The solid-state, unity-gain power buffer is easy to imagine, as many already exist. But what about corresponding tube equivalents Have they been made Could one be made Actually, super cathode followers (complex-and-augmented cathode followers with a gain of 0. 99) have a long history, with many interesting designs appearing in the 1940s and 1950
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s. But a tube power buffer robust enough to drive directly loudspeakers is rare, and with good reason: the impedance mismatch can only be easily addressed with an output transformer. Because of the transformer`s phase shifts, however, the amount of feedback that can be wrapped around a tube amplifier and its output is limited. And all buffers use some form of feedback to deliver low distortion and output impedance. Couldn`t an OTL tube-based power buffer be created that would allow much greater amounts of feedback to be used Sure; but it, like all tube OTL amplifiers, will be a beast. In the schematic above, we see a power pentode configured in a simple single-ended topology, with the only interesting twist being the pentode`s cathode direct connection to the transformer`s secondary. This connection eliminates the pentode functioning as an amplifier, as the cathode follows the grid, thus providing 100% degenerative feedback. This short feedback loop gives the pentode`s output stage a low impedance output that it would otherwise be altogether lacking. It also lowers the distortion, improves the PSRR, and extends the bandwidth. Actually, the PSRR is fairly good in a pentode-based single ended amplifier, even without the feedback loop, as the pentode`s high rp, unlike the triode`s low rp, makes a poor voltage divider against the output transformer`s primary impedance. In the schematic below, we can see the noise relationships...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
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....
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....
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....
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....
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,....
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....
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....
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.....
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