old vintage electronics

Greetings, in trouble with search of datasheet on NEC C551E621C. If it correct of course, originaly installed in film camera from 1975, Yashica electro 35 GX, and becuase of it malfunction, logic in lolw light condition dont work correct. If possible, I would really like to understand what this...

Hi, I'm trying to fix a center light dmx CTL-6 of 250w by ACME. The problem was that the light didn't turn on. I opened it and found that the bulb had white spots so I thought it didn´t work. But before buying another bulb I checked the supply voltage noticing that it had 220v. I looked for the...

I need help to id what this piece of electronics does. I goes all the way thru the center. there is a button on top like push button not a on & off, so when you push its on and as you let off it stops. So I plugged it in and pressed the button I hear a hum as soon as I let off it stops. the...