Repairing the YAMAHA

W7/W5 disk drive

After reading some instructions how to repair the well-known defect of the disk drive I made a decision to make this „life“ step. After several months of persuading myself that it is not so bad, that I am not a complete idiot and that I must manage, The Day came.

The source of the defect is the information whether there is a floppy disk in the disk drive. This information is provided by the microswitch, on which the disk lands after inserted into drive. I had several possible solutions. The first one was to by-pass the naughty microswitch, either directly or to make parallel connection with another microswitch attached somewhere on the instrument. Next possibility was to resign the write protection and use this microswitch.

When I - after removing several screws - got to the drive, I started with measuring the contact resistance of both microswitches. The functionless microswitch was about 200 ohms, the functional one about 30. Interesting. Maybe it would have helped to rinse the defective microswitch in a cleaning liquid but I had none. So I have decided to replace the functionless microswitch with the functional one. It´s an easy operation in case you have a suction flask.

After I put everything back to its place and tightened all the screws, I eagerly switched the instrument on. The system started, I inserted a floppy disc, an attempt to read, and hooray. No, three times hooray. It´s working. Reading, writing, everything is OK, even the write protection is working but I wonder for how long.

"Action" pictures

	This is my darling (before "the action")	22 kB
	And this is the damned disk drive, it´s fixed with these screws	44 kB
	These are the screws the electronics board is fixed with	62 kB
	These are the microswitches: DISK IN DRIVE on the left, WRITE PROTECT on the right	24 kB
	This is the stupid microswitch which drove me mad hundreds of times having failed to read the floppy disk	3 kB
	Look how nicely it´s working now	13 kB
	One of the screws won´t loose, rough violence is following	39 kB
	Hey buddy, it will never work again	36 kB

The Magical Wire

under construction(translation :-) ...

"Action" pictures

	takhle to vypada zamontovaný	357 kB
	detail provedení kouzelného drátu	391 kB