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how long will it take untill my battery dies?

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Impossible to tell without knowing more.

You can reduce the power consumption of the timer by using the CMOS version powered from a (larger) 3V battery. You dont need the SSR, just wire the greeting card between pin 3 and the positive pole of the battery.
 
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The datasheet for a 555 timer shows its supply current is from 6mA to 12mA or an average current of 9mA when its supply is 9V.
The datasheet of an Energizer 9V alkaline battery shows its voltage dropping to 6V in 60 hours when it has a load of only 10mA.
A Cmos 555 has an average supply current of 0.12mA (almost nothing) so a 9V alkaline battery will last about 7 months.

The 3V battery is doing hard work so it won't last long unless it is pretty big.
 
The datasheet for a 555 timer shows its supply current is from 6mA to 12mA or an average current of 9mA when its supply is 9V.
The datasheet of an Energizer 9V alkaline battery shows its voltage dropping to 6V in 60 hours when it has a load of only 10mA.
A Cmos 555 has an average supply current of 0.12mA (almost nothing) so a 9V alkaline battery will last about 7 months.

The 3V battery is doing hard work so it won't last long unless it is pretty big.

alright, so if i use a normal 555 timer, the whole thing will last about 2 days, right? thats what my calculator says anyways...

how long, exactly, will the 3V battery last if its two energizer AA's?
 
alright, so if i use a normal 555 timer, the whole thing will last about 2 days, right? thats what my calculator says anyways...

how long, exactly, will the 3V battery last if its two energizer AA's?

The only effect that the battery(ies) on the 555 side will have on the life of the battery on the singing card side is that the longer the 555 side lasts, the more times the card will have to sing. We don't know what the 3V battery is though and we don't know what the current draw of the singing card is, so it's a little hard to guess how long the card itself will last. And any calculations would probably assume a fresh 3V battery in the card itself, which probably isn't the case by this point.


Regards,

Torben
 
The last sketch has a green LED that will probably instantly burn out since it doesn't have a current-limiting resistor.
I don't know why there are diodes all over the place that have no function.

We don't know how much current the greeting card uses so a calculation of how long two AA alkaline cells will last is impossible.
 
The last sketch has a green LED that will probably instantly burn out since it doesn't have a current-limiting resistor.
I don't know why there are diodes all over the place that have no function.

We don't know how much current the greeting card uses so a calculation of how long two AA alkaline cells will last is impossible.

...uh, there arent any LEDs in this circuit at all...
there are some poorly drawn caps though (the way to tell is that they have capacitance ratings near them, except for one on the card circuit.)

but, for the other part of your post, what exactly is it that determines how much juice the card will use up?
 
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The last sketch has a green LED that will probably instantly burn out since it doesn't have a current-limiting resistor.
I don't know why there are diodes all over the place that have no function.

We don't know how much current the greeting card uses so a calculation of how long two AA alkaline cells will last is impossible.

I think we're looking at different sketches. The only one I see on this thread has no discrete diodes at all, light-emitting or otherwise.


Torben
 
but, for the other part of your post, what exactly is it that determines how much juice the card will use up?

The card's current draw will depend on how it's designed and built. If you have a multimeter which can read current then you could put the meter in current mode, insert it in series between the singing card circuit and the 3V battery, and trigger the card to sing. This will tell you what kind of current it's drawing while it sings. In other words, remove one of the leads from the battery and attach the lead to one of the meter probes. Then touch the other meter probe to the battery terminal the lead was attached to, and trigger the card. The battery current will then flow through the meter and can be measured.

Unless it's a stunningly bad design it will draw more current while singing than it does while quiet. :)


Torben
 
Instead of attaching his schematic to his reply here, he linked to his 4 projects over at Photobucket. One project has a green LED and some useless diodes.

The loudness of the speaker on the card determines how much current it uses from the 3V battery.
But greeting cards that I have heard have a tiny squeaking piezo speaker that has very low loudness and uses a very small battery.
 
All Hallmark singing cards turn off at the end of the tune and take less than 1 mircoamp. You do not need a timer.
You have to explain what you really want to do.
 
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Lol, I helped him with the schematic by I didn't think of that, even though I knew it. :D
 
what if i put a 100uF capacitor in the place of the 1000uF cap., and set up a decade counter so that the output after it counts to 10 goes through the relay and then goes to reset?

in summary, make the output of the 555 timer 10x shorter of a wave and make a decade counter count ten waves, then trigger the card.
 
Instead of attaching his schematic to his reply here, he linked to his 4 projects over at Photobucket. One project has a green LED and some useless diodes.

The loudness of the speaker on the card determines how much current it uses from the 3V battery.
But greeting cards that I have heard have a tiny squeaking piezo speaker that has very low loudness and uses a very small battery.

ya... im still a rookie and i had some ideas.
 
what if i put a 100uF capacitor in the place of the 1000uF cap., and set up a decade counter so that the output after it counts to 10 goes through the relay and then goes to reset?

in summary, make the output of the 555 timer 10x shorter of a wave and make a decade counter count ten waves, then trigger the card.
Make a CD4060 oscillator/counter instead of a 555 and a separate counter. The CD4060's counter can divide by up to 16,384 so the oscillator capacitor can be tiny and it uses a very low current and low supply voltage so its battery can also be tiny.

The "relay" is a low current tiny transistor or two.
 
Make a CD4060 oscillator/counter instead of a 555 and a separate counter. The CD4060's counter can divide by up to 16,384 so the oscillator capacitor can be tiny and it uses a very low current and low supply voltage so its battery can also be tiny.

The "relay" is a low current tiny transistor or two.

again, I am just a rookie. I would rather stick to using the 555 for now, as I already know how it works. thanks for the suggestion though.
 
Let's turn it around: how long would you *like* this thing to keep working? Do you have a purpose in mind, or is it just a straight-up "as long as it can go" thing?


Torben
 
id like it to last as long as it will go. id like it to last at least a week though.

also, i was considering using the CMOS555 as suggested earlier, as it uses up alot less of the battery, and it will work on 3V instead of 9.
 
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id like it to last as long as it will go. id like it to last at least a week though.

also, i was considering using the CMOS555 as suggested earlier, as it uses up alot less of the battery, and it will work on 3V instead of 9.

when i said a week, i was talkling about the battery powering the 555 timer. i would also like the battery powering the card to last the same time too, if not longer.
 
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