Wersi CD Series Technical Assistance

We met Karl many years ago in Lancaster, Pa. at a Wersi concert and workshop event. He just sent the following request via e-mail. Who can help?

I have a Wersi CD model Gala with Memory Tower & Golden Gate. It’s a bucket list item for this 84-year-old male NASA senior engineer retiree. As such, it’s an excellent on-going project to bring this instrument back to a playable lifetime of its own. The two previous postings with WersiClubUSA produced outstanding support: 

  1. Purchase of a completely functional Golden Gate via a German Wersi serviceman.
  2. (Most recently) An inside USA purchase of caged central plug-in circuit boards lifted from a functioning Gala.

To this point, Golden Gate boots up perfectly to its play screen and performs all functions generated by my touch screen commands. Likewise, the CD Gala portion sequentially flashes its LEDs until I push any button on the control panel. That is the end: no response from keys being depressed; central display screen lights but controlling the display is not evident because the intensity isn’t controllable, etc.

I expect to concentrate troubleshooting to ICs on the drawbar boards…(the controlling section). I replaced EPROM ICs on both the Master processor and co-processor (MST8 and CO 1) with those provided by Golden Gate. However, I have somehow mixed the 3-sets of these ICs. Thus, I plan to replace these trial/error.

Any comments, advice, or other support from club members will be appreciated, and I certainly thank you for the assistance to get me this promising point in my Gala Life quest.
Cordially,

Karl