Boonton 75D Instruction Manual page 61

Table 5.
Equipment Performance Checklist (Cont'd)
STEP ITEM
ACTION OR CONDITION
PERFORMANCE STANDARD
7 . Detector gain
check
a. Check that all front
panel controls are in
accordance with Table 4.
a. None
b. Zero-balance the bridge
as described in para¬
graph 3.5.
b. NULL INDICATOR
pointer dips to within
three subdivisions of
zero on LO sector of
dial scale.
c. Adjust CONDUCTANCE
control until NULL
INDICATOR pointer
deflects upscale to the
second major increment.
Record the pmho reading
on CONDUCTANCE
G-scale.
c. NULL INDICATOR
pointer rests at second
major increment on
meter scale.
d. Rotate GAIN control fully
counterclockwise.
d. NULL INDICATOR
pointer deflects down-
scale toward zero in
LO sector of dial scale.
e. Set CONDUCTANCE
control to zero on G-
scale. If necessary,
zero balance the bridge
as described in para¬
graph 3.5.
e. NULL INDICATOR
pointer dips to within
three subdivisions of
zero on LO sector of
dial scale.
f. Adjust CONDUCTANCE f. CONDUCTANCE dial
control until NULL is approximately 5
INDICATOR pointer times the reading
deflects upscale to the recorded in c, above,
second major increment.
Record the pmho reading on
CONDUCTANCE G-scale
and compare with the reading
obtained in c, above.
75D
b-370
56