Guitar preamp circuit based on JFET 2N5457.
Overall gain is 3db (2X) or so. It uses about 1/2 ma, so a 9V battery will last a long time, you may also use simple regulated power supply with LM7809. It is possible to add a high boost switch in case you like by having it shunt the 2.2k ohm resistor with a 0.05uF cap (or other value; smaller cap = boosts only higher frequencies, as well as the reverse). You may simply placed in a 10uF capacitor across the 2.2k ohm resistor in order to up the gain
In the electrical sector, a schematic diagram is usually used to describe the design or model of equipment. Schematic diagrams are usually utilized for the maintenance and repair of electronic and electromechanical devices / units. Original schematics were made by hand, using standardized templates or pre-printed adhesive symbols, but nowadays Electrical CAD computer software is often used.
In electronic design automation, until the 1980s schematics were virtually the only formal representation for circuits. More lately, using the progress of computer system technology, other representations were introduced and specialized computer languages were developed, because with the explosive development of the complexity of electronic circuits, classic schematics are getting less practical. As an example, hardware description languages are indispensable for contemporary digital circuit design.