beautypg.com

Vectronics VEC-102K User Manual

Page 26

background image

26

5-5.

Make a temporary connection of your antenna or a 10-20' length of any kind
of wire to the short antenna wire near the RF gain control.

5-6. Set the RF Gain trimmer to about 3/4 fully clockwise (as viewed from the

rear of the PC board).


Note: The following tests verify basic receiver performance before installing the PC

board into the cabinet. Because the PC board groundplane and control housing
are not yet grounded to the aluminum panel, you will experience phenomena
during these test that will not occur after complete assembly. In particular, the
regeneration control knob will be sensitive to hand capacitance. In other words,
you can expect changes in frequency and gain when touching the knob, shaft, PC
board ground, etc.

5-7.

Push the DC power switch to its ON position. The LED should glow. (If it
does not, turn off the switch immediately and re-check both the LED and the
battery snap wires for correct polarity.)


Before proceeding, it would be a good idea to re-read our full explanation of the use of
the Regeneration control. Also, look ahead to Step 5-10 regarding adjustment of trimmer
R20. In order to do that adjustment, you first need to experience exactly what
"regeneration" sounds like, which we'll do in 5-8!

5-8.

With the controls set per 5-4, you should be pleased to hear virtually nothing
right now except a faint background hiss! Now, start turning the
Regeneration control slowly clockwise. At some point in this turning, you'll
start to hear "something" (depending on where the tuning dial is set).
Turning just slightly beyond that point will bring in a very distinct hiss or
whistle or perhaps a recognizable radio signal. After adjusting the volume
control to a comfortable level, try rotating the Tuning capacitor. You should
hear radio signals of various kinds.

5-9.

Experiment with Tuning and Regeneration controls on Bands B, C, and D. If
it's after dark, Bands A and B should be very active. In broad daylight, B and
E will have more activity, and Band A will be quieter. Reception on Band E
may require Step 5-10 below.

5-10. Perform a preliminary adjustment of regeneration trimmer R20 as follows:

Turn power OFF.
Set Bandswitch to the E position (furthest right).
Turn Regeneration fully clockwise.
Set Tuning for maximum capacitance (both sets of plates meshed to left

side

Turn power ON.