6 windings together and 8 windings distributed over the core Windings distributed over the core Schematic: First measurement:...

To reduce interference from man-made noise, I often use a loop antenna which is known for its ability to decrease unwanted signals. I...

A pole of 10 meters is used. From the top to the middle (feedpoint) 5 meters of 2.5 mm² is used. From the middle (feedpoint) two radials...

Bottom view: Top view: Schematic diagram Air coils: Wire diameter = 0.8 mm Diameter pen = 9.7 mm L1 = 2 turns L2 = 3 turns L3 = 5...

I built two identical tuners to go from 50 Ohms to a complex impedance and then back to 50 Ohms. This makes it easy to measure the...

It was my friend Eric ONBEW who drew my attention to a number of articles (from G3TXQ, DJ0IP and W7EL), which mentioned that a 1/4...

New version Old version I changed the shape from square to circle. Height and width of the loop are 1 meter. This means that one...

Picture: Upper core = FT240-43 1:1 curent balun Lower core = FT240-43 1:4 Guanella current balun Wires are wound in a different way! Take...

Be careful when removing the core as it is very fragile! 10 windings were made both top and bottom. They behave like 100 ohm transmission...

Height and width of the loop are 1 meter. This means that one turn = 2.80 meters. In this case i have used tree turns = 8.40 meters. New...

Height and width of the loop are 1 meter. This means that one turn = 2.80 meters. In this case i have used two turns = 5.60 meters. I...

The feedpoint Square with a side = 5 meters Hard to see on the picture. top left is the feedpoint Used material: 1 core of 73 material...

Pictures: Schematic: U out = 2.5 x U in ==> Impedance Out = 2.5 x 2.5 = 6.25 x impedance In @ 50 Ohms in, Out = 312 Ohms. Measuring...

Picture: Schematic: Input: 3 transmission lines with an impedance of 150 ohms in parallel = 50 Ohms, Output: 3 transmission lines with an...

Used material: - 3 cores Amidon 240-43 - copper wire 1.8 mm diameter - PTFE tube with 2 mm internal diameter and 3 mm outside diameter -...

Used material: FT240-43 Schematic: Insertion loss: Return loss: Common mode rejection:

Guanella 2 wire Ruthroff 3 wire Schematic: Guanella 2 wire Ruthroff 3 wire Return loss: Guanella 2 wire Ruthroff 3 wire...

Used material: AmidonFT240-43 core. Top view Bottom view This is the way I think it should be made. Schematic: Insertion...

Used material: Amidon FT240-43 cores. LEFT = 2 conductors RIGHT = 4 conductors Left: transmission line with an impedance of 100 ohms....

For building descriptions, see my previous blogs. Return loss measurements: Insertion loss measurements: Insetion loss @ 14 MHz = 0.2 dB...