TEK TDS3034B Power Supply Repair

[richsf]

In case it helps someone else:

The Artesyn 15V Switching Supply used the TCDT1103G opto, but I ordered the CNY17 based on the reverse engineered schematic that is here on other posts.  I used a socket to reduce future wear and tear on the PCB.  The wrong Opto order resulted in some required adjustments as follows.

   Replacement Part: CNY17   Original Part: TCDT1103G (G=Wide)
 Has a base connection on pin 6     Pin 6 is a N.C.

      * Modified machine pin IC socket into two 3-pin sips for pcb pattern width match
      * The PCB has pins 5 & 6 connected, OK for the TCDT part, not for CNY17
      * Bend out CNY17 pin 6 to get CNY17 Opto to work
      * PCB Pattern is for a Wide DIP  0.4" not 0.3" like normal DIP
      * Shape the pins of the CNY17 to work with the wide spacing

As it turned out, the OPTO was not the bad component. 

I had also ordered the TL431 part (the TO-92 type package)
   * TL431 replaced, fixed
   * The scope is now operating correctly

Note to self:  I should have checked the on PCB opto part number before ordering and should have understood the wider package issue.  The CNY17 also has a 0.4" wide package option.