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Tektronix 1225
48 channel logic analyzer
Tektronix 1225

Produced from 1988 to (?)

Manuals – Specifications – Links – Pictures

The Tektronix 1225 is a logic analyzer that supports 16 to 48 channels, 100 MHz asynchronous, 25 MHz synchronous. It was introduced in 1989. It is equivalent to the Tektronix 1220, the difference being that it has three channels instead of two. It is also very similar to the to the Tektronix 1230 on the outside but on the inside the layout is different. It only has three probe ports instead of four and the boards are stacked horizontally instead of vertically. It was one of Tektronix effort to make an "Ease of use" logic analyzer aimed at students and engineers. The user interface clearly represents that mindset. The menus are simple and there are help guides everywhere guiding the user in what he might want to do.


It uses either P6444 or P6443 16-channel probes.
Number of channels 48 channels
CRT 13 x 10 cm
Power 90-250 V
Weight 8.6 kg (19 lb.)
  • Composite output
  • RS-232 Printer port


The 1225 is built around a 65C02 as the control processor with 104K of SRAM, and 128K of firmware in a bank of EPROMs. There is a separate board under it that manages the display and keypad. It is powered by a same 65C02 CPU, it is using a MC68A45 CRT driver as a display driver. The display has 56K of RAM and 8K of ROM. There are two coin cell batteries that retain settings. The problem is that there is a bug that prevents it from keeping the date after the year 2000. Upon powering it on and off again it will reverts to 19XX. Example: 2018 -> 1918

Easter egg

Their is an "Easter egg" you can activate. When initially powered up the welcome screen shows, press the STOP button and a bar will show up with the programmers names near the bottom of the screen.