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Tektronix 2465A Oscilloscope Repair – Part 9

Tektronix 2465A Oscilloscope Repair – Part 9

Filed in Tektronix 2465A on Jan.28, 2018

CAL04 – Ch 2 Delay Enable/Disable

For this section, I am simply enabling the Channel 2 Delay function and checking functionality with it enabled.  I could choose to leave it enabled, or to disable it.  I left mine enabled.

 
CAL04 Start

Steps a – d start up the procedure and allowed me to flip back and forth between CH 2 Delay Enabled and Disabled.  After selecting “Enabled” I pressed the A/B Trig button to leave the function.

 
CAL04 Disabled

 

 
CAL04 Enabled

In steps e – f, I set up a narrow pulse at 100 Khz.  Since I do not have a Calibration Generator, I used the pulse output from my Agilent scope’s function generator.  It’s not a terribly fast rise time, but seems to work for this check. The procedure calls for using a dual-input coupler, which I do not have.  I simply used a BNC T to feed both channels with identical length RG-58 cables.

In step g – i, I set the generator to create a 5 division pulse on the screen, then overlapped the two channel traces near the center of the screen using the Channel 1 & 2 position controls. I set the rising edge to the center of the screen with the horizontal position control.  Then I enabled the x10 magnification.

 
Traces Centered

 

 
CAL04 – 5ns sweep

 

 
CAL04 – x10 magnification

Steps j – m had me pull out the SEC/DIV knob to turn on the channel 2 delay function.  Then I used the delta control to move channel 2 forward and back from channel 1, finally returning it to overlap.  It’s hard to see the separation, because my pulse does not rise fast enough, but I was able to see the two traces separate slightly. The photo was taken before I separated the traces.

 

 
CAL04 – Turn Delta

Since I wanted to leave this function enabled, I stopped at this point, rather than returning to the CAL04 menu to disable it.

 


 

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