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Tektronix 7844
400 MHz dual-beam non-storage mainframe

Produced from 1975 to 1988

Manuals – Specifications – Links – Pictures

The Tektronix 7844 is a 400 MHz dual-beam CRT oscilloscope that takes two 7000-series vertical plug-ins and two 7000-series horizontal plug-ins.

Versions include the 7844 bench-top lab scope and R7844 rack-mount model.

A typical configuration might have included 7A24 or 7A19 amplifiers, a 7B80 and a 7B85 timebase.


Bandwidth 400 MHz (with 7A19, 7A29) eq. 0.9 ns rise time
Fastest calibrated sweep 1 ns (with 7B80, 7B85)
Power 90-132 V or 180-264 V, 48 to 440 Hz, max. 235 W
Weight 16.3 kg (36 lbs) / R7844: 15 kg (33 lbs)


The 7844's CRT has distributed vertical deflection plates.

The power supply is a resonant switch-mode inverter with linear post-regulation, similar to the one in the 7904. Despite this, the 7844 is fairly heavy, which is mostly due to the second vertical delay line. The delay lines need extra space and are located vertically to the right of the CRT instead of below the CRT as in other 7xx4s.

Unlike other 7000 series mainframes with switch mode PSUs, the 7844 does have a fan.

The 7844 is more complex than all other 7000 mainframes because vertical and horizontal amplifiers as well as the Z axis control boards exist twice, and there is an extra switching logic board.



  Year 1976 1980 1984 1990
Mainframe only Catalog price $6,100 $9,125 $13,435 $19,500
2014 value $25,320 $26,150 $30,540 $35,230
Mainframe with 2 × 7A19,
7B85, 7B80
Catalog price $9,500 $14,275 $21,520 $30,660
2014 value $39,430 $40,910 $48,910 $55,400