As shown by the block diagrams in Figure 1, overall signal flow in this five-input mixer was minimally changed upon modification, but I added solid-state buffers that drive independent direct outputs for the five preamp channels. For each channel, the audio signal for the respective op amp-based buffer is taken from the channel fader`s wiper. Thu
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s, channel faders are used to set direct output levels concurrently with relative mix levels in the modified MXM. I designed the channel output buffers to have high impedance inputs (1 M-ohm), which minimally load the preceding tube preamp stages (see below and Figure 10 ). Other changes to the signal path visible by comparing the block diagrams ( Figure 1 ) are: (1) simplification of Channel 1`s input options, and (2) elimination of the original "high-impedance" unbalanced mix output, with use of a solid-state output buffer instead. I present these modifications in greater detail below. As an overall upgrade to the MXM`s signal path, I replaced all of the original coupling capacitors. In most cases I chose Sprague "Orange Drop" polypropylene film units (this is most apparent in Figure 3, bottom), which are famous for their musicality. Originally, Channel 1 had a three-position screwdriver-slotted rotary switch on the front panel to select between microphone, phonograph and auxiliary inputs. As seen in Figure 5, this three-pole (3P3T) switch not only selected the input coupling, but also swapped filters within a feedback network (between 7025 triode stages) to add equalization (EQ) for the phono setting. Passive filter networks at the "magnetic" and "crystal" phono inputs contributed additional EQ for the different 1960s-era phono cartridges. This EQ is obsolete by modern standards, as are monaural phonographs. I therefore...
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....
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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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