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On this pages you will find informations about radio equipment that I have developed. Some are available as kit or ready-made unit. You can download data sheets or construction manuals of most of them.

Brand new:

Transverter for the 4 Meter Band

Technical Data:

Frequency range                         Supply voltage

Current Consumption                    Size

Noise figure
Immage rejection

Input power
Output power
Unwanted emissions and harmonics

69.5MHz ... 71.5 MHz 28.5 ... 30.5 MHz
10.5 ... 13.8 V
70mA receive max. 6.5A transmit
160x75x50mm incl. heat sink


1mW ... 8W, configurable
40W (CW), 25Wpep (SSB)
-30dB bei 25Wpep

Foto des Transverters
The transverter is available from stock as kit (185.-€) or as ready-made unit (279.-€).
Here a flyer and the complete manual (currently only in German, English version follows).
If you are interested to obtain one, please send me a mail.


70cm PA with ultra short RX/TX delay for FM and digital modes

Digital operation modes become more and more popular in amateur radio. Here transmission protocols are in use which require extremely short latency times for receive and transmit switching. With TDMA schemes like MOTOBRO or DMR they are below 1 Millisecond. Standard power amplifiers with relays are unusable then.
The P40X amplifier uses pin-diode switches and doesn't have that limitations. It is perfectly suited for modulation schemes with constant envelope like FM, GMSK and C4FM.

Frequency range:   420...450MHz
Output power:       up to 40 W (depending on supply voltage and drive power)
Supply voltage:     11 ... 13,8 V
Input power:        0.4 ... 5 W
RX/TX delay         <100 micro seconds

P40X picture

The little brother of the P40X for USB radios like DV4mini or Openspot

There are an increasing number of UHF tranceiver modules with Milliwatts power in the size of USB sticks or plug-in modules which are controlled by powerfull software running on a PC. Now you can push to power up to a level of 10 Watts with the P8X brick. Also this unit has an extremely fast RX/TX switch.

Frequency range                     420 ... 450 MHz
Output power                         up to 10 W (depending on drive level and supply voltage)
Drive power                           8 to 20 mW
RX/TX delay                          <100 Mikroseconds

Here the manual of the PA.


Now with USB interface and improved RF front-end
Receiver for Weather Satellites with Antenna diversity


There is a new R2F-Config version available. It is working also with Windows 10 and all problems with RS232-USB converters seem to be solved. You can download it here.