ESQ-1 Dead keys - 8 in a row

Hello everyone!

Metal bodies ESQ-1 - has 8 dead keys, starting at middle C, all in a row
Swapped the cable, no change - swapped in another keyed that has other problems, and those 8 notes work, so I assume its not the keyboard IC -

Diodes LOOK fine but I assume that may be the problem? Would it be each individual diode? Anyways pulled the keyboard circuit board out looks fine on the underside besides some normal age related corrosion -

Good place to start for troubleshooting dead keys 1 octave 8 notes?

thanks!
tom

The keybed is connected in groups of 8 keys. You’ll find that those 8 diodes have a common connection to the keybed connector. Have a close look at the solder connections and check for hairline cracks in the PCB traces.
Regards
Pat

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I checked continuity from what I could - will reflow some suspect looking connections and try again!

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