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PLL & Transmitter Alignment Points
VRlOOl
&
Deviation
Modulation Level
0
While tuned to the cent�r of the band (145 or 146
MHz), set the AF generator attenuator for 25
mV output at 1 kHz to the external MIC jack.
0
Key the transmitter and adjust VR1001 on the
Motherboard for± 4.5 kHz deviation on the de
viation meter.
0
Reduce the AF injection level to 2.5 mV, and
confirm deviation between ± 2.5 and± 4.5 kHz.
Transmitter S/N Check
AF
Reduce the 1-kHz
with ± 3.5-kHz deviation, and turn on the linear
detector BPF (300 Hz - 3 kHz). Key the transmitter,
and confirm 40dB S/N or better.
V OX Circuit Check
Press FIM � SET� C � C to activate the VOX.
AF
crease the
injection level until the transmitter is
activated (should be <1.6 mV). Press FIM �SET�
C � C again to deactivate the VOX.
Receiver
Set up the test equipment as shown at the right
receiver alignment.
Sensitivity: Interstage Transformers
0
With the transceiver and
both tuned to band center (145 or 146 MHz),
FT-26 Technical Supplement
generator injection to OdB
RF
signal generator
Receiver Alignment Points
VR3001
modulate the RF signal generator with ± 3.5
kHz deviation of a 1-kHz tone, and inject 40
dBµ at the antenna jack.
D
Adjust T1001 through T1004 on the Mother
board for maximum S-meter indication. Then
reduce the injection level to -9 dBµ and confirm
at least 12 dB SINAD.
S-Meter Calibration
While tuned to the center of the band (145 or 146
MHz), inject 20 dBµ and adjust VR3001 on the
Motherboard so that all S-meter segments are just
on.
Receiver Alignment Setup
RF Signal
In
Generator
Alignment
Oscilloscope
AF
Millivoltmeter
SINAD Meter
Speaker
or 8-ohm load resistor
Regulated
l 2V
PSU
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