Amiga Mouse Original Tank Mouse Optical sensor Faulty Help please.

[Pat the Cat]

Not quite. The receiver part is a diode, not a resistor.

So it goes on/off, depending if light is hitting it. Or whatever wavelength.

That's why you need a matching pair - so the correct wavelength gets sent out by the transmitter, and is received by the diode (receiver).

I don't think the originals are legal for sale anymore, brand new. They were not RoHS tested.

But, I guess a compatible pair is easy enough... one side is Light Emitting Diode (OK, might be infra red, not "light" technically.) The other side is Light Receiving diode (and has to match the LED, or close enough).

Other side is Receiving diode, so it only allows a current flow when the right wavelength is hitting it.

So long as they both work at +5V, and they physically fit in the holes and line up with the spinning disk, I guess it doesn't make much difference which matched pair you use.

Easiest probably to hack an old non-Amiga ball mouse for the parts. Should work OK. It's not like the Amiga pairs were special or terribly different, just the connector was wired different, where you plugged it into the computer.

[Pat the Cat]

I know. But I never saw a transistor with two legs. Have you?

Here's a pic of a Logitech mouse PCB, from the same period. Two connectors on the components, two legs.

https://en.wikipedia.org/wiki/Computer_mouse#/media/File:Logitechms48.jpg

Anyway, that's the way I'd sort it. It's not exactly politically correct, but it should work.

Just replacing one side or the other, without knowing the operating wavelength, is asking for trouble. Replace the pair, it doesn't matter, you know they match.

[Pat the Cat]

(shrug) Same difference. Both a two legged transistor and a diode are effectively wired the same, doing the same job. Neither will work if plugged in backwards.

Who cares so long as the buggers work? No, nevermind, I'm done here. I don't want yet another bashing.

[Pat the Cat]

Hi @darkage and @Pat the Cat.

Problem Sorted  ?
The load on the IR Reciever was to low (Original Design) which was 670 Ohms.
Now modified to 2.7K ohms as per Pavel Ruzicka's Circuit.
I have changed all 5 Resistors to this standard.

Thanks for all your help.
Ray

Fix is a fix. :drink: