Heathkit TC-2 - Pilot Lights

(7)
Check
tube
for
short
by
moving
levers
shown
in
light
type
through
the
two
positions
returning
to
the
positions
shown
on
chart.
A
shorted
tube
is
indicated
by
a
steady
glow
of
the
neon
bulb,
Disregard
neon
bulb
flashing
as
lever
switches
are
moved.
It
is
possible
that
some
serious short circuits, such as plate to iilament, will momentarily overload the power
transformer. This condition will be indicated by complete dim out of the panel lamps, Do
not allow the Tube Checker to operate under this extreme condition for any length of time.
Make the test as quickly as possible in order to obtain the desired information.
(8) Check tube for quality test by moving the test slide switch to TEST position after allowing
sufficient time for the tube to reach operating temperature. If the meter pointer falls in
the GREEN scale, the quality of the tube is GOOD.
TO TEST FOR OPEN ELEMENTS, PROCEED AS FOLLOWS:
(1)
Holding
slide
switch
in
TEST
position,
move
each
lever
in
the
TOP
position
(only
those
in
Light type) to the BOTTOM position and return. Satisfactory tube elements (those properly
connected
to
their
pins)are
indicated
by
a
change
in
meter
reading.
The
grid
element
usu-
ally shows a large change, while a screen or plate show only a slight change.
NOTE:
If
the
meter
indication
in
the
quality
test
(step
8)
is
off
scale,
reduce
the
meter
reading
to an on-scale reading by turning the PLATE control, then proceed with the open element test.
TO CHECK FILAMENTS, FILAMENT TAPS, INTERNAL CONNECTIONS FOR CONTINUITY:
Set FILAMENT selector switch to .75. Move each lever shown in dark type through each of its
other two positions. Always move only one lever at a time. Satisfactory filaments, taps and in-
ternal connections will be shown by 2 bright glow of the SHORT test indicator.
MULTIPLE TUBE TYPES:
‘Tubes which contain several sets of elements are indicatedon the chart by a bracket set of list-
ings, one for each test to be made on the tube. The tester is set up according to the tests in
each line and checked through all of the tests as outlined above.
PILOT LIGHTS:
Check pilot lights by setting the FILAMENT selector switch to the proper voltage and inserting
the pilot light in the socket found in the center of the seven pin socket. This is a universal con-
tact-type pilot light test socket and does not require that the lamp be permanently inserted. It
is merely necessary to hold the pilot lamp so that the side wall of the base and the center pin of
the lamp make contact with the corresponding points in the lamp socket.
NEW TUBES:
‘The Heath Company periodically revises the Tube Checker roll chart in order to keep abreast
of
new
tube
releases.
However,
because
of
the
great
quantity
of
new
tubes
being
released
by
manufacturers,
a
customer
will
occasionally
desire
to
check
a
new
tube
before
the
test
data
appears on the’roll chart. The instructions below wili tell exactly how to set up the instrument
for obtaining temporary settings sothat thesenew tubes maybe checked provided manufacturer’ s
data is available.
(a) Note manufacturer's data carefully concerning the base diagram of the pin connections and
filament voltage.
(b) Set the Tube Checker TYPE switch as follows:
‘Type 1 - for low cathode current tubes (below 4 ma} usually diode type tubes.
Page 21