Antenna tunning circuit for 27MHz CB band

Posted on May 2, 2012

The antenna tunning circuit can accommodate 1/2 wave length antennas or higher, for input resistances of 50 Ohms which make it suitable for CB (Citizen Band) transceivers. C1 is for fine tunning and C2 is just for tunning. Turning C3 with the help of C2 you can set the SWR to 1:1. The Coil L is made of 11 turns of insulated copper wire with diameter of 1mm.

Antenna tunning circuit for 27MHz CB band - image 1
Click here to download the full size of the above Image.

If you use 1/2 wave length antenna (5.5m) then C3 has to be set to highest capacitance. The connection with the receiver can be done using the SO-239 connector (UHF) or with BNC's. Keep the distance of the cable between the transceiver and the tunning cir

Leave Comment

characters left:

New Circuits



Popular Circuits

Simple Phono Preamplifier
clk3 binary alarm clock
Sensitive electromagnetic field sensor
Solar Panel Optimizing Battery Charger
Dynamic braking circuit control thyristor
Current three-phase motor phase protection circuit diagram