Hi, thanks for this mod! Wiring with only resistors, transistor and DIN socket: https://github.com/KevinSalmon/Casio-CTK-480-MIDI

i got a CTK-495 and wanna connect it to my PC to do more things with DAW. But i don't understand your post because i just start researching these audio things today and also English is not my native language. So can i ask you if it possible for me to connect my CTK-495 to my PC and how? Thank you and very appreciate if you answer my question!

I have CTK-495. I guess i see the PCB board there are two for placing two MIDI connection (IN/OUT). and the others parts still empty. And the board looks similar to the piture above CTK-481 in MIDI section. I wonder what tipe of IC six leg, transistor and typeof diode. I think those parts are difficult to find. Hoping any suggestion for you...thanks...

Hi! I want to do the opposite, add MIDI IN, so I can control my old Casio CTK-550 from Ableton. Do you think it's possible?

Weird. I never got a notification about this comment.

I suppose it probably would work. I thought about soldering that RX pin to the midi board, but I didn't have a good way to test it. I mean, I could midi-out from the computer, but I wouldn't be really sure if it is just the computer not working.

The RX on the CTK-480 is tied to a 22 ohm pullup resistor. The 481 Service manual shows that as a 10 ohm resistor though, and also has a 1K ohm resistor before the RX pin. So, to make the equivalent circuit,  you might need to cut the trace, or lift the RX Pin off the solder pad.