Shruthi-1 not receiving MIDI (fixed)

Hey all,
This is my first Shruthi. Got the kit with the SMR4. I’ve gone through all the troubleshooting tips in the assembly instructions and everything checks out, except I still get no response from MIDI data being sent to the unit.

And yes, I finally plugged the cable into the IN jack as opposed to the OUT jack. Can rule that one out… >.>

Optocoupler (6N13x)in the right direction ?

Yep, an reading the correct voltages at the correct pins.

Can you confirm a slight voltage Drop on Pin 6 when receiving heavy MIDI Data (use the PitchWhell and bend like hell…) - or better can you scope Pin 6?

No drop on pin 6 at all.

pin 5 continuous with ground? diode correctly oriented?

yes and yes.

No drop and pin 5 to GND correctly means the OpAmp isnt working… can you swap to prove?

sadly, no… all the optocouplers I have access to are surface-mounted in other equipment.

Tried another midi cable?

A brand new MIDI cable tried. Still nothing. Ordered a stash of optocouplers from Mouser.

Correct resistors around the optocoupler? too big a value and the LED won’t light enough inside the optocoupler.

using what came with the kit shrugs

After receiving a new batch of optocouplers and it still not working, I took a closer look at the resistors again and found that the brown and red had messed with my colourblindness and I had swapped the resistos for R18-19 with the resistors for R1 and 14. quick swap, and it works wonderfully. \\o/