Devoted to analog audio, tube amplifier, loudspeaker, radio amateur antenna


The list below contain various articles on radiamateur issues.
It will be frequently updated.

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I will then respond to you as soon as possible. By contacting me, you shall agree, that your question and my answer will be brought in a FAQ on this homepage.

80 m antenna

Here is a description of my 80 m amateur antenna. It is a full size dipol requiering only a limited space. This is due to folding of the legs to an angle of 105 degree in the horisontal plane.

The legs are each app. 19,75 m, giving resonance at 3700 KHz. The feeder is 50 ohm URM43 (RG58), length is chosen as half a wavelength. The shortning facto for the cable is 0.66. Half a wavelength is: (300/3700)x0.66=26.76 m. By using a feeder of half a wavelength you...



Designing the analog power supply.PDF

This article describes how to design an analog power supply, Transformer data is consideret, Charging capacitor, diode rating.  Here you can calculate the resulting DC voltage under load.
Designing the analog power supply.PDF