Sunday, 13 February 2011

QRP antenna tuner circuit


Low power ( 3 to 30 MHz) transmitters constructed by hams are generally called QRP’s. For such transmitters a well tuned antenna is a must.If the impedance is not properly matched there will be a little or no output.But if properly matched there will be great results.A circuit for matching the antenna properly with the transmitter id given below.
The output of the transmitter is given to the input of the tuner( connector BNC1). The output of the tuner(connector BNC2) must be connected to antenna.Then adjust the L1 and C1 to obtain the maximum transmission power.The transmission power can be checked using a SWR meter.

1 comment:

  1. Even though this is rather old now, I noticed that there is either a typo or an error in the schematic.

    In the text it says "adjust the L1 & C1". If you look at the schematic, L1 is not adjustable, only C1 & S1 (for C2 & C3).