This document describes a simple circuit that can be built to receive communications between aircraft and ground control in the 220MHz to 400MHz frequency band. The circuit uses inexpensive common components like resistors, capacitors, an inductor and transistor. It provides an easy and low-cost way for people to listen to air-ground radio conversations given that radios and scanners to receive these frequency bands can be large, complicated and expensive.

1. Airband prijemnik 220MHz to 400MHz band
The communications between commercial aircraft and
the ground can be interesting, amusing and sometimes
even disturbing. However radios that receive the
approximately 220MHz to 400MHz band commonly
used for aircraft (both military and commercial) are not
easily found. And scanners can be complicated, large and
expensive. With an easy to build circuit such as this one,
everyone can enjoy listening in on these conversations.
Part
Total Qty.
Description
Substitutions
R1, R3
2
47K 1/4W Resistor
R2
1
10K 1/4W Resistor
R4
1
4.7K 1/4W Resistor
R5
1
5K Linear Taper Pot
R6
1
2.2K 1/4W Resistor
C1, C2, C3, C6 4
0.001uF Ceramic Disc Capacitor
C4
1
2.2pF Ceramic Disc Capacitor
C5
1
1pF Ceramic Disc Capacitor
C7
1
15uF 15V Electrolytic Capacitor
C8
1
18pF Variable Capacitor
D1
1
1N82 Diode
Q1
1
2N918 NPN Transistor
L1
1
See Notes
L2
1
1.8uH Inductor
ANT1
1
Approx. 18 Inch Wire Antenna
MISC
1
PC Board, Wire, Knob For C8
1. The circuit originally appeared in the Think Tank column of the Sept. 1995 issue of Popular
Electronics.
2. L1 is made by winding 2 turns of 22 AWG magnet wire on a 5/32 drill bit. This inductor can be
modified to shift the frequency range of the circuit.
3. The antenna can also be placed at the anode of D1 if overload is a problem with it connected to the
emitter of Q1
4. R5 adjusts regen and thus sensitivity.