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Tektronix 2465A Oscilloscope Repair - Part 12

 

Tektronix 2465A Oscilloscope Repair - Part 12

Filed in Tektronix 2465A on Jan.29, 2018

CAL07 – Readout Centering and Gain

CAL07.PDF

We are near the end of the poor man’s calibration of the 2465A Oscilloscope.

CAL07 adjust the position of the Readout characters on the screen.  They are simply moved with two controls (R2918 and R2931) to place them just inside of the graticle area of the screen.

 
CAL07 – Readout Centering and Gain

The adjustments are on the small card accessed from the top of the scope opposite the CRT.

 
Readout Position Adjustment Location

 

 
Readout Position Controls Close Up

Once the display is centered, it is time to move the CAL Jumper back to the “NO CAL” position.

The second half of this procedure seems to be adjusting the Limited Bandwidth parameters with the 20 Mhz Bandwidth Limit turned ON.

The adjustment is coil L644.

 
L644 Location

 

 
L644 Close Up

I simply applied a 100 Khz, 5 division square wave and adjusted for the flattest waveform.  No problems here.  I did not get a picture of the waveform.


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