| Last month we examined the basic theory of loop antennas, and demonstrated some of the basic forms of loop antenna, resonating methods and...
All items tagged with Theory and Construction (17)
| Although it is bound to be replaced within a foreseeable period by environmentally safer types, the nickel-cadmium (NiCd) battery is still...
| The circuit presented here is a dual thermometer that indicates the difference between the temperature indoors and out of doors with the a...
| To achieve a comfortable room temperature quickly it is often required to switch on the central heating (CH) boller tor ten minutes or...
| BUILD THE OPTICALOCK
| Combination locks are useful because they can not be picked like a 'key' lock can. If a combination lock could sound an alarm before it wa...
| This month we present an experimental circuit to demonstrate that visible light can be modulated and used as a carrier to convey informati...
| Those of you who have ever spent a summer's day at the beach will affirm that the sun, the wind, the sand and the water can have a repo...
| This month we tackle a high-frequency project by venturing out into the exciting world of VHF radio amateur communication. Build this conv...
| The test instrument presented here is capable of supplying sine-wave, square-wave and triangular-wave signals with an adjustable amplitude...