Floppy Controller board

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chuckphd53
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Floppy Controller board

Post by chuckphd53 »

The original Floppy controller board supports the 5.25 drive supplied with the standard IBM PC JR.
Over the years there have been may very creative folks offering solutions to enhance the JR with more add on drive ability.
Look to the Hardware Custom Designs by Users forum for these items.

TIDBIT:
If you look close at the chip ZM6 directly under the large chip on the board, you will see a filter cap nicely tacked to the top side.
No doubt that during production the IBM Engineers realized they had left off a crucial filter cap on this chip.
This is the DATA 0-7 Bi-Directional chip for the board, and I am sure they had issues with reliable signal integrity at the higher speeds
and needed to properly filter power to this chip, and the best way was to tack solder the local filter cap to the VCC and GND pins on the chip.
Imagine the conversations the 'bean counters' had discussing having to TOUCH each board manufactured and its associated cost ! :lol:
To be fair all engineers have these moments in their designs, hopefully they are caught at the proto stage before manufacturing. :roll:


Here here is a picture of the Jr Floppy Controller board

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“I never commit to memory anything that can easily be looked up in a book.” (AE)
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