contact-adjusting screw in until the
to vibrate after the readjustment,
contacts just meet and the reed vi-
perform the troubleshooting pro-
brates
steadily
without sparking
4-4. Trouble-shooting Procedures
b. Replacement of Contact-Adjusting Screw
a. Remove the 115-volt ac, 60-cps power from
and Spring ( TA-248/TT or TA-248A/TT) (fig.
the unit.
(1) Remove the 115-volt ac, 60-cps power
certain that the fuses are not defective, and are
from the unit.
( 2 ) R e m o v e the contact-adjusting screw
b y turning it counterclockwise. Re-
c. Make certain that the incandescent lamp
move the spring with the contact-ad-
is securely tightened in its socket.
justing screw.
d . Check the ac power cord and plug for
( 3 ) Place a new spring on the contact-ad-
loose or frayed wires or loose or broken pins.
justing screw and replace the con-
tact-adjusting screw by turning it in
a clockwise direction.
(4) Apply 115-volt ac, 60-cps power to the
a. Replacement of Reed in Vibrator-Reed As-
unit.
sembly (TA-248/TT or TA-248A/TT) (fig. 1-1
(5) Adjust the contacts by slowly turning
and 1-3).
the contact-adjusting screw until the
( 1 ) Remove the 115-volt ac, 60-cps power
contacts just meet and the reed vi-
from the unit.
without sparking
brates steadily
(2) Remove the binding post head from
the retaining screw.
e. Replacement of Incandescent Lamp (TA-
( 3 ) Remove the reed from the retaining
2 4 8 / T T or TA-248A/TT) (fig. 1-2).
screw.
(1) Remove the 115-volt ac, 60-CPS p o w e r
( 4 ) Install a new reed and secure it in
from the unit.
position with the binding post head
( 2 ) Remove the cover from the unit.
a n d retaining screw.
(3) Turn the lamp in a counterclockwise
( 5 ) Make certain that the reed touches,
direction and remove it from its
and is in exact alignment with, the
socket.
the oontact-adjusting
contact of
( 4 ) Place a new lamp in the socket and
straw.
t u r n it in a clockwise d i r e c t i o n to
(6) A p p l y 115-volt ac, 60-cps power to
secure it in its socket.
the unit.
( 5 ) R e p l a c e the cover and secure it in
( 7 ) Adjust the contacts of the vibrating-
position over the unit.
reed assembly by backing out the con-
( 6 ) Apply 115-volt ac, 60-cps power to the
t a c t - a d j u s t i n g screw until the reed
unit.
i s motionless; then slowly turn the