I designed and built this Ring Counter Clock in 1970. The base is a 12` diameter/2` thick block of walnut from a hollowed-out gun stock blank. The back side of the base has been hollowed out to hold the circuit board. I chucked it up in a large lath and turned it inside and out. Then I drilled 120 holes for the lights and five holes in the center
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for controls and a time base trimmer. The copper clad board was made by making a drawing board layout on Mylar with tape dots and strips, twice the size of the board. Then a board size photo negative of the art work was used to photo print the board. This clock can maintain time of ±1 sec for months, and has been operating for 41 years, except when it was necessary to replace a bulb and when it was moved from one state to another. I keep thinking I will replace the bulbs with LED`s some day, maybe when I run out of bulbs. Many of you may be too young to know, but in 1970 we did not have microprocessor chips to perform every electronic function known to man. We actually made circuits to perform the functions we needed, without programming. The electronics of the clock consist of a clock circuit made up of a 1MHz crystal oscillator and a TTL divider chain down to a 1Hz pulse. I did not show the clock circuit because there are several more simple ways to arrive at a 1Hz pulse now then how I designed this in 1970. The ring counter circuit shown in the schematic is a modified circuit of one shown in the first edition GE semiconductor data handbook. There are three of these ring counters used in the clock: one 60 section ring for the seconds, one 60 section ring for the minutes and one 12 section ring for the hours. Each of the ring section is designed around a 2N4990 SUS (silicon unilateral switch), I believe this device is...
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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