HP 4262A User Manual

Model 4262A
/ CIRCUIT MODE
v PROCESS AMPLIFIER
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RANGE 7,
0SC 8 SOURCE RESISTOR RESISTOR A3 / 2L
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1 — UNKNOWN-—
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FREQUENCY TEST SIGNAL t
120Hz
/
1KHz
7/
10KHz
|
|
LOW
LEVEL
\
|
@ — — — _RANGE Control— — — I
i-E;';A_S-I
Table
)
_— =2
| L1
POWER SUPPLY
A9 o Signal Selection
? (See Figure 8-8) Low
+5V +5V
' ATOR REGUL.
A
LINE
oo R
AC
{P(——jowm
r
REGUiATOR
:lg_'l'—fizv
I~
D
-2V
REGULATOR P
The input signal €m to the Phase Detector is a
vector voltage representing the impedance of the
unknown device. The voltage components of the
€m signal are detected. These components corres-
pond to the phase angles (0, 7 /2, n or 37/2) estab-
lished by the reference phase signal. Consequently,
the phase detector outputs are voltage components
which represent the resistive, capacitive, or induc-
tive characteristics of the unknown device. The
phase detector output is converted to dc by a
smoothing circuit which adopts the period averag-
ing technique to accelerate transient response to
the input signals. The special combination of this
technique is to speed measurements at the 120Hz
test frequency. An explanation of the period aver-
aging technique is given on Service Sheet 14.
Section VIII
The
Integrator
is
charged
and
discharged
by
input
signals
(dc)
fed
from
the
Phase
Detector.
The
Zero
Detector
notes
the
time
that
the
output
of
the
Integrator
crosses
the
zero
level
and
sends
a
ZERO
signal
to
the
Digital
Section
(A23
Board).
For
accurate
integrator
operation,
an
integrator
Offset
Null
sequence
is
excuted
before
integrator
charging
is
began.
Offset
Null
control
details
are
described
on
Service
Sheet
14.
The
phase
detector
output
is
provided
through
A14U5
and
U6
to
A13
Board
as
an
APAO
(Auto
Phase
Adjustment
Output)
signal
for
the
period
of
the
auto
phase
adjustment.
In
this
sequential
period,
the
reference
phase
signals
are
adjusted
to
minimize
any
phase
error
which
cause
a
measure-
ment
error.
The
operating
principle
of
the
auto
phase adjustment
is given
on
Service
Sheet
14.
TEST SIGNAL
LEVEL
Figure 8-6
Signol Phase jSelection Avto Phase Adjustment
(See Figure{8—8) {See IFlgure 8-8)
PHASE OET E__INTEGRATOR | _ .
A4 lr-a ;IOL—IIL
3R
:
T
|
6R
2L N
I 1 T 2t o
— A2
@ P.D |FILTER 4 32| | To
[ @) 0:0 a [PHASE o |
vCco GEN 2 |
9R T ) |
Q ey ONE ]
SHOT I
|
~Ner
\\015 o |
—— : APAO
Q va us U6 !
Q4 '
1aL a3 1'>_ oy
us L
Q20 }‘ c6 “9:3
APAQ §7 — INTEGRATOR ==
§ c2 20F
\c=—=—=——PHASE DETECTOR =: o3 “UI T vz "
u3
f'/\—‘"_ : 3L
rfl—\oiw.— o ZERO
\ t . To A23
| \ ci :
]
|
\ ! ZERO DET. |
Offset
Nuli
\
(See Figure8-8) ISL ______ 1 8L
|
S1 Control Offset Null
See Figure 8 —8) (See Figure 8—-8)
Table A. Range [Resistor (Rr ) and Source Resistors (Ro) Selections.
Range 1 2 3 4 5 6 7 8
Function
120Hz | 1000xH |10.00mH|100.0mH | 1000mH | 10.00H ] 100.0H | 1000H
Pul [ 1kHz | 100.0uH | 1000,H [10.00mH | 100.0mH | 1000mH| 10.00H | 100.0H
L 10kHz | 10.00uH | 100.0uH | 1000uH |10.00mH {100.0mH| 1000mH | 10.00H
Re. R. SER 109 L0082 1kQ 10kQ 100k
itind FYTY 100 | 1000 | 1ke | 10ke
120Hz | 1000pF | 1p.00nF | 100.0nF | 1000nF | 10.00zF] 100.0uF | 1000uF | 10.00mF
F‘;lll' 1kHz | 100.0pF | 1000pF | 10.00nF | 100.0nF | 1000nF | 10.00uF | 100.04F | 1000uF
c seee 10kHz | 10.00pF | 100.0pF | 1000pF | 10.00nF | 100.0nF| 1000nF [ 10.00#F | 100.0uF
Rz, R PARA| 100kQ | 10k 1kQ 1000 100
"o SER 100k | 10k 1kQ 10052 10Q
Ful- | 120/
scale 1kHz/| 1000m® | 10.00Q | 100.0Q2 | 10002 |10.00k2| 100.0kQ | 1000k [ 10.00MQ
R 10kHz
Re. Ro SER 100 10082 1k 10k 100k
’ PARA 10Q 1000 1kQ 10kQ | 100k
Figure 8-6. Analog Section Block Diagram.
89

HP 4262A Specifications

General

Brand	HP
Model	4262A
Category	Measuring Instruments
Language	English