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Tektronix 7A12
120 MHz dual channel amplifier
7A12 front view

Compatible with 7000-series scopes

Produced from 1969 to 1974

Manuals – Specifications – Links – Pictures

The Tektronix 7A12 is a 120 MHz dual-trace vertical plug-in for 7000-series scopes.

Switches on the front panel control miniature relays in the signal path, such as those selecting input attenuators, through logic circuits. It uses the 155-0032-00 as a gain stage and the 155-0022-00 for channel switching.

The 7A12 was designed by Roy Hayes (who also designed the 3A3 and 3A8 before leaving for HP Loveland in Jan 1971). The Evaluation Engineer for the 7A12 was Peter Starič, co-author of the book "Wideband Amplifiers" with Erik Margan.


Bandwidth 120 MHz (79xx) / 105 MHz (77xx) / 55 MHz (74xx)
Deflection 5 mV/Div to 5 V/Div (1–2–5), variable up to 12.5 V/Div
Input impedance 1 MΩ // 24 pF
Maximum input 5 V (0.5 W) − no damage below 10 V (2 W)
Timing Delay difference between channels < 500 ps
Channel Isolation At least 3000:1 at 75 MHz
Maximum Input Voltage 350 V DC + Peak AC at 1 kHz or less