beautypg.com

Vectronics VEC-1016K User Manual

Page 17

background image

Option 1: Calibrating with a Signal Generator or FM-Service Monitor

Set the generator up as follows:
Frequency:

50.0

MHz

Output Level:

10 uV (-90 dBm)

Modulation:

1-kHz tone at 5-kHz FM deviation


Connect the generator output to your VEC-1016K antenna jack using a 50-ohm patch
cable. Plug in headphones or external speaker to monitor generator signal.

[ ] Set TUNE to 50 MHz (fully clockwise) and SQUELCH counter-clockwise (open).
[ ] Power the radio and set VOLUME for a comfortable level.
[ ] Slowly tune L4 back and forth with an insulated tuning wand to locate the 50-MHz
test signal.

Important Note: The receiver's 10.245-MHz local oscillator's generates a 5th harmonic
on 51.225 MHz. If you tune across this signal, it will be heard as a strong unmodulated
carrier. Don't mistake this signal for your signal generator's output signal!

Option 2: Calibrating with a Antenna Analyzer

Any MFJ or Autek antenna analyzer with VHF coverage may be used to generate an
alignment signal. Set the analyzer to 50.0 MHz and position a few feet from the VEC-
1016. Do not connect the analyzer directly to your VEC-1016, or damage may result.
Install a 47-ohm resistor on the VEC-1016K antenna jack and follow the test procedure
outlined above for using a signal generator.

Option 3: Calibrating with a Frequency Counter

Your VEC-1016K features a buffered test point for measuring oscillator frequency with a
digital counter. Locate this point on the diagram below:

FL1

FL2

U1, MC13135

3

Test Point

Connect Counter Here


[ ] Connect the frequency-counter ground lead to a ground point (case or PC board).
[ ] Set the TUNE to 50 MHz (fully clockwise) and apply power.
[ ] Touch counter probe to pin-3 and adjust L4 for a counter reading of 39.3 MHz.