Gysel couplers
The Gysel coupler (under construction) There are many ways in combining amplifiers. Wilkinson dividers, hybrid couplers or rat-race couplers are the best known couplers […]
RF construction
YL1050 1296 MHz amplifier DL9EBL design
A YL1050 amplifier designed by Karl Schötz, DL9EBL. Karl handed me a floppy with the drawings of his amplifier. I printed them and these are […]
70 MHz low pass filter
Low pass filter for 70 MHz In need of a low pass filter for my 70 MHz transverter, I decided to build the filter […]
Conversion to 1296 MHz for the DF1SR circulator
In need for a number of circulator / Isolators for my new 23 cm solid state PA, I got some circulators from Georg DF1SR. These […]
DF1SR hybrid pics and test
If you are looking to combine several amplifiers on 1296, you might be looking for a hybrid coupler. Making one of those is a big […]
Remote antenna switch
As a result of the solid state protection found on this web-page I decided to play with a remote antenna switch which could switch up […]
Wilkinson divider for 145 MHz
For operation on 2320MHz I needed a receive power splitter for my IF 144 MHz. It had to cover the 100-150 MHz range. The first […]
Using the specan as a dipmeter
Using the spectrum analyser as a dipmeter For a long time I never had the need to have a dipmeter for HF and VHF. This […]
HF amplifier 2 x GS31
Below you see some pictures of my HF amplifier. I used some chain gearing to move a pot-meter together with the vacuum caps and the […]
5 pole Cauer filters for the HF bands
To build a solid state amplifier today, one has the availability of many fets. Preferably Ldmos as this is the most sturdy and the most […]