Mutchus

Used tubes – 12AX7 [pre-amplifier, tone control and audio pre-amplifier] – 6L6GC [audio output] Circuit diagram Tube pin-out -6L6 Tube pin-out 12AX7

Weston (M.I) Type Frequency Meter Principle:  It is a moving iron instrument which operates on the principle of variation of impedance in an inductive circuit with variation of frequency. Weston Frequency Meter Construction: It consists of two coils A and B mounted perpendicular to each other. Each coil is divided into two sections. The connections are as shown in the above fig. The branch of coil has a resistance R 1 connected in the series with it while coil B has a reactance coil L 2 in series with it. Circuit of coil A is in parallel with a reactance coil L 1 while that coil B is in parallel with a resistance R 2 . The moving element is a soft iron needle. The needle is pivoted on a spindle which is also carries a pointer and damping vanes. There is no controlling torque. The series reactance L 0 acts to suppress higher harmonics in the current of instrument and therefore tends to minimize the waveform errors in its indication. Working: When the meter is connected across th...

Dynamometer Type Instrument ElectroDynamometer Instrument The electrodynamometer type instrument is a transfer instrument. A transfer instrument is one which is calibrated with a D.C source and used without any modifications for A.C measurements. Such a transfer instruments has same accuracy for A.C and D.C measurements. The electro-dynamometer type instruments are often used in accurate A.C voltmeters and ammeters, not only at the power line frequency but also in the lower audio frequency range with some little modifications, it can be used as a wattmeter for the power measurements. Principle: Electro-dynamometer type instruments are very similar to PMMC type instrument in which the operating field is produced, not by a permanent magnet but by another fixed coil (usually two fixed air cored coils are used). The PMMC instrument cannot be used on A.C currents or voltages. If A.C supply is given to these instruments, an alternating torque will be developed. Due to moment of inertia of th...

Valve and Transistor - Grundig Black and White TV - 1962 model - Grundic Eleganz 2300SE CIRCUIT DIAGRAM   I know; nobody will have this model set (working) now.  Yet, publish this post to compare its assembly and schematic with modern Televisions.  Even though it is B/W TV, weigh about 45 kilograms.