making tesla coil and energizing tube

This LC meter circuit is capable of measuring inductors and capacitors. When either Lx or Cx is connected to the circuit, the oscillator frequency decreases, and this reduction is measured by a frequency-voltage converter constructed with transistors T3 and...

1000 m single-tube FM transmitter circuit diagram of oscillation. The circuit diagram for a 1000 m single-tube FM transmitter is designed to generate frequency modulation signals suitable for transmission over a distance of approximately 1000 meters. This transmitter employs...

This circuit is designed to demonstrate high-frequency high voltage, capable of producing voltages up to approximately 30 kV, depending on the transformer used. It is economical and straightforward to construct, primarily utilizing a standard TV flyback transformer. The circuit...

To get a low output impedance I needed to use quite a high step-down ratio (20:1); after all, the amplifier may be used with headphones of lower impedance than the 300 Ohms of the HD600. The output valve is...

This review highlights a dual-test scenario involving the FVP preamp, with initial contacts made with Vacuum State and insights provided by Geoff during a trip to Brittany. The FVP was sent to France for evaluation. Geoff tested the FVP5A...

This is a 7-tube, 20-watt amplifier that must be used in conjunction with a preamplifier featuring volume and tone controls. A suitable recommendation is a 6-tube preamplifier. This amplifier utilizes 6BQ5 output tubes and employs a 5U4-G rectifier to...