Some of these organs suffered from bad connector/connections to the
tone generator boards. Try wiggling the associated tone boards. Also
swap a good tone board with a non-working tone board, the pitch will be
wrong, but it will tell you if the other circuitry is ok. Strongly
recommend you get the schematic if you can read one, it will save much
agony.

H. R. (Bob) Hofmann
hugh wrote:
I have an opportunity to get a Lowry Celebration C-500 organ.
Unfortunately it has some problems. I believe that the instrument was
made in the late 1970s.

1. All C# and A# are out. Mutations on the same notes are OK. I
assume that it is in the tone generators some place - possibly even the
same chip.

2. There is weak and distorted sound on pedals and the lower keyboard.
Upper sounds great except for the dead notes.

Does anyone have any ideas on these two problems and would it be worth
fixing?