Tektronix 2230 Digital storage oscilloscope

Introduction

On my home workshop I use old but great Tektronix 2230 storage scope for measuring electronic DYI hobby projects. On this page I collect some tips for it's advanced use cases.

Tektronix 2230 DSO

Using delayed B Time Base

Delayed B Time Base act as zoom-in tool. It allow look at part of trace more detailed. To use this feature, do following steps:

  1. Obtain trace on display. Switch HORIZONTAL MODE control to BOTH position
  2. Set B TRIGGER LEVEL knob to fully clock-wise position, marked as B RUNS AFTER DLY
  3. When second trace appear on display, move first trace up and use A/B SWEEP SEP control to space both traces verticaly
  4. Now pull B SEC/DIV knob and rotate right. You may see B SEC/DIV info at right-bottom display
  5. Use B DELAY TIME POSITION knob to move highlighted area on first line to select what trace portion is displayed at second trace. Delay time is displayed on top-center portion of display

Saving Reference waveforms

In storage mode, up to three waveforms can be saved to memory to compare them with actual trace.

Storage mode controls

Storage controls, part 1

On image above, you see Storage control buttons - it's have two modes: In MENU mode they are used for walking through menu structure (bottom arrows). In WAVEFORM REFERENCE mode the MEMORY buttons select memory 1 - 3 and SAVE REF button is used for storing Waveform Reference to memory.

Storage controls, part 1

On image above, you see second part of Storage controls - Cursors selection knob and button for changing it's mode and ACQUISITION control buttons.

Save waveforms to memory

  1. Obtain trace on display. Set STORE mode
  2. Press SAVE REF button, on display is choose memory 1 - 3
  3. Press MEMORY 1 button, trace is saved to memory 1 and on display is now original trace A and stored trace

Repeat those steps to save waveforms to memories 2 and 3:

Working with Reference waveforms

Reference waveforms can be turned on/off using DISPLAY ON/OFF buttons 1 - 3. When you need move cursor to another waveform, press SELECT WAVEFORM button and use cursor selection knob. Waveform with cursors is underscored on display:

Managing Reference waveforms

Waveforms in memories 1 - 3 are losted, when scope is turned OFF. So on menu is simple manager, that allow to store REF waveforms to NVRAM - there are 26 positions labeled A - Z.

Also is possible to delete or protect memory positions. Free memory is displayed as 0, full as 1. Use cursor selection knob to walk through memory positions and button on knob to confirm operation.

Save waveform to memory in 4k mode

In 4k acquisition mode, a choice may be made to save the entire 4k acquisition or the 1k display window. To save 4k acquisition, press SAVE REF, then press DISPLAY ON/OFF 1twice.

Working with Reference 4k waveform

Working with Reference 4k waveform is similar as in 1k mode: you can turn waveform OF/ON or move cursors between A and 1:4k waveform

To save only the 1k displayed window, press SAVE REF, then press DISPLAY ON/OFF 1 and then DISPLAY ON/OFF 2.

Capacitance and Inductance Measurements Using an Oscilloscope and a Function Generator - Sine wave method

Measuring using sine wave

Tektronix published Application note, that describes, how to measure L and C Using an Oscilloscope and a Function Generator. I tried this method for measuring some inductors and capacitors. Some ugly math equations I put to spreadsheet for fast computing.

Capacitance Measurement - 10nF

Measuring capacitor 10 nF

Capacitance Measurement - 1µF

Measuring capacitor 1 µF

Inductance Measurement - 10 mH

Measuring inductor 10 mH

Inductance Measurement - 100 mH

Measuring inductor 100 mH

Capacitance and Inductance Measurements Using an Oscilloscope and a Function Generator - Square wave method

On this video is described another method for for measuring inductors and capacitors.

Tektronix 2230 DSO + Tektronix CFG280 Generator Measuring using square wave

Capacitance Measurement - 1nF

C = t/R = 1.29µs / 1000 Ω = 1.29nF. Fixture parasitic capacity is 0,18 nF, so real capacitance is 1.1nF

Inductance Measurement - 10µH

L = 1 / (2π * f) 2 * C = 1 / (2π * 1.448 MHz) 2 * 10 nF = 11.4 µH

Cursor potentiometer replacement

I have had issue with my second Tek's 2230 crappy cursor potentiometer. Moving cursor over screen was unreliable and as I found info on internet, this is common failure of those devices. Fortunately, I have third Tek 2230 with broken front panel, so I decided to use it's potentiometer and swap it between scopes. Here are some pic's from this operation.

As you may see on images, it is necessary remove push-buttons from digitizing board and remove cursor knob using 1.5 mm hexagonal tool. Then is possible open digitizing board and replace dual 10k potentiometer.

Tektronix logo and wizard image

With old sysrom version, you can see in menu chooses to display nice Tektronix logo and wizard image. On new (I have 14) versions this option is missing.

Links external link

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