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simple ac dc field detector circuit


steven

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:) well here it is , i spent time every  day working on this  and it works great, now, all i have to do is switch it on and  piont the ereal towards any ac or even dc voltage source, even high voltage ,  and the leds will respond. first of all if i aproach the wall switch the red and green leds start blinking at a certain speed ,  but the range of the response of this circuit is less than that of a tv set as it has high voltage in it to so a few feet away it will blink the leds , now when i aproach my high voltage circuits the leds reaction changes and they both come on and  alternate as you move the ereal near the high voltage circuit, in this mode the leds dont blink  like it dose near ac but will alternate slowly depending on where you move the ereal near,  or they come on and stay on and slowly flicker ,when near the high voltage circuit. so this would be like a moveing charge detector or better, i used tinned coper wire  from the printed circuit board that goes to the short ereal, and , the printed circuit board i made with the help of the alliuminium coke can ic printed circuit assistant tool i designed , thie circuit seems to give a great indication to the distance the electric feild of my pc so, as i aproach it with thew ereal the leds react a few feet away. and i bet this handy circuit will pick up a tesla coil feild from even further away or even maybe a ufo with a strong em feild to or underground ac dc power source

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:)heres the latest  pictures , one is the bread board design  for this and the final decal work  on the circuit box  which was an ac power transformer box of some kind, another test i allso done was to have it near the pc dureing its shutdown stage and the  leds respond by flashing and as the pc powers down , one led will be left on

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Hi Steven,
The IC is Cmos with inputs that can be destroyed by static electricity when they aren't terminated. Therefore I have added a 1M resistor in series with the antenna to reduce damage from static.

Your circuit had outputs pin 7 (output pin 6 on your breadboard) and pin 10 connected together which would only cause heating in the IC and quickly drain the battery. Therefore I have removed their connecton together.

Your circuit had two diodes that didn't do anything. I have removed them.

The CD4017 is a 10-step sequential counter that would step forward one step with each positive-going signal picked up by the antenna of mains hum or other AC. LED1 indicates on the 1st step and LED2 indicates on the 10th step. A strong DC field would stop the counter, randomly, so usually neither LED would be lighted.

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audio guru and ante thankyou for the input, the decade counter is made by texas instramnts and the diode is being used by the circuit, i just pulled it out and the circuit went dead, and allso theres been no heat whats so ever in this circuit , and what you see in my circuit, i dont think ive included any changes or modifications or did i  i biult this circuit and everyday been trying to improve it and ive had no troubles what so ever  anyhow  one of my wires link may not be nessisary but for some funny reason  i think its helping  the circuit.



















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:)i did have the details of that ic written down but cant find it but static sesitive ics normally have cmos written on them , i remember this one dident have it  anyhow when i mopve close to my high voltage circuits in action the leds flicker like it dose near ac but as you get closer they stop and stay on  and at times they just come on both and flicker slightly as if they are responding to the frenquency of the voltage .  have more test to do yet, but i even bring it near the static screen on the tv and pc and with the charge left on the screen it hasent blown this circuit yet  so how it holds out ok is a mystery to me

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:)thankyou for your input audio guru  the details on the ic are so hard to see that i have to use a magnifying lense in light to see it so how do you see it on the actual ic  some 4017 ics are made by other companies to like moterola as the letter m on  it others i can see but this kind of ic the details are so faint and hard to see it has ti on it

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:)ill remove the shorted wire then that goes to pin 6

Good, but it connects to pin 7 on your schematic. Your battery will last longer without having those shorted-together outputs fighting with each other.

All companies make the 4017. Motorola's has their part number of MC14017.
I think they mark their numbers with a laser beam, so I hold it on an angle and see the reflection from a light.

Did you try replacing the diodes that do nothing with a piece of wire?.
Doesn't it stop counting without an LED lighted?
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  • 3 weeks later...

:)i had a look inside this electronic stud finder and found only an ic and a few transisters and resisters and  no coil just the circuit board plate so this is like i emagine some kind of proximity detecter as the led allso reacts to my hand thats why the unit has 2 arows on it telling you where to hold it , the circuits led reacts really fast when i turn on my high voltage photo flash capacitor from many feet away, the led comes on instantly

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