I'm looking for a simple appliance timer that would turn something on or off in increments of days instead of hours. For instance, it could turn a light off in 34 days or on a specific date.
A countdown time for a single event would work too, I could set it for say 865 hours.
Back in the 'old days' when LED clock kits were common, I made a long term timer by removing the TV color burst crystal most used as a reference and replaced it with one at 1/10 the original crystal frequency. 3.579545 megs IIRC. Ordered a special crystal.
Had to do some playing with the oscillator, but it wasn't any big effort. Lot easier to get them to run more slowly than faster. My accuracy wasn't tremendous, maybe +/- 15 minutes a day, but for my purposes it was fine.
The end result was a clock which ran in 240 hour cycles instead of 24 hour. The clock had an alarm. I took the piezo alarm, toggled a relay, and used it.
I imagine you could do the same thing now if you find enough clocks to look at to where you see one you'd be comfortable modifying.
Regards ..... Steve
********************************************************************* Steve Uhrig, SWS Security, Maryland (USA) Mfrs of electronic surveillance equip mailto: snipped-for-privacy@swssec.com website
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+1+410-879-4035, fax +1+410-836-1190 "In God we trust, all others we monitor"
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Altronix makes decent multi-day timers. Their AT4 model is a bit pricey and it may be more than you need. Following my sig is a link to it on my website.
In this instance, the OP would be better served with an alarm control panel capable of scheduling and interfacing with appliance modules like X-10... The Altronix unit is excellent but the couple of government buildings we service where it's installed are a PITA because you can't download changes. You have to be "on site" to program new times and special holidays. The clock isn't the most accurate either and requires a couple of visits to "tweek" every year. Robert's prices are competitive and the one thing I've observed is he'll adjust them (or match a competitors) when required. A number of online stores will even "dicker" with you on the price if you're placing a large enough order. Always be careful when comparing prices and product. For instance, you can also order just the board (without the fancy enclosure and stand-by battery) which might account for the rather large price discrepancy you've mentioned here.
I sincerely hope no one is actually seriously contemplating purchasing product from any online store recommended by "Satan". Sorry Group (and particularly Mssrs. Green and Kearney)... I just couldn't resist this last bit!! ;-))
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