Vectronics VEC-1012K - Manual (Page 17)

VEC-1012K Owner’s Manual
17
TESTING AnD ALIGNMENT
PC Board Inspection: Even the most experienced builders make mistakes!
Before applying power to your kit, give it a thorough QC (quality control)
inspection. This will help you find inadvertent assembly errors that might
prevent the radio from working or cause damage to sensitive parts. Follow this
procedure:
1. Compare parts locations against the parts-placement diagram. Was each part
installed where it is supposed to be? Was the correct value used? Start at
one side of the board and work your way across in an organized pattern.
2. Inspect the solder side of the board for cold-solder joins and solder bridges
between tracks or pads. Use a magnifying glass to obtain a clear view of the
track area. If you suspect a solder bridge, hold the board in front of a bright
light for a better view. All joints should be smooth and shiny, indicating
good solder wetting and flow. Resolder any beaded or dull-appearing
connections.
3. Finally, check all electrolytic capacitors and diodes for correct polarity.
Does the plus (+) polarity symbol on the part agree with the pictorial and
with the silk-screen pattern on the PC board? Is the banded end of each
diode positioned correctly? Also, were your ICs installed so the dot or notch
on the plastic case corresponds with the white dot or marking on the PC
board? Was Q1 installed correctly?
Be sure to correct all errors before moving on. If a careful inspection revealed
that everything is OK, you're now ready for the moment of truth!
Initial Checkout:
To check out your kit you'll need a 9-volt flat-pack type alkaline battery and a 8-
ohm extension speaker (or monaural headphones) outfitted with a 3.5 mm mini
plug. Make sure the radio's power switch is OFF (button out) before loading the
battery. Plug in speaker or phones and turn all potentiometer controls fully
counter-clockwise.
1. Apply power (button in).
2. Turn up VOLUME (right-hand pot) clockwise. You should hear a rushing
sound, indicating the receiver and audio amplifier are functioning properly.
3. Slowly advance the SQUELCH (center pot) clockwise. The rushing sound
should stop abruptly around mid-range, indicating the squelch circuit is
working.
If your radio passed its turn-on test, congratulations! You're well on your way to
success, and ready for pre-alignment.