148NWST Alignment

148NWST ALIGNMENT
REVISION: 1.111
BURKE
.
ALIGNMENT
PROCEDURE
MODELS: 148 GTL
148 GTL ST
148 NW ST
REVISION: 1.111
DATE: 03/11/03
PREPARED BY:
BURKE
Total Pages: 8 pages
Page:1
print date: 3/27/06
148NWST ALIGNMENT
REVISION: 1.111
BURKE
148NWST ALIGNMENT INSTRUCTION
1
TEST CONDITION:
1.0. TEST TEMPERTAURE:
1.1. STANDARD DC POWER:
25 ±5 °C
13.8VDC
1.2. MEASUREMENT CHANNEL:
1.3. STANDARD AUDIO LOADING:
1.4. ANTENNA IMPEDANCE:
CH19 (27.185MHz)
4Ω
50 Ω
1.5. STANDARD RF INPUT:
1.6. STANDARD REF. MODULATION:
1.7. STANDARD REF. AUDIO OUTPUT:
1.8. PULSE GENERATOR:
1mV
CB 30%
SSB 500Hz and 2400Hz
0.5W
1µS pulse @ 100mS and 1V peak-to-peak amplitude,
with rise and fall time of less than 10nS.
1.9. FREQUENCY TABLE:
CH NO.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
FREQ. (MHz)
26.965
26.975
26.985
27.005
27.015
27.025
27.035
27.055
27.065
27.075
27.085
27.105
27.115
27.125
27.135
27.155
27.165
27.175
27.185
27.205
CH NO.
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Page:2
FREQ. (MHz)
27.215
27.225
27.255
27.235
27.245
27.265
27.275
27.285
27.295
27.305
27.315
27.325
27.335
27.345
27.355
27.365
27.375
27.385
27.395
27.405
print date: 3/27/06
148NWST ALIGNMENT
REVISION: 1.111
BURKE
1.9. TEST EQUIPMENT SETUP AS BELOW:
A. TX test equipment setup:
Spectrum
Analyzer
Power
Supply
Dummy
Load
Modulation
Meter
RF
Wattmeter
148NWST
Audio Gen.
B. RX test equipment setup:
AC VTVM
RF Signal
Generator
Oscilloscope
148NWST
Power
Supply
Noise pulse
generator
4 ohm Load
Page:3
print date: 3/27/06
148NWST ALIGNMENT
2.0
2.1
STEP
1
RX mode, AM, CH1
DC voltmeter to TP9
L19
2
3
RX mode, AM, CH19
Same as step 2
RX mode, AM, CH19
Voicelock Midrange
RX mode, LSB, CH19
Voicelock Midrange
RX mode, USB, CH19
Voicelock Midrange
Oscilloscope to TP10
Oscilloscope to TP1
Frequency counter to
TP1
Frequency counter to
TP1
Frequency counter to
TP1
L21
L20
L23
Adjust for 34.985MHz
5
6
2.2
STEP
1
TX mode, AM, CH19
2
RX mode, LSB, CH19
3
RX mode, USB, CH19
3.0
1
2
3
Carrier Alignment
PRESET TO
CONNECTIONS
BURKE
PROCEDURE
Adjust for 3.2V, ±0.1V
Check CH40 = 4.2V, ±0.2V
Adjust for maximum output
Adjust for maximum output
4
STEP
MAIN ALIGNMENT
VCO
Alignment
PRESET TO
REVISION: 1.111
CONNECTIONS
Frequency counter to
cathode of D17.
Disconnect TP7 & TP8.
Frequency counter to
TP14
Frequency counter to
TP14
ADJUST
L22
L59
ADJUST
Adjust for 34.9835MHz
Adjust for 34.9865MHz
PROCEDURE
L31
Adjust for 7.8MHz, then
re-connect TP7 & TP8
L30
Adjust for 7.7985MHz
CT2
Adjust for 7.8015MHz
RECEIVER ALIGNMENT
Connect an AC VTVM across speaker coil.
Adjust volume control to obtain a suitable indication.
Set generator output low enough to prevent AGC limiting.
Preset controls as follows, unless otherwise noted:
RF Gain maximum, Voicelock midrange, Squelch minimum, NB/ANL off, Tone normal.
PRESET TO
CONNECTIONS
ADJUST
PROCEDURE
Output of signal generator through
L7, L8, L9,
RX mode
0.01µF to TP16 (TR15 emitter).
L10, L12,
Adjust for maximum output
CH19, USB
Freq. = 7.8005MHz
L14
NO modulation, RF output 200µV
Output of signal generator through
RX mode
0.01µF to TP15 (FET1 Gate 1).
L15, L13,
Adjust for maximum output
CH19, AM
Freq. = 455KHz, 1KHz 30%
L3
modulation, RF output 100µV
Output of signal generator to
RX mode
antenna input.
L4, L5, L6 Adjust for maximum output
CH19, AM
Freq. = 27.185MHz, 1KHz 30%
modulation, RF output 1µV
Page:4
print date: 3/27/06
148NWST ALIGNMENT
STEP
4
5
PRESET TO
RX mode
CH19, AM
NB/ANL
switch set to
NB
RX mode
CH19, AM
Squelch to
maximum
6
RX mode
CH19, AM
7
RX mode
CH19, USB
4.0
STEP
1
2
3
4
5
6
7
REVISION: 1.111
CONNECTIONS
ADJUST
Output of signal generator and noise
pulse generator to antenna input.
Freq. = 27.185MHz, 1KHz 30%
L1, L2
modulation, RF output 1µV.
Oscilloscope to TP17.
Output of signal generator to
antenna input.
VR3
Freq. = 27.185MHz, 1KHz 30%
modulation, RF output 1800µV
Output of signal generator to
antenna input.
VR1
Freq. = 27.185MHz, 1KHz 30%
modulation, RF output 100µV
Output of signal generator to
antenna input.
VR2
Freq. = 27.186MHz, no modulation,
RF output 100µV
BURKE
PROCEDURE
NOISE BLANKER
Adjust for maximum pulse
amplitude on oscilloscope
SQUELCH RANGE
Adjust until audio just appears
AM SIGNAL METER
Adjust for a reading of 9 on the
analog meter of the CB radio
SSB SIGNAL METER
Adjust for a reading of 9 on the
analog meter of the CB radio
Transmitter Alignment
Maintain a 50 ohm 25 watt dummy load on the antenna connector for the following
steps.
PRESET TO
CONNECTIONS
ADJUST
PROCEDURE
TX mode
L47, L48,
RF wattmeter to antenna
CH19, AM
L46, L45, Adjust for maximum RF output
input
Dynamike minimum
L38
Spectrum analyzer to
Adjust for minimum at 54MHZ
Same as step 1
L36
antenna input
(2nd harmonic)
TX mode
RF wattmeter to antenna
CARRIER BALANCE
CH19, USB
VR7
input
Adjust for minimum RF output
Dynamike minimum
DRIVER BIAS
Same as step 3
Insert ammeter at TP8.
VR9
Adjust for 25mA
FINAL BIAS
Same as step 3
Insert ammeter at TP7.
VR8
Adjust for 50mA
TX mode
RF wattmeter to antenna
CH19, USB
input. Insert a
SSB ALC
VR11
Dynamike maximum two-tone, 500mV signal
Adjust for 12 watts PEP RF output
to microphone input.
TX mode
RF wattmeter to antenna
AM CARRIER POWER
CH19, AM
VR10
input.
Adjust for 4 watts RF output
Dynamike minimum
Page:5
print date: 3/27/06
148NWST ALIGNMENT
STEP
8
9
10
11
PRESET TO
REVISION: 1.111
CONNECTIONS
Same as step 7
BURKE
ADJUST
VR6
Frequency counter to
antenna input.
Modulation meter to
TX mode
antenna input. Insert a
CH19, AM
1KHz, 50mV signal to
Dynamike maximum
microphone input.
Remove the dummy
load. Connect a 100
ohm load to the antenna
CH19, AM
input. Use the built-in
SWR meter to check the
SWR.
Same as step 7
Page:6
VR5
PROCEDURE
RF POWER METER
Adjust so that the needle of the
CB’s analog meter is at the border
between the green and red zones.
TX CARRIER FREQUENCY
Adjust for 27.185MHz
VR501
AMC CONTROL
Adjust for 90% modulation
VR12
SWR METER
Adjust for an SWR reading of 2
print date: 3/27/06
148NWST ALIGNMENT
REVISION: 1.111
Page:7
BURKE
print date: 3/27/06