• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Mitsubishi linear tracking turntable repair

Thread starter #1
i have a 1981 Misubishi linear tracking turntable with photodiodes with code SP254FS. One is damaged and i am trying to source a modern equivalent. Any help would be greatly appreciated.


Active Member
I'd expect any general silicon photodiode to work reasonably; it's just finding the one with the largest area, that will fit in the appropriate location.

For an infra-red source, these look pretty good:

Or these, for visible light:

Although a lot of the specs for those assume use in reverse leakage mode, they do give an open-circuit voltage figure, which shows they can be used in "photocell" mode which appears to be what that circuit may need.

They are cheap enough to have a go, anyway.

My only other thought is that if they are for the arm tracking system rather than one of the general detectors, replace both with the identical part to maintain the "balance" of the servo system.

Latest threads

EE World Online Articles