Timer Schematic

DIY timing systems
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daveppeters
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Timer Schematic

Post by daveppeters »

Does anyone have a schematic for a four-lane timer? I have the plans from Pack 471 and would like to build a timer based on it, however, I am not sure how to tie in the additional quad comparator. Any help would be appreciated.
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Da Graphite Kid
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Re: Timer Schematic

Post by Da Graphite Kid »

Dave,

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gpraceman
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Re: Timer Schematic

Post by gpraceman »

I went ahead and posted the 4 Lane version of Pack 471's plans on my GrandPrix Race Central site at http://grandprix-race-central.com/modul ... ne_Version. This is the schematic that I made up when building the circuit for my Awana club in San Diego. It corrects a couple of problems with the Pack 471 circuit and adds in LEDs to indicate the status of each lane sensor, the start switch and the power supply. The LEDs make testing the system without a computer hooked up possible.
Randy Lisano
Romans 5:8

Awana Grand Prix and Pinewood Derby racing - Where a child, an adult and a small block of wood combine for a lot of fun and memories.
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mrvoltz
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Re: Timer Schematic

Post by mrvoltz »

I know this is an old thread but I have reworked this circuit and the info you seek is on my site.
You don't need the second comparator if you make some simple changes that I found are more reliable.
Dave Wright
Awana Ministry Team, North and Central Florida
Blue Zone, Grand Prix Specialist
http://awana.wrightmap.com" target="_blank
John Shreffler
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Re: Timer Schematic

Post by John Shreffler »

I can supply the complete schematic for the 4 lane Judge, which was the king of finish lines from 1993 to 1996. It is all gates and flip flops. When the microprocessor came along, this model was discontinued for economic reasons. However, the ability to split hairs is actually superior to anything on the market. The reason is that the lockout feedback loop delay is measured in nanoseconds, not in microsecond clock ticks. Anyone wanting a piece of history, send a SASE. My address is on my web site
--John
www.newdirections.ws
John Shreffler
Maker of The Judge
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