Category: Radioamator i Krótkofalowiec
Eng. Konrad Widelski
All About Electric Guitar - Part I
Radioamator i Krótkofalowiec Polski, Year 17, September 1966, No. 9
Due to the unflagging interest in electric musical instruments, and especially in such a very popular electric guitar - we are publishing the first part of an article written on this subject. The entire study, consisting of three parts, should give interested persons an answer to their doubts.
An electric guitar differs from a normal (mechanical) guitar in that it requires a suitable amplification device for its use. However, before we take a closer look at this apparatus, we will devote some space to the guitar itself. Its principle of operation is by no means complicated. Figure 1 shows a schematic diagram of the so-called magnetoelectric transducer, which is an essential element of the instrument.
Fig. 1. Construction of a magnetoelectric transducer
Such a transducer consists of a permanent magnet and two spools with a winding made of thin insulated wire, mounted near its poles. The whole thing is placed directly under the steel strings of the instrument. During play, the string set in motion changes its distance from the front part of the magnet. This, in turn, causes changes in the magnetic flux in the system and the induction of electromotive forces in the winding. The electrical voltages produced by the transducer most closely correspond to the vibrations of the string, and thus to the sounds it produces. These voltages should then be suitably amplified and reproduced through the loudspeaker.
The mechanical vibrations of the air generated by the loudspeakers perceive listeners as sound impressions. A block diagram of this type of electroacoustic set is shown in Figure 2.
Fig. 2. Block diagram of the electroacoustic set
You can also use an existing standard mechanical guitar as an electric guitar. For this purpose, a magnetoelectric transducer should be mounted to it. Such transducers are factory-produced and sold in music stores for about PLN 100.
The transducer/pickup can be easily attached to your guitar, following the instructions given in the pickup's factory manual.
Making the transducer yourself, although it is also possible, should probably not be an option, because it is a task (especially in relation to the mechanical part) that is too difficult to do at home.
Read more: All About Electric Guitar - Part I.