Johnson's Techworld

That is the wonder of odd harmonic resonance. 6m or 50 MHz band is roughly the 7th harmonic of 7MHz or 40m band. That is an odd harmonic,

We have just gone through a severe (G4) geomagnetic storm as a result of a solar flare which had occurred on 9th November 2025. There was a G5

C-rate is a measure of the rate at which the battery is to be charged or discharged relative to its capacity. The C-rate is defined as the charge

Large loop antennas use a full wavelength of wire while small magnetic loop antennas use a high voltage tuning capacitor and a small coupling coil. Multi-turn loop antennas

Here is the second session on basic antennas for radio communication. This time we are discussing a folded dipole antenna along with something about common mode current, common

White balance in a camera adjusts the colours in a photo so that white objects appear neutral white under different lighting conditions. It compensates for the changes with

Simple way to protect eyes while testing LED tube light!

Know the inner structure of an LED tube light

Which was the simplest VHF antenna I ever made?

Radio needs an antenna for communication with other radios. Simple and easy to construct antenna is a half-wave dipole antenna. It can be mounted horizontally or as in