Rongge

Description A digital stop watch built around timer IC LM555 and 4-digit counter IC MM74C926  with multiplexed 7-segment LED display. MM74C926 consists of a 4-digit counter, an internal output latch, npn output sourcing drivers for common cathode, 7-segment display and an internal multiplexing circuitry with four multiplexing outputs. The counter advances on negative edge of the clock. The clock is generated by timer IC LM555. The circuit works off a 5V power supply. It can be easily assembled on a general-purpose PCB. Enclose the circuit in a metal box with provisions for four 7-segment displays, rotary switch S1, start/stop switch S2 and reset switch S3     Testing First, reset the circuit by pressing S3 so that the display shows ‘0000.’ Now open switch S2 for the stop watch to start counting the time. If you want to stop the clock, close S2. Rotary switch S1 is used to select the different time periods at the output of the astable multivibrator (IC1). Digital Timer Cir...

If you have always wanted to have a cool looking timepiece that is extremely difficult to read, then you would not be able to go wrong with Tokyoflash’s collection of timepieces. Their latest addition to the collection would be the $178.99 TokyoFlash Kisai Adjust, where it will boast of a digital triangle time readout. You can opt to tell the time in either a horizontal or vertical display, depending on your cup of tea, and there are also half a dozen LED colors to choose from, with the option for multi-color transition thrown into the mix along as well. Just how does the TokyoFlash Kisai Adjust work? Well, it will be able to show off the time in a non-stop array of changing mosaic of LED triangles. You can opt to have it shown off in either 12 or 24 hour modes, and some might say that the vertical mode makes it easier to read the time compared to the horizontal mode. Even more, when night falls, the Tokyoflash Kisai Adjust would feature a tiny fish that swims across your wrist, accomp...