1351 mouse no vertical tracking.

[BarryB]

Have two 1351 mice but one has no vertical movement/tracking! Are these easy to repair as I've checked continuity from the DB9 connector to the PCB and can't find any breaks in the cable or broken wires in the mouse. Two of the sensors seem to be covered by a plastic housing on the tracking wheel with no obvious way to remove them, the cover appears to be clipped in but no idea how to pop it off?



Anyone repaired one of these before?

 

[Exilent]

The ic is dead, and there not easy to find.

 

[SteveDay]

Not necessarily the IC ... See this 1351 mouse repair:
http://cyborgyn.blogspot.com/2014/12/repairing-commodore-1351-mouse.html

On this one the horizontal tracking wasn't working. He viewed the mouse emitters with a smartphone camera (which lacks the infrared filter present in more expensive digital cameras) and found one emitter was much dimmer than the others. Using an oscilloscope he found the supply to that led was lower than the others, and the voltage to all led's was through separate pull-down resistors ranging between 5.5Kohm and 12Kohm. He simply changed the resistor for the weak emitter and brought it up to the levels of the others.

 

[Bryce]

Do you have a scope or any further test equipment? Don't try to open those plastic housing unless you know it's broken, and that can be tested without opening them.

Bryce.