I fixed a porta 02 recently where the seller said tracks 2 and 3 didn't work. Sure enough, the wires were busted off the play side of the head. Easy fix. It's the two white wires in the middle
Yeah preferably lint free cotton swabs but you can worry about that later. I use 91% isopropyl alcohol and cotton swabs. You want to rub the heads side to side in the direction of the tape travel. Don't put any alcohol on any rubber parts.
Turns out something isn't quite right with the 2SA1359. it's causing a weird oscillation. I just swapped the dc in board from a different machine with a 2SB891 and no oscillation. Time to dig a little deeper
Edit: nevermind I fucked up the pin out
Alright I pulled a couple DTC124ES from a parts machine ( dca 55 identifies them as "digital transistors") and swapped one in for Q507 but it didn't change anything. record light is still on all the time. Guess I'll chuck it back in the box and have a think
This is really cool. Good job trying an unconventional solution and figuring it out. I was fully expecting you to fumble this but it looks great. Kinda looks to me like it could be a little more blue even but I dig that grey blue as well