I'm restoring STTNG and noticed a couple of existing board mods on the back of the DMD control board. I'm winding if anybody can comment on them and whether they should be left in place or removed. The first pair are at J603. Pin 11 and pin 9 each have a 100 ohm resistor between them to ground. The other is a jumper between U18 pin 3 and U11 pin 13. Any insights are appreciated. Thanks.

Maybe a false alarm. I dug up a schematic for this board and both look like there are supposed be as wired. The components I thought were resistors appear to be unpolarized caps, 100 pf. Schematic shows them as C5 and C8, but those components are missing from my board, so looks like they were added later to the underside. It also looks like U18 and U11 should be connected as described, so maybe there was a broken trace that was bypassed as opposed to repaired.

Yeah, should have done that in the first place. Here's a couple. Thanks much

IMG_1228_(resized).JPG

IMG_1229_(resized).JPG

IMG_1231_(resized).JPG

Thanks for the reply Chris. The two caps are listed in the schematic and they are also showed mounted to the board in my STTNG manual. However, they aren't there. Not sure if some versions were made without, then the "outdated" board were depleted with the components added manually to the back side. The jumper between U18 and U11 was also in the schematic. I checking my board and the front side had a trace from U18 to some other chip, I don't remember which. Anyway that trace was cut and the back side jumper connected U18 and U11. So, as you recommend, I'm going to leave them as is. Thanks again.