O W E R M Ete R Ad J U St M E N Ts Wi T H Ca Libr Ato R; With Calibrator - HP 435B Operating And Service Manual

M
odel 435 Β
Adj ustments
5-9. P
OWER METER ADJU STMENTS
W
IT H CALI BR ATO R
REFERENCE: Service Sheets 2 and 3.
If the ad
j
ust me nts are to be conside r e d va lid, t he
P
ower Meter
mu st have α
h
alf- h o ur wa rmup a nd
t
he line voltage mu st be
wi thin +5 to -10% ο of
n
o minal .
DESCRIPTION :
1. The Balance control is centere d to r e m o v e the do offset introduced by
t
he Auto
Zero circuits.
2. The DC Offset co n tr ol removes any do voltage introduced by the DC Amplifier.
3. The CAL ADJ co ntrol is
u
se d to set α level of+1.00 Vdc at rear panel RECORDER
OUTPUT
j
ac k
w
ith α full scale input from
t
he
M
odel 11683Α Range Calibrator.
4. The
M
ete r co ntrol sets the meter reading to full scale when the RECORDER
OUTPUT l eve l is +1.00 Vdc.
5. The Auto Ze ro Offset adjustment removes any do voltage that
i
s introduced by
t
he
Auto Ze r o c ircuits while the ZERO switch is presse d.
6. Th e B a lance control centers the Auto Zero circuit's output voltage range. The Auto
Zero output is
f
orced to its negat ive extreme. The Balance Control sets the
RE CORDER OUTPUT voltage below the center (+1.00 Vdc) by one-half
t
he total
possible voltage swing.
R
A
N
G
E
CA
L I
BR
ATO
R
435 Β
P
O
WER ME
T
ER
ΝΟΤΕ
RE
CO
R
D
ER
O
U
T
PU
T
(RE
A
R P
A
N
EL)
v 10
_11%,
EQUIPMENT: Digital Voltmeter . . . . . . . . . . . . . . HP 3455A
Range Calibrator . . . . . . . . . . . . . . HP 11683 Α (ONLY)
2. Set the Power Meter
s
witches as
f
ollows:
CAL FACT OR . . . . . . . . . . . . . . . . . 100%ο
RANGE position . . . . . . . . . . . . . . . fully cw
POWER REF . . . . . . . . . . . . . . . . . . OFF
DIGITA
L V
O
L
T
ME
T
ER
F
igure 5-5 .
P
owe
r M
eter A
d
j
u
stme
n
t Setu
p
wit
h
Cali
br
ato
r
PROCEDURE:
1. Set the Power Meter LINE switch to O FF a nd adjust the mechanical Meter
Zero control for α meter reading of zero.