Casio CT-6500 - board not working?

[nanocyde]

Hello faithful Casio fans, I recently acquired a Casiotone CT-6500 at the customary rate of $1/lb, it had a problem with the audio cutting in and out or being scratchy and distorted but I fixed that by reseating a ribbon cable, however I have an interesting issue where a whole set of buttons and lights are completely inactive - the chord and rhythm sections mostly:

 

https://ibb.co/D1hNMyf

 

However I can trigger the drums from an external MIDI source and the tempo light between START/STOP and SYNCHRO blinks accordingly. I have a scope and meter, the boards look in pretty good condition but it would be nice to know a good place to start. Thanks!

[pianokeyjoe]

Hi, you mentioned the ribbon cables. Check the cables again. Especially the section of the control panel where the rhythm section is. You may have inadvertently loosened one of the cable in there as that has happened to me with my unit that was wayward.

[Chas]

On 7/20/2023 at 8:53 PM, nanocyde said:

 

However I can trigger the drums from an external MIDI source and the tempo light between START/STOP and SYNCHRO blinks accordingly. I have a scope and meter, the boards look in pretty good condition but it would be nice to know a good place to start. Thanks!

 

It's possible that its MIDI is set to "Slave" mode. That means  that rhythms and accompaniment can only be triggered (clocked/ stopped and started) via an external MIDI source. 

 

Check the manual to see if it has a way of setting the MIDI mode. If it doesn't have a MIDI master/ slave setting, then it's probably hardware related and could be another ribbon cable that needs re-seating.

Edited July 23, 2023 by Chas