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- Jan 14, 2009
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Hey ,
This was a project I did over the last week . It's based on 3 dual BCD counters , 7 Quad AND gate IC's , One BCD-7 Segment driver and 4 4017 decade counters and a few resistors , LED's and 1N1484 Diodes , Transistors . Supply is 2 5Va transforms at 7 and 9 V and one 1.6Va transformer at 22V
Video of it running can be seen here - https://www.youtube.com/watch?v=JDMBcq2oVBk&list=UUvjDVNxRU2DInDMQQw_iYJA
Timing is done from the mains frequency , 50Hz - 100Hz - 10Hz - 1Hz .
Display is a large VFD driven by 8 ( 1 for grid ) NPN/PNP level shifters at 24 Volts .
AND gates are used along with 16 diodes to select the digit to display with the 4017 doing the timing for when to display time , its currently setup at 48 seconds off and 12 seconds on with it displaying the time twice at 1 second per digit to complete a 60 second cycle .
IMG_0900[1] by TwirlyWhirly555, on Flickr
IMG_0898[1] by TwirlyWhirly555, on Flickr
IMG_0897[1] by TwirlyWhirly555, on Flickr
IMG_0896[1] by TwirlyWhirly555, on Flickr
IMG_0902[1] by TwirlyWhirly555, on Flickr
This was a project I did over the last week . It's based on 3 dual BCD counters , 7 Quad AND gate IC's , One BCD-7 Segment driver and 4 4017 decade counters and a few resistors , LED's and 1N1484 Diodes , Transistors . Supply is 2 5Va transforms at 7 and 9 V and one 1.6Va transformer at 22V
Video of it running can be seen here - https://www.youtube.com/watch?v=JDMBcq2oVBk&list=UUvjDVNxRU2DInDMQQw_iYJA
Timing is done from the mains frequency , 50Hz - 100Hz - 10Hz - 1Hz .
Display is a large VFD driven by 8 ( 1 for grid ) NPN/PNP level shifters at 24 Volts .
AND gates are used along with 16 diodes to select the digit to display with the 4017 doing the timing for when to display time , its currently setup at 48 seconds off and 12 seconds on with it displaying the time twice at 1 second per digit to complete a 60 second cycle .
IMG_0900[1] by TwirlyWhirly555, on Flickr
IMG_0898[1] by TwirlyWhirly555, on Flickr
IMG_0897[1] by TwirlyWhirly555, on Flickr
IMG_0896[1] by TwirlyWhirly555, on Flickr
IMG_0902[1] by TwirlyWhirly555, on Flickr
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