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- Hours, Minutes and Seconds display - Timebase is a Temperature Compensated Crystal Oscillator (TCXO) - Real Time Clock with Lithium Cell backup of time and all user settings - Simple time setting using two buttons - Programmable leading zero blanking - Five programmable neon colon settings (Flashing AM/PM indication, illuminated AM/PM indication, both flashing, both on, both off) - Maintains time during setup mode, eg. When changing between standard time and daylight savings time - Seconds can be reset to zero to make small adjustments / precisely set the time - Infinitely programmable night time blanking period to save tubes - Separate modes for colon neons during night time blanking - Four display modes: Dim, Bright, Fading digits, Blanked - Ten different possible fade speeds in fading digit mode The kit of electronic parts is fully inclusive The clock kit is fully inclusive, and is a really enjoyable and satisfying project to complete, with a truly beautiful item for your home at the end, to show for all your hard work. It also makes a great gift - either the kit or the fully finished clock mounted in your own design of case. The use of a precision TCXO chip as the timebase gives supreme long-term timekeeping accuracy of +/- 1 minute per year. Every 64 seconds, the TCXO IC measures the temperature of it's in-built quartz crystal oscillator and adjusts the load capacitance to compensate for temperature effects. Ordinary quartz crystals usually keep 20ppm accuracy or special crystals can be found with 10ppm accuracy. However, this is a theoretical accuracy and PCB layout effects can significantly reduce the accuracy. The DS3231 IC integrates crystal, temperature compensation and real-time clock into a single IC to achieve true 2ppm accuracy over a wide use-temperature range of 0C to 40C (32F to 104F) The clock kit is fully inclusive: All electronic components are provided, including: All transistors, resistors, capacitors, ICs, diodes 2 X Neon bulbs for hours:minutes:seconds separators Double sided, plated - through - hole PCB Fully pre-programmed PIC microcontroller, with socket Assembled clock kit, ready for mounting in your own case Finished clock mounted in a case of African Sapele (Not included) The kit is supported by a 22 page fully detailed user instruction guide to assembly. The assembly instructions include many detailed photos, and step - by - step instructions for building, testing and using the clock. The kit uses one surface mount device - the DS3231 TCXO IC as pictured below. The IC is not available in through-hole packaging. The comprehensive instructions explain a simple technique to reliably solder this device. The pitch of the pins is the widest of any surface mount device so soldering in place should be easily within the capabilities of the average electronics hobbyist. Close-up of PCB showing timekeeping components - DS3231 and CR1220 Lithium Cell The two buttons have the following functions: Press and hold 'Set / Blank' button for 2 seconds until the minutes flash. Press the 'Up / Reset Secs' button to set the minutes. Briefly Press 'Set / Blank' again and the hours will flash. Press the 'Up / Reset Secs' button to set the hours. Briefly Press 'Set / Blank' again to revert to normal clock operation. Briefly Press 'Set / Blank' button to toggle between display modes: Dim -> Bright ->Fading ->Blanked From normal clock operation, press and hold 'Up / Reset Secs' button for 2 seconds. Seconds will be set to zero, and held until the button is released. Press and hold 'Set / Blank' button for 4 seconds. Component side of finished clock PCB Clock PCB powered up showing leading digit blanking Clock mounted in a wooden case (not included) (Nixie tube clock kit with in-8-2 nixie tubes included was posted and is owned by: Cheryl Logan) |
C-logan@chicagopartsnetwork.com (Cheryl Logan) for more information.
