Fix for partial blue screen problem on TDS-scopes with the newer version of CRT driver board

 

1: Remove the CRT driver assy and CRT from the scope.

2: Cut the left connection  in the circle on the picture.





3: Add two new ground terminals inside the CRT driver compartment.





4:  Add a wire to pin 8 of the HV transformer as seen on the picture.
 The length approximately 3.5 and with a flat pin connector on the other end.





5: Install the CRT driver assy back in the scope.


6; Connect the new wire from the HV transformer to the new ground connector on the rear.
7: Move the ground wire on the CRT rear connector board from the connection on the large board to
 the new ground connector on the side





8: Replace the EPROM, 160-9137-00 on the Shutter board with 160-9137-02.
The new has the same content but is a faster version: -00 = 27C64A-250 and -02 is 27C64A-20
9: Install the CRT and test.

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