Section II. OPERATORS CONTROLS AND INDICATORS
I m p r o p e r setting of the FILAMENT RANGE switch (fig. 3) or
incorrect operation of the PRESS TO TEST switches may damage
the tube under test. Be sure that all the controls and switches are
set properly before inserting the tube in the socket.
a. Controls.
Function
Control
ON-OFF switch . . . . . . . . . .......... In ON position, applies ac power to unit.
PRESS TO TEST (switches P1 Depending on type of test selected, de-
pressing one or more switches applies
through P6).
power to tube under test.
SHORT TEST (6-position rotary In OPER. position, permits all tests ex-
cept short test. By turning switch
switch ).
successively through positions V, W,
X, Y, and Z, various tube electrodes
are tested for interelement shorts.
Switch
FUNCTION (3-position rotary
position
Action
TEST ---------- Permits all types of tube
switch).
Note. On some equipment this switch
tests except voltage reg-
is marked LEAKAGE VR.
ulator and leakage tests.
VR--------------- Permits tests of thyra-
trons and voltage regu-
lator tubes in conjunc-
tion with PRESS TO
TEST P5 switch.
LEAK . . . . Permits determining in-
terelement leakage in
megohms as indicated
by PLATE meter.
Seven SELECTORS switches:
Turning each of the filament switches to
FIL- and FIL+ 12-position
rotary switches.
one of positions 1 to 9 connects fila-
ment voltage to correspondingly num-
bered base pin of tube under test. (0
is no connection.)
Turning the switches to position A or B
connects filament voltage to A or B
electrical clip, respectively.
GRID (12-position rotary switch) - When set to one of positions 1 to 9, con-
nects grid bias and signal voltage to
correspondingly numbered base pin of
tube under test. (0 is no connection.)
In A or B, connects grid bias and
signal voltage to A or B electrical clip.
