Vacuum Tubes Valves
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Vacuum-Tube Valves Circuits
Vacuum-Tube Valves Circuits
The EF50 the tube that helped to win the War
The history of a pioneering tube that was developed by Philips Research and that was, next to the magnetron, The most important tube from World War II The radio valve factory of Philips in Eindhoven was the scene of unusual tension and activity in the evening of the 9th of May 1940. The Germans had been building up an enormous armed force near
Tube in a Tube Clock
The clock described on this page is the result of both events, a simple single digit nixie clock with some interesting features, but without any difficult components. This clock first of all demonstrates that it is possible to use standard, low-voltage, general puspose, small-signal transistors like the BC550, as nixie drivers. Since I can...
A E1T Decade Scaler Tube raised from the dead
The E1T tube you see on the left has been "in the family" for as long as I can remember. Probably my father took it home from work (he worked at the Shell laboratory in Rotterdam) or he bought it in one of the surplus shops in Rotterdam my father and I used to visit every Saturday morning when I was a child. Because it was such a strange and funny
The uTracer V3 a miniature Tube Curve Tracer
In an instrument like the uTracer, which handles voltages of several hundreds of Volts at currents of several hundreds of mA, it is obvious that an error or malfunction can easily result in the destruction of (a part of) the circuit, especially so since the uTracer is build up from sensitive semiconductors. I vividly recall how a malfunctioning...
Tube Tester for any budget
35 Watts Vacuum Tube Power Amplifier by E80CC and EL34
The circuit was designed to create a power amplifier circuit that will utilize E80CC and EL34 vacuum tubes for better results while providing 35 Watts of..
Line Preamplifier Circuit with Tube Acquisition
The circuit was designed to create a line preamplifier by acquiring the use of double triode tubes. The circuit comprises of three parts, the main preampl..
Three ECC83-Based Tube Phono Preamplifier Circuits
The three circuits were based on the vacuum tube ECC83 designed to produce phono preamplifiers in compliance with the RIAA standards. Recording Industry A..
studio ring flash xenon tubes
MOC3020M Integrated Circuit. I would love a LED to tell me when each cap is charged but I have no idea how to do that or where to put in the circuit, I have a bucket load of 5v LEDs so making use of some would be great. I have Circuit maker but dont have a spice for a xenon and cant find one anywhere so cant virtually test this circuit so its...
6V6 6J5 Class A Vacuum Tube (Valve) Amplifier Circuit
This is my first successful vacuum tube project. The output of this small amplifier in which a 6V6GT output pentode is connected as triode is about 4. 5 watts. This project involves a single ended audio amplifier, which consists of a resistive input network, a driver stage, and an output stage to a typical 8 ohm loudspeaker load, all the while, usi
Fluorescent Tube Light Circuit
Fluorescent Tube Light Circuit of an inverter that uses a single transistor and a single transformer. This type inverter can be made in various..
Vacuum Tube Synthesizers
Lately The Peasant has been building a music synthesizer using vacuum tubes. Although this will be used as a percussion synthesizer, it could just as easily be controlled by a keyboard or a MIDI to CV convertor. The first module built is a dual VCO. It is based on the VCO circuit from Eric Barbour`s Phattytron, and has its own power supplies buil
Valve (tube) amplifier schematic
I don`t believe it was ever intended to be powered off a 9V battery. They`re feeble! Under 2 hours with an Alkaline, or..
Variable power supply for supplying valve amp build
The voltage requirement the Solidus is desirous of is quite a bit higher than your circuit provides I know Chris. It was..
Two Tube AM Transmitter
I finally completed a working AM transmitter. The transmitter`s design is based on several ideas, but mainly based on Phil`s Li`l 7 Transmitter design. It is not always easy to achieve oscillation in LC-based transmitters without the right combination of tubes and coils. The tubes used in this transmitter is a 6J5 and 6SA7 th
Small Vacuum Tube Tesla Coil 2
This tube tesla coil was built inside a CPU power supply unit. It was first built on a workbench using components and jumpers for connections. The tube used is a 4X150 transmitting tube that used forced air cooling. An old oscilloscope transformer was used for the power supply, providing about 1kV for high voltage and 6. 3VAC for the filament suppl
gray tube replication
Gray Tube Replication 50
Originally Posted by Electrotek so is something missing or not? This is what I`m trying to find out. I think you are missing some of the external..
Gray Tube Replication 51
Nice work Spokane & Ghst, i will be in the near future joining you in this replication as this thread is quickly becoming a classic. keep up the..
Gray Tube Replication 6
Has any one tried colliding two High Voltage potentials in a Grey Tube? Wiring two (identical)..
Gray Tube Replication 74
Geotron, I`ve fried a few mots myself. What kind of bridge do you have leaving it? When I had just a 1kv bridge made from four 6a100`s, I had problems ..
Gray Tube Replication 75
Using an odd mix of high voltage diodes although I have some 1200 volt, 6 amp diodes on order which will replace the three HV diodes I`m currently using. The Relay is triggered with a basic transistor circuit and square wave generator. The circu
Gray Tube Replication 85
Originally Posted by kalena555 Dear Mark, The bit of info of getting the motor to run without the tubes is new info to me. So much learn XD. Well now..
Gray Tube Replication 91
Originally Posted by Spokane1 I have just about all of the parts needed for a first run. Mr. Dollard says he used Teflon coated coax, which is..
MDB Ventures Vacuum Tube
This file contains information on tube transconductance. How it is computed and how it is used. It is one of the best descriptions around. It is simple and doesn`t get very deep into the math. It is an old 1940s Bell Labs document written by T. Slonczewski. This file contains information on tube measurements, including mutual conductance, grid vol
wiring vacuum diagrams
The Technology of the Tube Screamer
The Tube Screamer series of distortion/overdrive boxes from Ibanez has a reputation that has led them to pass into musical urban myth. Helped along with Stevie Ray`s use of them, the TS 808 and TS 9 have been sought after and traded up to astronomical prices. The other members of the TS family, the TS-10, the TS-5 and the TS-9 reissue have had a m
Driving a fluorescent tube
Even if a fluorescent tube it`s not a neon glow lamp and this page it`s not maybe at the right place, this circuit is very interesting because it uses an odd way to power a very common lamp. Like glow lamps, neon tubes are composed by two electrodes in a low pressure atmosphere composed by a mixture of gazes; usually argon and mercury producing UV
6N7 Tube QRP Power Amplifier
A Super-Duper Powerful Vacuum Tube QRP amplifier for my 800mW QRPP homebrew telegraph vacuum tube transceiver "3T" (I promise to write a separate article or two about this three tube transceiver project later). It was not an easy decision to me because for that legendary time I`d almost a year used the QRPP power of less than a watt, but there...
Transmitter FM 45W with valve
Audio Filters Circuits
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Musical & Effects Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
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UNBOXED: Reviewing the Solis SO-8000 Vacuum Tube Amplifier
Sep 28, 2017
RS Components – High-reliability and low-power vacuum tube technology delivering excellent sound reproduction ...
Oct 4, 2017
Herb's Denver Day Two, Part Two
Oct 12, 2017
Archives builds Magnavox collection
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Nagra's Heavy-Duty New HDPreamp References the Brand's Past While Looking Ahead
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Jana's Final Rooms at the Denver Show
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JVS Works His Way Up the Marriott Tower
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AuricSound A7 Vacuum Tube Amp XLR Stereo Hybrid
Jul 20, 2017