Service manual

OPERATING CONTROLS, INDICATORS AND CONNECTORS (Cont.)
SECTION 6
KEYBOARD MAINTENANCE AND ADJUSTMENT
6.1 CONTACTS
6.1.1 DIRTY CONTACTS
The J-wire switch contact to the buss bar may
become dirty or corroded. If so, use ordinary rub
bing alcohol (isopropanol) on a cotton swab to
clean the contact area. Do not spray contact cleaner
onto the key contacts or use abrasives (emery paper
or burnishing tools) as they will remove the gold
plating. Be careful not to bend the J-wires (fine
whiskers). Stubborn cases may require cleaning
with a nonabrasive rubber eraser. If the contact
area has been damaged, rotate the buss bar or J-
wire or gently bend the J-wire laterally to contact
a new portion of the buss bar.
34
CAUTION
Do not touch J-wires or buss bar
with bare fingers as salty, oily finger
prints will eventually cause corrosion
and dust collection resulting in inter
mittent operation.
6.1.2 CONTACT HEIGHT
Dirty contacts are revealed by improper trig
gering of notes. Triggering problems may also occur
if the contact height (the distance tip of key travels
downward before the note sounds) is set too high
(i.e., makes contact too soon). Black keys should
make contact between 1/8 and 3/16 inch of down-