Vectronics VEC-1016K, Руководство пользователя, Страница: 18 / 23

Important Note: The VFO signal will fall 10.7 MHz below the receiver's operating
frequency and may by too weak for some counters to sample (around -25 dBm). If you
don't obtain a stable counter reading, use a different method of calibration.
Option 4: Calibrating with a Scanner Receiver
You may use a synthesized scanner or extended-coverage HT to pick up the radio's
oscillator signal. Set the scanner to 39.3 MHz and position it near the kit.
[ ] Set
TUNE to 50 MHz (fully clockwise if you have no cabinet), and apply power.
[ ] Slowly adjust L4 until the oscillator signal is heard on the scanner at 39.3 MHz.
Option 5: Calibrating with an off-air signal.
If no other option is available, you may calibrate L4 using the signal generated by a 49-
MHz consumer wireless product. To do this, you should know the product's operating
frequency (check the operating manual or look for a crystal with a frequency marked on
it). Your radio should be mounted in its case so the front-panel tuning-dial scale is
available. Begin by connecting a speaker (or phones) and an antenna.
[ ] Set the
SQUELCH pot fully counter clockwise (open).
[ ] Apply power and set the VOLUME pot for a comfortable background-noise level.
[ ] Adjust the TUNE pot to correspond with the product's assigned operating frequency.
[ ] Slowly tune L4 until you receive the signal at the correct spot on the dial.
Aligning L1, L2 for maximum receiver sensitivity:
If coils L1 and L2 were formed and installed according to instructions, your radio should
operate with near-maximum sensitivity and require no further adjustment. However, if
you wish, you may "tweak" these two coils to optimize performance on weak low-power
signals. In order to make this adjustment, you'll need a weak signal source. This could be
a 1-uV 49.5-MHz signal produced by a signal generator, or a weak off-air signal with
audible background noise present. To adjust, use the blade of a non-metallic tuning wand
or your fingernail to expand or compress the spacing between turns. Note that adjusting
L1 and L2 may change the radio's operating frequency slightly. To compensate for this
interaction, readjust
TUNE as you make each change to ensure the signal remains tuned
in.
Reduced background hiss and lower distortion indicates an improvement in signal
strength. As you find the best point for each coil, stretch or compress it permanently into
in that position.
Don't attempt to adjust L1 and L2 while tuned to a strong local signal.
Use only a weak signal with clearly-audible background hiss. When peaked, the VEC-
1016 should render "solid copy" with good quieting on FM signals of .5 uV or less.