CRYSTAL
Ct£CK
C.
IIIf
TUNER
•
©
,nnn,-,nn
,
U.'-'
U
'-'
U
'-'
$_.....,co
...
<&
."
...
<0
•••
"
...
0 0 0
0
0
I I
II
I i
."
'"
DIGITAL
IllEAOOUT
SElECTOR
•
co
co
co
",,··:0:·
I
II
I
OJ
OJ
OJ
OJ
MODEL
DigITaL
III~ADOUT
I
....
UT
SIGNALS
ca
••
,,,,,,,
,
..
"
.'
"
(--
m
Pi8.
8-Cmltrol
Selup
(or
Cryslal Check.
TM
CRYSTAL CHECK function allows any crystal
witb a fundamental frequency
of
1·20
MHz
to
be
inserV:'d
into
the
front panel universal crystal socket
to check for crystal activity.
Tbe
crystal will
be
made
to resonate
at
its fundamental operating frequency.
To
perfonn
tbe
external CRYSTAL CHECK:
1. Insert
the
crystal to
be
tested
into
the
front·
panel lOcket marked CRYSTAL CHECK.
2.
Seled
the
EXT XTAL position
of
the
DIGITAL
READOUT SELECTOR.
3. Read
the
fundamental crystal frequency on
the
OlGITAL READOUT.
Defedive
or
inoperative
crystals will be indicated by
an
intermittent
or
a
RF
WATTMETER
WARNING:
The
RF
power
output
should
be checked before making any modulation
or
frequency
test.!!
on
a
CB
transmitUr.
If
the
last three
digit.o
of
the
digital
readout
show a flashing
"888",
the
transmitter ill
providing
more
than
20
Watta
output.
If
this overrange condition is present, imme·
diately
stop
testing until
the
power
output
is reduced
to
prevent damage
to
the
50
Ohm
load, and possible damage to
the
tralWl1itter'a
output
stages.
15
zero frequency readout.
NOTE: Many crystals
used
in
CD
tnms-
eeiven
are dffigned
to
operau
on
an
overtone,
rather
than their fundamental
frequency.
For
example, an O$CilIator
oPtrating
at
27.000
MHz
wiU
~
a
third
overtone crystal with a fundamental fre-
quency
of
9.000
MHz.
This
fundamental
frequency
is
the
one
that
the
CB42 will
indicate.
The
exact
operating frequency
of
the
crystal
depends
on
the
circuit it
i6
part
of.
For
an exact
~ading
of
a
crystal's operations, it should
be
mea·
.Uffld in..::iro:uit with
the
1 Meg fre·
quency
counter
input.
The
RF
WATfMETER
of
the
C842
is designed
to
read
tbe
Peak·Envelope·Power (PEP)
of
tbe
RF signal.
This
allows the
&al11e
meter to read SSB PEP,
or
aver·
age
AM
carrier power.
To
usetbe
RF WATIMETER:
1.
Connect
tbe
transceiver to
tbe
proper power
JOurce as
dC6Cribed
in
the
PREPARING FOR
TEST section.
2.
Connect
the
antenna
output
of
tbe
tran~iver
to
the
50
OHM
input
of
the
CB42 using
tbe
sup·
To Next Page
Loading...
Need help?
General
