Home made.

Click on the picture for enlarge. And for more info.

The DSW-80 is a QRP CW transceiver for the 80 meter band.

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

Made in old cb box.


70MHZ 150 Watt RF PA.

Made in old cb box.


Click on the picture for enlarge and info.

Morse code decoder.


Morse code pen writer.


The Timber TX. 80 M. QRP CW zender.


 80 MTR Foxhunter receiver.


Antenna tuning (S match) PA0FRI. Antenna current meter.


Lightning protection and equipotential bonding.


Protection transformer. (Beschermingstransformator / scheidingstrafo)


GW3UEP  500 kHz transmitter.  Now works at 472 / 479 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.                                                          

                                             


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.


Power supply one 24 volts and one 26 volts 15 ampere, and a 13.8 volt 35 ampere.


Click on the picture for enlarge.

6 en 10 meter Duplexer.

Made for WSPR, for used with band hopping.


Duplexer 70 / 50 MHz.

Made for WSPR, for used with band hopping.


low pass filter 144 MHz
lowpass filter 145MHz

Please note: the images on these sites show my own Morse keys and devices.

They may only be used for private purposes with reference to my site. (Source reference)