Lafayette TE-50 - Page 7

Set FIL VOLTS to “D”.
Set LOAD control to 30.
Set
the
#3
elemental
switch
to
“F”.
All
other
should
be
set
to
“K”.
Insert
the
tube
into
the
7-pin
socket,
which
is
the
correct
one
for
the
6CB6.
Allow
at
least
30
seconds
for
the
tube
to
warm
up.
onan
9.
One
at
a
time,
move
each
elemental
slide
switch
(except
number
3)
to
the
“P”
position.
Tap
the
tube
and
observe
the
leakage
indicator
lamp.
A
steady
glow
when
the
switches
are
moved
to
“P”
indicates
a
short.
Be
sure
to
return
each
switch
to
“K”
as
you
proceed.
NOW—TEST
FOR
QUALITY
1.
Set
Leakage-Quality
switch
to
QUAL.
2.
With
the
#3
elemental
slide
switch
at
“F’,
set
the
#1
switch
to
“P”.
Make
sure
all
other
switches
are
at
“K”.
3.
Read
the
quality
of
the
tube
directly
on
the
“Replace—?—Good”
portion
of
the
scale.
Note:
Tubes
listed
in
the
tube
chart
more
than
once
are
multi-purpose
tubes,
and
are
equivalent
to
several
tubes
in
a
single
glass
envelope.
It
is
necessary,
therefore,
to
test
these
tubes
according
to
each
listing
just
as
you
would
several
different
tubes,
IN
CASE
OF
DIFFICULTY
As
a
helpful
guide
to
the
user
of
this
tube
tester,
we
have
compiled
a
list
of
problems
commonly
encountered
during
the
use
and
operation
of
the
unit.
SYMPTOM:
The
Tube
Tester
burns
out
the
filaments
on,
some
tubes.
CAUSE:
The
knob
on
the
filament
switch
may
have
become
loose
and
shifted
position,
thus
applying
incorrect
voltage
to
filaments
of
tube
under
test.
Make
sure
the
fully
counter-clockwise
setting
of
the
switch
is
aligned
with
letter
A.
SYMPTOM:
The
tester
tests
12
volt
tubes
as
“bad”
even
though
they
are
known
to
be
“good”.