Vacuum Tubes Valves
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Vacuum-Tube Valves Circuits
Vacuum-Tube Valves Circuits
Stereo Tube Amplifier
The circuit is simple, yet is capable of excellent performance. I designed it specifically for use as an amplifier for the digital sound card in my computer. Audio input can be from any two-channel line level device such as a television, CD player, or VCR. It is of the tube type, using only 5 tubes total with no more than about 45 Watts power cons
Stereo Tube Amplifier circuit
The circuit is simple, yet is capable of excellent performance. I designed it specifically for use as an amplifier for the digital sound card in my computer. Audio input can be from any two-channel line level device such as a television, CD player, or VCR. It is of the tube type, using only 5 tubes total with no more than about 45 Watts power...
Tube Power Amplifier with EL34 - 35W circuit
It`s a classic designing of final amplifier 35 W, with two EL34 in push-pull, from the Siemens and Halske, with year of designing 24/3/1953 and code SV410/1. The amplifier it worked from 1954 until 1989, whenever it came also out except operation, with mean of operation 15 hours per day..
Tube power amplifier 5W with EL84 circuit
Vacuum Tube Circuits
Three ECC83 Based Tube Phono Preamplifier Circuits
circuit for 12AU7 tube distortion
I am attempting to build a distortion circuit using 1 12AU7 tube as a diode. I know that the circuit is primitive but really its only to add in the ex..
Stereo Tube Amp
Vacuum Tube Tesla Coil (VTTC
Here is the particular schematic for the Tesla Coil that we will be building. I do not take credit for its creation - it was made by Steve Ward and yo..
Tube tester collection
This is an experimental tube, that never made it. It was made by one of the Engineers of EI in Serbia, just out of interest. It was an idea of Mike Matthews from new sensor, and the tube was based on the PL519, and had indeed the characteristics of a 300B, and full 40 Watt. So it`s not the history of the 300B, but almost. The tube was to
The meter has only one scale (0. 150) but this also used for 0. 75 and 0. 30. This is such a pain, and all people use a calculator with it. I made a new meter scale for it, with all ranges. This improves the comfort so much New Meter Scale for your L3-3! Due to many requests, this new meter scale is for sale. This is on an opaque sticker foil....
The diode tube we are about to study is really Edison`s old incandescent bulb with the plate in it. Diode means two elements or two electrodes, and refers to the two parts within the glass container that make up the tube. Within a few years after the discovery of the Edison effect, scientists had learned a great deal more than Edison knew at the t
Vacuum tube audio amplifier
Where can you obtain a 12AX7 tube, you ask These tubes are very popular for use in the "preamplifier" stages of many professional electric guitar amplifiers. Go to any good music store and you will find them available for a modest price ($12 US or less). A Russian manufacturer named Sovtek makes these tubes new, so you need not rely on
4 Watt Single Ended Vacuum Tube Amplifier
Flea Power Vacuum Tube Amplifier
US-Army I-177-B Mutual Conductance Vacuum Tube Tester
Custom Webcor Music Man Two Channel Stereo Single Ended Class A Tube Amplifier with Preamp Outputs
nixie tube clock circuit
The nixie tube clock consists of a high voltage power supply, seven rings counters and an Atmel AVR processor. The power supply is shown in schematic Schematic 1. It takes 12 volts AC and converts it to DC which drives the Maxim 1771 switching power supply to generate 160 volts. The Maxim 1771 operates by effectively shorting the 12 volts DC to
Improved vacuum tube models for SPICE
As my principal hobby interest is now photography and I work crazy long hours at Imatest, I won`t have much time to update this article or answer difficult questions. James E. Lanier`s PSPICE Triode Calculator is a promising program for finding tube model parameters. It`s still under development; he plans to expand it to include tetrodes and pent
A discussion of the Williamson Amplifier should be first preceded by an overview of its context in the evolution of the vacuum tube and its application to high fidelity audio reproduction. Transformer coupling was widely used pre-war because it was simple and effective. It was widely used throughout WWII and later - particularly for public...
valve amp circuit
5 Tube AC/DC Radio Receiver
Virtually all AM radio manufacturers used this exact circuit from about 1948 to 1963 or so. People are starting to collect these radios as antiques of sorts. I would be happy to credit the creator of this figure and caption, but I don`t recall from where I down-loaded this. If you made it or know who did, please give me an electronic holler.
Vacuum tube tesla coil (VTTC) using Russian GI-30
A nice and compact setup, that works off-line, directly at 220V, with only a voltage doubler to get the plate voltage up to 560V DC. I don`t need to go into details explaining this circuit, it is a simple Armstrong oscillator, using the feedback coil L4. Here is a great tutorial detailing all the basic knowledge and know-hows behind a VTTC. My...
Vacuum tube tesla coil (VTTC) using Russian GU-81m
The coil has been added a few extra turns, so I had to find a way to improve the insulation. I opted for epoxy, with some extra quantity added over the soldering:
Miniature Vacuum Tube Tesla Coil
Vacuum tube tesla coils operate in a continuous wave mode of operation, continuously providing energy to the tesla coil secondary. As a result, the output is primarily determined by how much power the vacuum tube can process. The spark discharge and operation of these coils is quite different from disruptive coils. If a D. C. voltage is used to...
A Journey into Building Radio Transmitters with Vacuum Tubes
A copy from an old italian magazine of amatorial electronics, proposing an add-on for tube receivers. The add-on was a simple one-tube short-wave transmitter leveraging the same power supply already available in the receiver. This circuit fascinated me when I was just a teenager. I was quite a nerd when I was a teenager. Sure, besides being very c
Battery Powered Tube Regenerative Receiver
Basic Regen design is pretty common, so BEFORE the schematic comes the "concept stage", the "what`s available in the junkbox stage", back to the "concept stage", followed by the "mechanical/electrical layout stage", then sketch a rough schematic. and do it all over again. The BC-221 has always impressed me as having about the simplest, smoothest,
Vacuum Fluorescent Device Regenerative Receiver
This little project arose from a desire to experiment with some of the more "traditional" methods of radioconstruction which enjoyed popularity some 70 years ago. I wanted to find out for myself what kind of performance could be achieved using simple circuits incorporating Valves/Vacuum Tubes and low budget design techniques popular in the 1930`s.
Valve oscillator circuit 100 Metres and Below
The congestion of the ether is becoming so great that efforts are continually being made to extend the channels of communication to higher frequencies. Wavelengths as low as 12 metres are now commonplace, but attempts to work below this are fraught with many difficulties. At about one metre the period of oscillation is comparable with the time tha
valve radio circuits schematics
Build a library of circuits and service data for old valve and transistor radios. There are many available on the internet, but at a price. I would rather share my circuits and manuals with others than try to make money out of them. Thanks to all those who have contributed by sending in manuals. Please, keep them coming. Mullard form
VCM 163 Valve Characteristic Meter Equipment
The AVO VCM 163 is one of the few tube testers (British: valve tester) being able to measure tube electrode currents, e. g. plate and screen current (fig. 1, left-hand meter movement) as well as mutual conductance (fig. 1, right-hand meter movement) simultaneously. The VCM 163 is the latest and most elaborate tube tester ever built by AVO. All volt
Tube 3TF7 Current Regulator
Here are design data for a 3TF7 replacement. Design was based upon the information found in The Ballast Tube Handbook` by Jacobi and on the descriptive field of the R-390x part list: Actually, according to the voltage charts of R-390x receivers, the 3TF7 gives approximately 12 Vac at its output, with an input voltage around 26 Vac.
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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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