woodapples
Active member
Yes, i retained the LM317, but i removed the 12v reg for efficiency's sake and combined all 12v rails into one, including the one on the heater, the 12v rails on the deflection IC and the softstart RC circuit in LM317's ADJ pin. I supplied the usb-pd's 20v to the input of LM317 and it seems to work. But i have plans to remove that chip and replace it with a better switching reg with current limiter (my measurements indicated around 17-18v with 0.4A current limit).Cool project, curious to know how you've connected stuff around the LM317?
I think maybe in my final build I was injecting power into the lm317 input.
I'd have to check the schematic but from memory it has soft start circuitry on the adj pin.
I haven't played with my one since I ran out of working classic/classic II logic boards (also I got a Mac plus working).
BTW, thanks so much for your prior project! It was quite a good stepping stone for this effort! Wouldn't have done this without that project post of yours