Vectronics VEC-131K - Manual (Page 3)

VEC-131K Owner's Manual Aircraft Receiver Kit
1
INTRODUCTION
Imagine climbing into the cockpit and experiencing first-hand how pilots and air-
traffic controllers work together to keep our skies safe. Open the door to
exciting aviation action; let the VEC-131K be your key to easily intercepting
air-comms 100 or more miles distant! Track the progress of incoming and
outgoing traffic in your area, hear advanced weather information firsthand from
pilot reports (PIREPS), and discover how the National Air Traffic System really
works. The VEC-131K is not only fun to build and operate, it’s also a great way
to learn about radio-electronics and aviation!
When it comes to pulling in weak signals, the VEC-131K rivals many
commercially built aircraft transceivers. Its electronic tuning control covers only
those frequencies used for aviation voice communications--118 to 136 MHz.
The VEC-131K consumes minimal electrical current and can run for hours from
its self-contained 9-volt flat-pack alkaline battery. Plug in a 8-ohm speaker or
use headphones for loud-and-clear reception.
The VEC-131K is a single-conversion Superhet featuring a sensitive LNA front
end and a varactor-tuned oscillator providing frequency coverage from 118 to
136 MHz. Zener diode regulation keeps the frequency control stable, even when
battery voltage is low. A 10.7-MHz ceramic IF filter is also included. Four
modern integrated circuit (IC) devices keep construction simple, on a PC board
measuring a mere 3 x 3.25”. Whether monitoring exchanges between distant
ground stations or strong overhead aircraft, the audio remains level thanks to an
advanced-design Automatic Gain Control (AGC) system.