Vectronics VEC-1002K - Manual (Page 21)

VEC-1002K Owner's Manual 2 Meter FM Receiver Kit
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3. Make a small flag from a scrap of tape and install it on the hex-head tuning
wand. This will help you count revolutions as you adjust L4.
4. Locate tunable-oscillator coil L4. Insert the tuning wand and rotate the slug
counter-clockwise so the top surface is perfectly flush with the top of the
metal shield can. Now, watching the tape flag and counting revolutions,
rotate the slug 6 turns clockwise down into the body of the coil.
5. Set your voltmeter range to 10 Volts dc and connect the black (-) lead to a
ground point on the PC board. Locate pin # 17 on U1 (see below). This is
the test point for adjusting L5.
FL1
Test Point, 2.3 V
U1, MC13135
6. Set all front-panel controls on the radio counter clockwise, install a 9-volt
battery on the battery snap clip, and apply power via the OFF/ON switch.
No antenna should be connected during this test. With power applied, touch
the red (+) voltmeter lead to pin #17. Using a small screwdriver, adjust L5
for a reading of 2.3 volts. No further adjustment will be required.
Final Alignment--Oscillator Coil L4:
Your kit should be mounted in the VEC-1002KC case for this procedure, with its
TUNE knob installed and set to 146.0 MHz. If you don't have a case, set the
TUNE pot to mid-range (12-o'clock position). Make sure your radio is away
from metallic surfaces that could detune it during calibration. Set the PC board
on top of a book if your desk or bench surface is metal. There are several ways
to calibrate your receiver. Choose the method most compatible with the tools
you have available:
OPTION 1: Calibrating with a signal generator or FM-service monitor.
Set the generator up as follows:
•
Frequency: .............................146.0 MHz
•
Output Level:..........................10 uV (-90 dBm)
•
Modulation: ............................1-kHz tone at 5-kHz FM deviation
Connect the generator output to your VEC-1002K's antenna jack using a 50-ohm
patch cable. Plug in headphones or external speaker to monitor generator signal.
1. Set TUNE to 146.0 MHz and SQUELCH counter-clockwise (open).
2. Power the radio and set VOLUME for a comfortable level.