Sequential Split-8 repair

[>>>marjan<<<]

> in control voltage to all the 3394's(pin 2).  The voltage goes through a
> 4051 and then gets distributed to a dedicated 4051 for each voice.  All
> voices do the same thing and the signal that gets sent to each one's
> 4051operates linearly.  So why the pop out of each voices 4051?  Weird.

Reading this list I leart that 405x stuff sometimes make some strange
things when they break down. Try to change the mux that goes first.

> 
> Also one of the 5V regulators has a 220 resistor tied from its output to
> its input.  With no load, the output raises up to 7V!  Why did they do
> this(its designed in this way)?

Is it what it reads in schematic or you looked inside?
Maybe it's something like current boost regulator?
Sounds strange, but if that is negative voltage regulator 79xx
they have some problems when they are left without load
(at least what I have experienced).


marjan