OT: Need to make a timer....

[10K Pete]

I figured this was as good a place as any, so here goes:

I want a timer for intervals up to, say, 5 or 6 minutes. I want to be able to
set it for an interval. Then I want to set it going and at the end of the interval
have it beep a couple, three times and shut off.

I want the interval setting to stay at what ever I set, not have it zero out and have to be re-set each time. I just want to be able to set it once and hit the button each time I use it. Of course the interval has to be changeable easily,
in seconds graduations. It can have a digital display I suppose. Must be battery operated, a single AA preferred. And of course the battery must
last years!!

This timer will be used for tea and coffee brewing. I'll package it to sit on
the counter. With the timed interval pre-set I can just hit the button and the
thing will beep after the time! Hopefully.....

So I'm not at all conversant in electronics design, but I can build such a circuit,
from a design.

I've searched high and low for a few months and failed to find anything meeting
my needs.

Can anyone help me by providing a, hopefully, simple design for this?
I could make a pcb if necessary but would prefer perf board type build.

Thanks for any assistance,
Pete

 

[Buchanan]

What about one of these?http://www.ebay.com.au/itm/5-12-24V...0267de0&pid=100005&rk=4&rkt=4&sd=191839501408

all you need to add is a buzzer and run it on a 9V battery,

I like the idea

 

[Herbiev]

If you google the old 555 chip you will find something suitable

 

[GailInNM]

Pete,
This timer mayl meet your needs. For several years I have had one of these in the shop that I use almost daily. Mine is a different color but other than that I think they are the same.
Using the MIN & SEC buttons you can preset a count down time. When you touch the Start/Stop button it counts down to zero and the alarm sounds. If you don't do anything the alarm beeps for 60 seconds then the timer resets to the preset value. You can stop the alarm by pressing the Start/Stop and the timer will reset to the preset value ready to go again.

The only thing I don't like about it is the buttons are very sensitive to the touch so it is easy to brush against them and screw up your settings. I put a 1/32 inch thick plastic bezel around the buttons and that prevents that problem. I think it meets your specs except the beeping goes on for a minute if you don't hit the Start/Stop button.
Gail in NM

http://www.ebay.com/itm/112001944845?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[Cogsy]

I immediately thought of a simple kitchen timer like this one for $2.79 and free shipping : http://www.ebay.com/itm/Kitchen-Clo...01944845&tpos=top&ttype=price&talgo=undefined

At least it has all the workings you want and you could make your own housing to whatever design you like. In fact you've got me thinking about getting one myself and custom making something nice for my better half - maybe a steam-punk appearing device...hmmm...

 

[10K Pete]

Thanks guys! The solution was right under my nose in the lowly kitchen
timer like Gail linked to.

I never cottoned to the fact that they would keep the set time, at least some
of them anyway, and would serve the purpose. I've never really 'played' with
one, see?

I did Google the 555 and found a couple of circuits that were very close to
meeting needs, and would, with minor additions.

I looked a the ones on eBay and added a couple to my watch list (including the
ones Cogsy and Gail found) so there are plenty to choose from.

But I'm off to the kitchen to see what is there as I seem to recall some sort
of electronic timer residing there in the past.....

Thanks again,
Pete

 

[GLCarlson]

If you google the old 555 chip you will find something suitable

True. But- you'll put a lot of work into it. Parts, board, a bit of design. Kitchen timer is best/cheapest.

 

[10K Pete]

A safari through the kitchen yielded an electronic timer that hasn't been used
in a decade. Replaced the battery and it works. The function isn't as straight
forward as I'd like but I'll play with it. And, if it irks me too much I'll get one
of the ones linked to on eBay.

Right under my nose the whole time......l:wall:

Pete

 

[10K Pete]

True. But- you'll put a lot of work into it. Parts, board, a bit of design. Kitchen timer is best/cheapest.

I was looking at some of the circuits on line and a couple of very simple
ones are about 90% of what would be my ideal. I may, in my spare time ,
look into making the 'perfect' brew timer. Unless one of the off-the-shelf
models really suits perfectly.....

Pete

 

[james_III]

Why not over engineer things and use arduino uno with http://www.ebay.com/itm/1602-LCD-Di...uino-Duemilanove-Blue-Backlight-/172182501848 With relay shield possibilities are endless :hDe:

 

[10K Pete]

But that's the big joker in the deck..... I don't even know what a arduino is!!! I might as well flap my arms a try to fly.

Pete

 

[ShopShoe]

Now that film photography is almost gone, there are lots of darkroom timers out there. Most of them are not battery powered, but you could probably find something you could use. Around here they show up at auctions, garage sales, and thrift stores. Pay attention to the timing interval(s) they have. Some control AC outlets, some have alarms, some have both.

Search for "Darkroom Timer," "Enlarger Timer," "Photo Timer," etc.

--ShopShoe