Christoph Petermann DF9CY 2008

Last Revision: 11 April 2008

Overview

Here is my 24 GHz Transverter, which has been built by friend Dieter, DK1UV, in 1994. He achieved remarkable distances with it on the 24 GHz radio band. Output is estimated to be around 25 mW fed via waveguide into a 25 cm precision dish antenna. Two GaAs Fet amplifiers are used to enhance the signal when transmitting. The same amplifiers are used for receiving. A waveguide switch reverses the amplifier direction. Up/Down mixing is done by a diode mixer. I changed the quartz crystal for to move the operating range from 24,192 GHz to 24,048 GHz. (A 23,904 GHz source derived from a 124,5 MHz crystal [*192] is needed for an IF of 144 MHz.)

Some amateurs around here in Northern Germany are QRV on 24 GHz. So I hope to make a number of contacts in the future.

Images of the 24 GHz transverter


Front View of the 24 GHz transverter


The modules of the transverter


Electrically controlled waveguide switch


The 12 GHz oscillator connected to the spectrum analyser.


Local oscillator spectrum at 11.952 GHz after changing the crystal. Output power is at 13 dBm (=20mW) now.