HP 3400 A6 replacement pcb at PCBWay

[Qmavam]

  Just letting you know, a chap has designed a pcb to replace the chopper board, especially helpful when the photo cells have went out of tolerance on your HP3400.
https://www.pcbway.com/project/shareproject/HP_3400A_A6_Chopper_Board_Replacement_06465eb7.html
If you watch the video, keep in mind that board is REV 1,
he got layout errors fixed on REV 1.1!
If you watch his linked video on the PCBWay site, have your finger on the FF button, or I suggest you just start at 31:00.
                    Mike

[TheDefpom]

This was my design, I did it as part of a repair project getting a 1965 version of the 3400A working again.