NE555 VLF transmitter

[WM6]

Simple VLF transmitter with aerial coil wire antenna and changeable frequency can be build using wide available NE555. Not with ideal sine wave but usable.

Potentiometer should be, for more precise frequency selection, multi-turn one (if possible), but not required.

Antenna coil data: outer coil diameter >22cm, wire diameter 0.25mm, coil resistance >33 Ohm, number of turns approx 111, inductance about 5mH, wire length needed about 80meters.

PCB dimension 2.1" x 1.6".

[WM6]

Proposed circuit generate bursts of selected frequency.
This can be usable if we select frequency out of human audible range (say > 22kHz) which can be then on RX side demodulated to make bursts audible. We can lower C2 to 10uF.

[Fred]

Hi WM6,
May i ask what is the purpose of the circuit, (except scaring mosquitoes) ?

[WM6]

Hi WM6,
May i ask what is the purpose of the circuit, (except scaring mosquitoes) ?

Hi Fred,

purpose of this circuit is, as previous stated, VLF transmitter (very important thing in some sort of electronic dowsing).

DO not be fooled by a weak signal, it is even too strong and need to be limited (limiter not included in circuit yet, but is very simple to apply one) for best sensing results.

You are free to use this circuit for scaring mosquitoes, if your mosquitoes warriors believe in electronic dowsing.

[J_Player]

Hi WM6,
May i ask what is the purpose of the circuit, (except scaring mosquitoes) ?

Hi Fred,
Mosquitoes are not scared from VLF transmissions.
But if you want to use this circuit for mosquito scaring, you can make a modification to the output at the antenna coil.
By adding a single transistor and resistor plus a piezoelectric transducer, you can make audible sounds which follow the bursts that are being sent at the coil.
Of course, you want to choose sound frequencies that mosquitoes hate, so they will stay away.
This can be good for a dowser when he is treasure hunting, or for a non-dowser for when he is at a picnic lunch during mosquito season.
But be careful... do not adjust to frequencies that attract mosquitoes.

Of course, do not publish what kind of transistor or buzzer ... (spies are watching).


Best wishes,
J_P

[morsuvari]

tHi Fred,

purpose of this circuit is, as previous stated, VLF transmitter (very important thing in some sort of electronic dowsing).

DO not be fooled by a weak signal, it is even too strong and need to be limited (limiter not included in circuit yet, but is very simple to apply one) for best sensing results.

You are free to use this circuit for scaring mosquitoes, if your mosquitoes warriors believe in electronic dowsing.

Thanks WM6,it is very nice.
-morsuvari-

[Metaldude]

What is the VLF transmitter used for? (Forgive my primitive knowledge), that is, how is it used to find minerals?

[Dave J.]

What is the VLF transmitter used for? (Forgive my primitive knowledge), that is, how is it used to find minerals?

Finds minerals through the use of lots of imagination.

Like a 5 year old kid fending off space invaders with a ray gun comprising his mother's keychain flashlight.

No matter where you go, there are no space invaders, and there are minerals. So it appears that both methods are effective.

--Dave J.

[mustefa ubram]

VERY NICE WM6
What do you use software to simulate the circuitS?

[Dedevil]

Heart beat duty cycle

Nice circuit and diagrams, reminds me of the thread Geo started a while ago but he didnt have a transmission on the end.

While using my spring divining rod i noticed that the movement towards the target ( a creek) was at a rate of around 1 per second.

So thought what would be changing the electrification amplitude of my body at that rate?

The conclusion i made was that it is simply the heart beating. So i think as we are trying to reproduce divining then why not use the same duty cycle as a human heart beat? Can anyone with a scope look into it? Is it a 50/50 cycle?

Also i think the power of the diviners transmission does make a difference to the distance being divined. I have heard of American indians meditating before releasing a divining signal to get greater distance and accuracy. They used it as a type of communications system with others in the tribe who were away hunting. The meditation must help store the charges inside the body. The charge is releaed in a flash and leaves that feeling of shivers up your spine.

I tried this meditating type of divining once, and funny enough a mosquito came along. Without moving a muscle I put all my thoughts and energy into the shoulder it was about to bite me on. I could hear it getting closer and closer then ZAP! I had charged up so much that i discharged onto the mosquito! The discharge didnt kill the mosquito like a bug zapper would but it flew off making a strange sound.

rgds

[WM6]

What do you use software to simulate the circuitS?

CW from New Wave Concepts.

[Metaldude]

I have no idea what you are talking about.

[Dave J.]

Neither do they, Metaldude. They're all BS'ing you. The circuit doesn't have anything to do with locating metals or minerals-- unless you want to pretend that it does.

--Dave J.

[Metaldude]

Thanks for that.

[Metaldude]

There's lots of them on Google, use: Images, also people who listen to VLF atmospherics have a substantial experience in VLF receivers. What is your application?