the 7B90P is slaved to the local/remote state of the mainframe.

Key Specifications

Sweep 10 ns/Div to 500 ms/Div (1-2-5), ×10 magnifier (down to 500 ps/Div), no variable sweep, adjustable and programmable holdoff
Excluded sweep First 10 ns in 79XX programmable mainframes
Trigger Sensitivity
  • PP Auto Mode AC or DC: 125 mV or 0.5 Div up to 50 MHz, 375 mV or 1.5 Div up to 400 MHz
  • Norm or Single Sweep AC: 100 mV or 0.3 Div up to 50 MHz, 250 mV or 1.5 Div up to 400 MHz
Jitter <100 ps at 400 MHz
Ext. Trigger 1 MΩ: 20 pF, max. 250 V DC+peak AC; 50 Ω: max. 1 W
Sweep/Trigger Modes Peak-Peak Auto, Auto, Norm, Single Sweep


The 7B90P is controlled by a Motorola 6800 microprocessor.


Custom ICs used in the 7B90P

Page Model Part nos Description Designers Used in
155-0049-00 M079G 155-0049-00 155-0049-01 155-0049-02 sweep control with lockout Bill DeVey 335 464 465 466 475 475A 475M 485 5B31 5B40 5B52 5B42 5B44 7B53A 7B80 7B85 7B87 7B92A 7B90P 7B10 7B15 SC502 7B42N AN/USM-281C 067-0657-00
155-0109-00 M120B 155-0109-00 155-0109-01 trigger Gary Vance 5B25N 5B31 5B40 5B42 5B44 5S14N 7B50A 7B53A 7B80 7B85 7B87 7B81P 7B90P 7S14 7612D SC502 SC503 SC504
155-0126-00 M121 155-0126-00 trigger source selector and P-P auto amplifier Art Metz 7B50A 7B80 7B85 7B87 7B81P 7B90P
155-0164-00 H526(?) 155-0164-00 time slot switch 7A16P 7B90P 7A29P