Automatic recording telephone interface circuit
Posted on Mar 28, 2007
New Circuits
-
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.....
.
This is not a sophisticated automatic keyer but it is lot QRP to build and to have fun operating...
The usual chargers of battery automotive, are simple and cheap appliances that charge...
Only one out of 9,999 possible codes has the power to unlock this simple, yet effective,...
This circuit charges the battery at 75 mA battery can be left in the charger indefinitely, until...
That hum noise is produced by electronic device with improper design, yes you`re right. And you...
A robot is an automatically guided machine, able to do task on its own. Another common...
The line is purposefully not straight, to see how it would do with zig-zags and splits, as are...
An obstacle avoiding robot is an intelligent device, which can automatically sense and overcome...
The figure below shows a schematic diagram of a simple FM receiver. This receiver made with four...
35W resistive and capacitive half-wave phase-shift trigger doer control circuit Automatic or...
characters left: