Model 5254A; Specifications For; Operating Procedure - HP 5254C Operating And Service Manual

Model 5254C
Section VII
SECTION
VII
MODEL
5254A
AND
5254B
7-1.
INTRODUCTION
7
2
The
HP
Model 5254A
is
basically the
same
as
the
HP
5254B.
The
HP
5254B
is
an improved version
of
the
HP
5254A.
The
differences are
in
the frequen-
cies
measured, and circuit
changes
in
A1 Multiplier
Assembly
and
A5
Video Amplifier Assembly.
Also,
MP1
Cavity
Assembly
has a
slight
gearing change.
The
video external output
appears
at
plug -in
connec-
tor
P6(46)
and
is
supplied to
AUX A
jack on counter
rear panel.
7-3.
To
adapt this
manual
to
Model 5254B
proceed
as follows:
a.
Change
all
5254C model
number references to
5254B.
b.
Change
all
low limit
operating frequency refer-
ences to
200
MHz.
c.
Page
6-7,
Table
6-1:
Change
MP2
to
05254-
2063.
d.
Page
6-6,
Table
6-1:
Change
05254-6026
to
05254-6019.
e.
Page 6-6,
Table 6-1:
Change
05254-6027
to
05254-6023.
f
p
a ge
6-7,
Table
6-1:
Change
MP4
to
05254-
2056.
g.
Page 6-8,
Table
6-1:
Change 05254-2074
to
05254-4003 and delete
(COATED).
h.
Page
6-7,
Table
6-1:
Delete
from
MP4
05254-
2073 description
"OPTION
A85".
Delete
MP16
05254-2076.
7-4
The balance
of this
section
discusses
the differ-
ences in
the
HP
5254A
specifications,
operating pro-
cedure
adjustments, troubleshooting, and circuits.
Changes
in
parts
list,
schematic diagrams
and
com-
ponent location are also given.
These
apply
for
HP
5254
A' s
with
serial
number prefix
51 4-.
7-5
For older
HP 5254A
converters with serial
pre-
fix
number
429-,
or 415-,
Paragraph
7-18
outlines the
changes required in this
section.
7-6.
DESCRIPTION
7-7.
The
HP
5254A
converts a
Hewlett-Packard
Electronic counter into
a direct
reading counter
from
3 to
3.
0
GHz
with
an input
voltage
range
of
50
mV
to
IV rras.
The
stability
and accuracy
of
the basic
coun-
ter is
retained by multiplying a
10-MHz
signal,
derived
from
the
1-MHz
internal
time base
of
the counter, to
a selectable
harmonic
frequency
between
.
3
to
3.
0
GHz.
This
known
harmonic
of
50
MHz
is
then he eio
dyned with
the input signal. If
resulting difference
frequency
is
between
1
MHz
and 53
MHz
(bandwidth
of
A5 Video
Amplifier),
it
is
counted and displayed by
the counter.
The
frequency
of
the
JNPUl
'
sjgjaj 1S
then indicated
by the
combination of
the
MIXING
FREQUENCY
control
on
the front
panel of
the plug-in,
and the
counter display
in
megahertz.
A
front
panel
Level Meter,
by monitoring
the difference
frequency
output to
the counter, aids
in
selecting the
desired
MIXING
FREQUENCY
and also in
determining
ii
input
signal
amplitude
is
adequate
for
accurate frequency
measurement.
7-8.
SPECIFICATIONS
7-9.
Table
7-1 contains
all
technical specifications
for the
HP
5254A
when operating in
an
HP
counter.
Table
7-1.
Specifications for
5254A
RANGE:
.
„
.
As
a converter for
an
HP
Electronic Counter,
300
to
3000
MHz.
ACCURACY:
Retains
accuracy
of
an
HP Electronic Counter.
INPUT SIGNAL LEVEL:
50
mV
rms
(-13
dbm
in
50
ohms)
to
IV rms
(+13
dBm
in 50
ohms).
INPUT
OVERLOAD:
Input
power
in
excess
of
100
mW
(+20
dBm
or
2.
2V rms)
may
damage
the
converter.
INPUT IMPEDANCE:
Approximately
50
ohms.
INPUT CONNECTOR:
Type
N
female
LEVEL INDICATOR:
Meter
aids
frequency
selection; indicates output
voltage
level to
counter.
REGISTRATION:
Counter display
in
MHz
is
added
to
the
converter
dial
reading.
WEIGHT:
.
„ .
Net,
5
lbs
(2, 5
kg);
shipping
7 lb
(3,
2 kg).
7-10.
OPERATING
PROCEDURE
7-11.
Figure 7-1
shows the
Frequency
Measurement
Procedure.
Amplitude
specifications
for the
HP
52 54
A and
HP
5254B are the
same.
7-12.
ADJUSTMENTS
7-13
The
circuit
adjustments described
in
Para-
graphs 5-36 through
5-43 are the
same
for
both the
5254A and
B.
However, Meter High Frequency ad-
justment capacitor
A5C19
in
the
HP
5254B
is
num-
bered
A5C21
in
the
HP
5254A with
A5R17
is
not used.
7-1