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CRYSTALCHECK CB NF TUNEN
v
/,4
I t-l l-l t1 l-l t-l l-l I f_f . r_f f_t t_t t_l t_l
v/
OELWE CB ANALYZEF
S=IIC)OFIE
L[Iftr
o
o
MHr
NHz
o
o o
D I G I T A TB E A D O U T S E L E C T O R
/,...-.\ .IAN.
.v.
r x r x r A .r | ( F ,
MOOEL
oIGITAL NEAOOUT INPUT SIGIUALS
CB42 off 0lr
Fig. 8-lontrol
)l | .
c n Y s T Act H t c t ( -
Setup for Crystal Check. zero frequency readout.
The CRYSTAL CHECK function allows any crystal with a fundamental frequency of 1-20 MHz to be inserted into the front panel universal crystal socket to check for crystal activity. The crystal will be made to resonate at its fundamental operating frequency.
NOTE: Many crystals used in CB transceivers are designed to operate on an overtone, rather than their fundamental frequency. For example, an oscillator operating at 27.000 MHz will use a third overtone crystal with a fundamental frequency 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 is part of. For an exact reading of a crystal's operations, it should be measured in-circuit with the I Meg frequency counter input.
To perform the external CRYSTAL CHECK: 1. Insert the crystal to be tested into the frontpanel socket marked CRYSTAL CHECK. 2.
Select the EXT XTAL position of the DIGITAL READOUT SELECTOR.
3.
Read the fundamental crystal frequency on the DIGITAL READOUT. Defective 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 tests on a CB transmitter. If the last three digits of the digital readout show a flashing "888", the transmitter is providing more than 20 Watts output. If this overrange condition is present, immediately stop testing until the power output is reduced to prevent damage to the 50 Ohm load, and possible damage to the transmitter's output stages.
The RF WATTMETER of the CB42 is designed to read the Peak-Envelope-Power(PEP) of the RF signal. This allows the same meter to read SSB PEP. or average AM carrier power. To usethe RF WATTMETER: 1. Connect the transceiver to the proper power source as described in the PREPARING FOR TEST section. 2.
15
Connect the antenna output of the transceiver to the 50 OHM input of the CB42 using the sup-
v
/,4
I t-l l-l t1 l-l t-l l-l I f_f . r_f f_t t_t t_l t_l
v/
OELWE CB ANALYZEF
S=IIC)OFIE
L[Iftr
o
o
MHr
NHz
o
o o
D I G I T A TB E A D O U T S E L E C T O R
/,...-.\ .IAN.
.v.
r x r x r A .r | ( F ,
MOOEL
oIGITAL NEAOOUT INPUT SIGIUALS
CB42 off 0lr
Fig. 8-lontrol
)l | .
c n Y s T Act H t c t ( -
Setup for Crystal Check. zero frequency readout.
The CRYSTAL CHECK function allows any crystal with a fundamental frequency of 1-20 MHz to be inserted into the front panel universal crystal socket to check for crystal activity. The crystal will be made to resonate at its fundamental operating frequency.
NOTE: Many crystals used in CB transceivers are designed to operate on an overtone, rather than their fundamental frequency. For example, an oscillator operating at 27.000 MHz will use a third overtone crystal with a fundamental frequency 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 is part of. For an exact reading of a crystal's operations, it should be measured in-circuit with the I Meg frequency counter input.
To perform the external CRYSTAL CHECK: 1. Insert the crystal to be tested into the frontpanel socket marked CRYSTAL CHECK. 2.
Select the EXT XTAL position of the DIGITAL READOUT SELECTOR.
3.
Read the fundamental crystal frequency on the DIGITAL READOUT. Defective 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 tests on a CB transmitter. If the last three digits of the digital readout show a flashing "888", the transmitter is providing more than 20 Watts output. If this overrange condition is present, immediately stop testing until the power output is reduced to prevent damage to the 50 Ohm load, and possible damage to the transmitter's output stages.
The RF WATTMETER of the CB42 is designed to read the Peak-Envelope-Power(PEP) of the RF signal. This allows the same meter to read SSB PEP. or average AM carrier power. To usethe RF WATTMETER: 1. Connect the transceiver to the proper power source as described in the PREPARING FOR TEST section. 2.
15
Connect the antenna output of the transceiver to the 50 OHM input of the CB42 using the sup-
