Tube Mic Pre-Amp circuit electronic.
The 12VAC needed for pin 5 of the 12AX7 can be obtained from point G while pin 4 should be connected to point A.
There are two options for line level signals. First if you know that you”ll be using line level signals all the time with the TMP then you can change the two 33k 1% resistors to 1k 1% types and your done. Alternatively if you want the option of line level or low level signals then you can sacrifice the polarity switch and and rewire it here as shown. Notice that the 47k resistors are again of the 1% variety.
This schematic diagram come from circuit: Tube Mic Pre-Amp
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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.