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Garden lights circuit will this work

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I would like to light 6 leds at the most 8.
hi Jake,

Have you had the time to measure the voltage across each LED.?
If you connect a 3.2V and a 3.8V LED in parallel, there is a good chance the 3.2V LED will quickly die.!
 
If I use the 250 ohm resister to test I do connect that to the battery on the postive side and check each one of the leds seperate. I only have a 220 ohm resister will that work?
 
If I use the 250 ohm resister to test I do connect that to the battery on the postive side and check each one of the leds seperate. I only have a 220 ohm resister will that work?

hi,
From a 6Vbty minus the 3V of the LED will give 3V across the 220R.

Which is 3V/220R = about 13mA , so thats OK.

I'm signing off for today.:)
 
Thanks for your replies I will look for your post later on I to need to go someone where and will be back later this evening.
 
A photocell is an LDR. In bright light it is from 100 ohms to 1k ohms and in the dark it is megohms.
 
A photocell is an LDR. In bright light it is from 100 ohms to 1k ohms and in the dark it is megohms.

But is it a Cds photo-resistor.?

I suspect as we are of a like vintage, the term photo-cell used to refer to glass vacuum tube photo-cell .?
 
But is it a Cds photo-resistor.?

I suspect as we are of a like vintage, the term photo-cell used to refer to glass vacuum tube photo-cell .?

Glass tube. lol, now that is vintage :) :D
 
Thanks for your replies I will look for your post later on I to need to go someone where and will be back later this evening.

hi jake,

Look at this circuit.

As the LM393 and the MOSFET are both dual devices, you could make two LED lights.

Let me know the results ofthe LED voltage tests.:)
 

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Sorry I did not get on the computer last night, but this morning I checked the led with the 220 ohm resistor and the voltage was 2.4 volts just enough to light the led but not bright at all.
 
Sorry I did not get on the computer last night, but this morning I checked the led with the 220 ohm resistor and the voltage was 2.4 volts just enough to light the led but not bright at all.

hi jake,
If that is an LED from that pack marked 3.2V to 3.8V thats not a good sign.
Were all the LED's 2.4Vdp.?

If the Vbty was 6V the LED has 16mA with a 220R, usually standard LED's are fairly bright with 20mA.

Did you see the circuit I posted, with those dual IC's and the dual MOSFET you could have two garden lights,
master and slave.

Do you follow the circuit OK.?:)
 
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Ok on the photo cell I used another one out of the package and here are the results I got in the light measures 4k with my finger over the cell it measures 36k I am guessing that are better results.

I've used the cd cells in that Radio Shack package for dozens of circuits and experiments. There are three sizes represented in the package. Only the middle sized works with any dependability. However, I have used it with any number of different circuits, including exactly the one you posted. Use an NPN transistor, (2N2222 is ideal) with at least a 1K ohm resistor paired with the CD cell in the voltage divider.

I do not think you will have much success, however, trying to drive as many as eight LEDs off just one circuit. With five volts Vcc, as an example, I can only get two red or green LEDs to work as designed in series with a suitable current-limiting resistor.
 
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I have been looking at your diagram and I think I understand it, I am going to check out RadioShack web site and see if they have all the part, that is the only place around here that has any electronic parts.
 
I have been looking at your diagram and I think I understand it, I am going to check out RadioShack web site and see if they have all the part, that is the only place around here that has any electronic parts.


hi,
The LM393 is a very common device.
That FET is less than £0.5GBP in the UK.

If you have trouble with the MOSFET, any type will do that has the following.

At least 0.4A current, operating voltage at least 12V, Gate turn ON voltage of 1V+

Whats the size of the 6V battery.?

EDIT: just rechecked the UK prices, for 1 off's
FET is £0.14
LM393 is £0.36

I think you are located in the States.?
 
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Maybe your 220 ohms resistor is actually 2.2k ohms or 22k ohms.
Maybe your 6V battery is dead.
 
Battery size 4.5 AH, 6 volt. I think RadioShack will have everything, I am going to print the diagram out before I go, and take it with me. Going to try to get there this afternoon.

Just wanted to thank you for your help, I bet I will be asking more question as I build the circuit.

I am in the states, and I love the UK, one of my favorite performers is Gary Numan love his music. Have you heard of Him?
 
Battery size 4.5 AH, 6 volt. I think RadioShack will have everything, I am going to print the diagram out before I go, and take it with me. Going to try to get there this afternoon.

Just wanted to thank you for your help, I bet I will be asking more question as I build the circuit.

I am in the states, and I love the UK, one of my favorite performers is Gary Numan love his music. Have you heard of Him?

Yes I have heard of Gary.:)

BTW just to double check, that circuit is working on my project board.

I still need to know, have you checked ALL those pack of LED's.

Take note of what 'agu' said about the resistor value used when testing.
 
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I did not make it to RadioShack today, but what I thought was a 220 ohm resistor really was a 220k so the reading I got was incorrect, I will get the correct resistor also when I get to RadioShack.
 
There are plenty of cheaper places than RadioShack but you need to order over the Internet.
 
I am on the way to get the correct size of resistor to check the LED's I thought I better do this first before purchasing all the other parts. I will check the led's tonight and post the results.
 
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