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The circuit I found online was 9v but it runs good on 3v.Then with the 3V supply, the base current is only 2.3V/100k= 23uA and it saturates well only when its collector current (LED current) is only 0.23mA.
That is why I said the original 47k resistor (used with a 9V supply) has its value too high.
Then with only 3V the base current with the 47k resistor is only (3V - 0.7V)/47k= 48.9uA but the transistors saturate well when their collector currents are 489uA which results in a very dim LED especially if the hFE of the transistors are a little low and the 3V battery voltage has dropped a little to 2.7V.The circuit I found online was 9v.
All the parts are rarely all the same. The transistors have a wide range of hFE, the resistors and capacitors have plus and minus tolerances that are never the same.Could it be that your simulated transistors are exactly alike? How could the circuit be astable if all the components are the same?
No. The datasheet for the LM3909 shows a duration of only 6 months for a much larger AA alkaline cell. My LM3909 had a duration of one year using a huge D size alkaline cell.There seems to be an old chip that could do this for 2 years on a coin cell, the LM3909.
I posted about the LM3909 and included the schematic in your link way back on the first page of this nine page thread. I don't know how you could have missed itThere seems to be an old chip that could do this for 2 years on a coin cell, the LM3909. Here is a circuit that could be used instead of the IC - http://pigeonsnest.co.uk/stuff/picprog/single-cell-led-flasher-two-year-battery-life.html
I saw the info about LM3909 but information said it has been discontinued several year ago. Anyone that has them for sale cheapest price is $8 each some people want $50 each.I posted about the LM3909 and included the schematic in your link way back on the first page of this nine page thread. I don't know how you could have missed it
Today I see several LED flashers are not flashing, LED is ON all the time but no flashing. Tomorrow before the tornado I need to check the batteries 1 month much be the limit for AA batteries.