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Can anyone help me with this.
I need programmable frequency generator which will work like described below.
Something I can setup like this
program 1) 20Khz sinus, 20 minutes -ON
program 2) 460Khz sinus, 25 minutes - ON
program 3) 20Hz sinus, 40 minutes - ON
program 4) 201Hz sinus, 20 minutes -...
I will, thanks.
For now I solve this by putting transistor in pcb wrong way, I changed E and C and put in larger resistor on base like 68Kohm
Red still lit when green is on but verry little.
Thank you, a third circuit is what i had before but now I have 2 color 3 pin common cathode led.
Problem is I already have PCB board with my circuit above, how to solve that?
Both LEDs are on the same source but one goes ON when output of NE555 is high and other when it is low over PNP...
I have this circuit and when I start NE555 led goes RED and that it doesn't change to GREEN, relay turns on and off but LED doesn't change, I think it is problem because difference on transistor B/E is about 0.84V.
Any Idea how to solve this problem??
I have this small LED and PIR light now when sensor detect motion it turns ON and after 2 minutes it turns OFF.
Now I like to change circuit to Light turn of slowly, like dimm to zero, so it takes about 20 seconds to light turn of by dimming.
But don't know how.
here is circuit
**broken link...
I have this modul for ardurino and I like to use it to protect my power supply against short circuit.
Problem is because difference is only 185mV on 1 A.
So how to turn rele on with this module with that low voltage difference?
If someone have better idea how to turn off power supply when short...
Yes this is idea now how to do it.
I have also found another chip which is not expencive and I think may work and it works to 40V.
It is cmos DG408.
The best will be if I could to that with some microcontroller.
Yes I know that AVR micro controllers can do that but I have no knovledge of AVR and programming it that's why I look at 4097.
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I will use voltmeter to check voltage of 8 cells in battery. Chip will go from one cell to another every fev seconds and at output of chip like...
It can be setup how low you will discharge I just put value of 3.8 it can also be 3.7.
Problem is how to switch woltmeter input from one to another cell to measure it??
I have lipo battery with 8 cells so total voltate is 33.6V
Now I need to measure each cell and when first one drops to 3.8V when discharge relay will turn off.
Problem is now how to measeure each cell because they are serial connected.
I thought to use Cmos 4097 which has 2 x 8 channels to...
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