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Tektronix 7B80
400 MHz timebase
Tektronix 7B80 Timebase plug-in with Option 2

Compatible with 7000-series scopes

Produced from 1976 to 1990

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

The Tektronix 7B80 is a 400 MHz single time base plug-in without delay function for 7000-series scopes, typically the 7800 Series, e.g. 7844. It uses the 155-0126-00 trigger amplifier followed by the 155-0109-01 trigger detector.

Option 2 adds support for X-Y mode via a "Display mode" switch (pictured). When X-Y mode is selected, the X-axis signal is taken from the internal trigger path, irrespective of Trigger Source, Magnification (×10), variable sweep speed, and X position controls.

The companion delaying timebase for use in 4-slot mainframes is the 7B85. The 7B50A is essentially a 7B80 with its fastest calibrated sweep rate limited to 5 ns/div.

From Tekscope Vol.8 No.1, 1976:

Les Larson developed the trigger circuitry and served as Project Manager for the 7B80 and 7B85. The sweeps were designed by Bruce Hofer and the DVM and related logic by Paul Farley. Much credit is due Art Metz for his work on the trigger input 1C which includes the peak-to-peak automatic trigger circuitry. Gene Andrews, Program Manager, provided overall direction for the project.

Key Specifications

Sweep 10 ns/Div to 5 s/Div (1–2–5), ×10 magnifier (down to 1 ns/Div), variable sweep (up to ×2.5) and holdoff (up to ×2 sweep lengths at 20 ms/Div and faster)
Excluded sweep First 10 ns in 78xx, 79xx; First 20 ns in 77xx; First 50 ns in other mainframes
Trigger 50 mV or 0.3 Div up to 50 MHz, 250 mV or 1.5 Div up to 400 MHz; AC >30 Hz, LF REJ >30 kHz, HF REJ <50 kHz
Jitter <100 ps at 400 MHz
Ext. Trigger Max. 250 V DC+peak AC, 1 MΩ // 20 pF
Sweep/Trigger Modes Peak-Peak Auto, Auto, Norm, Single Sweep


Documents Referencing 7B80

Document Class Title Authors Year Links
Tekscope 1976 V8 N1.pdf Article Delta Time Measurement for the 7000 Series Paul Farley Les Larson Bruce Hofer 1976
Technology report oct 1979.pdf Article Patent Received: 4,109,182 Simultaneous Delayed Sweep Display Oliver Dalton 1979


Year 1977 1980 1984 1987 1990
Catalog Price $745 $1,000 $1,485 $1,660 $2,080
In 2023 Dollars $3,800 $3,700 $4,400 $4,500 $4,900



The 7B80MODWJ is a 7B80 timebase having various controls removed:


Some Parts Used in the 7B80

Part Part Number(s) Class Description Used in
155-0049-00 155-0049-00 155-0049-01 155-0049-02 Monolithic integrated circuit sweep control with lockout 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
155-0109-00 155-0109-00 155-0109-01 Monolithic integrated circuit trigger 5B25N 5B31 5B40 5B42 5B44 5S14N 7B50A 7B53A 7B80 7B85 7B87 7B81P 7B90P 7S14 7612D SC502 SC503 SC504
155-0126-00 155-0126-00 Monolithic integrated circuit trigger source selector and P-P auto amplifier 7B50A 7B80 7B85 7B87 7B81P 7B90P
2N5454 151-1042-00 Discrete component dual n-channel JFET 7B80 7B53A 2213 2215 2235 T912 T921 T922 T932 T935