Boosters are not buffers! While it is possible to make a booster that also provides a buffering action, the vast majority of the boosters commercially available ready-made or kits, do not have the proper design to be buffers. A buffer should have a high input impedance (Z) and a low output impedance. The LPB1, shown at the top of this post, has a
Click here to download the full size of the above Circuit.
fairly low input impedance, which automatically disqualifies it from the buffer category. The mini-booster has a high input impedance but a moderately high output Z, and is not a good buffer either. Another part of these designs that prevents their use as buffers is that they have a volume control potentiometer on the output. The volume pot impacts the impedance of the circuit. If the volume pot is at the 50% position, represented above by R5 and R6, the output pot is acting as a voltage divider. Here we have the 100k pot in parallel with the output impedance of the LPB1 (10k) that is driving the cable to the amp or next pedal. The cable capacitance (Cc) even on a good cable can be 800pF, as I measured in a previous test, and is shown on the schematic in light blue. The output impedance of the booster and the resistance of the pot are driving the cable and form a low pass filter with the cable capacitance. In this example, the high frequencies are rolled off starting at around 7. 2kHz. This is obviously not what we want from a buffer! This is a typical opamp distortion pedal schematic fragment, and the high frequency limit is similar to the transistor booster example (7. 5kHz corner frequency). You should note that as the volume is turned up, the frequency limit rises as well, letting more high frequencies through. The shunt resistance of the pot, shown as R6 on the examples, is in parallel with the input impedance of the...
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.....
characters left: