Home made.

Click on the picture for enlarge.

De DSW-80 is een QRP CW zend ontvanger voor de 80meter band.


Click on the picture for enlarge.

The "hatch" A Transformerless 10 Watt AM Transmitter for 80 meters.

Made in old cb box.


Click on the picture for enlarge.

70MHZ 150 Watt RF PA.

Made in old cb box.


Click on the picture for enlarge.

Morse decoder.


The Timber TX. 80 M. QRP CW zender.


Click on the picture for enlarge.

 80 MTR Foxhunter receiver.


Click on the picture for enlarge.

Antenne tuning (S match) PA0FRI.


Antenna current meter.

Antenna current meter.


Click on the picture for enlarge.

500 KHz transmitter, now works at 474 KHz


Antenna for 475 Khz. 630 meter. Variable Inductor

Antenna for 475 Khz. 630 meter.   15 meters high and variometer.

        Wound on 31 cm-diameter pipe.                                                                       0.474 MHz SWR

        Variometer 700 to 950 uH.                                                                    

                                              Click on the picture above for enlarge.


How to build a variometer.  Variable Inductor

How to build a variometer.

 

A variometer is easy to build with readily available materials. Two plastic pipes of different diameters, insulated copper wire and a plastic rod for the shaft are the main components.

The figure shows the cross section and the way the coils are connected together.


Click on the picture above for enlarge.

6 en 10 meter Duplexer.

Made for WSPR, for used with band hopping.


Duplexer 70 MHz / 50 MHz.  4 en 6 meter Duplexer
4 en 6 meter Duplexer  70 MHz and 50 MHz

Duplexer 70 / 50 MHz.

Made for WSPR, for used with band hopping.


low pass filter 144 MHz
lowpass filter 145MHz