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Hello, Im trying to make spirit box for EVP but i dont have enough knowledge for that. As further I came I need a mic, some type of frequency raiser and an amplifier for speaker and output - speaker.

I dont know how to make frequency raiser and is it even possible with out digital electronic?

So can someone make this circuit?

And i also have arduino so if it can help...

UPDATE: Is i possible to make it with "mixing console" curcuit?

Do you want to make a proper 'ghost box' receiving random snippets of radio transmissions or are you looking for an audio frequency pitch shifter for use at seances?

For anyone puzzled about this here are a couple of links: http://www.skepticblog.org/2012/05/14/ghost-box/ and http://huffparanormal.com/2014/06/spirit-talk-the-difference-between-e-v-p-and-ghost-box-replies/

An example of EVP: https://www.youtube.com/watch?v=pYufeRxaMtg

Im looking for acctual Ghost Box/ Spirit Box

As further i came is set low pass filter under 20Hz and everything under 20 Hz to charge capacitor and to speed up to discharge that capacitor to 100Hz per second

anyone got any idea for circuit?

Most folk seem to use mobile phones or transistor radios as a starting point because to buy one costs much less than buying the components separately. Here are three examples: https://www.youtube.com/watch?v=1PqjzWcb8UY or: https://www.youtube.com/watch?v=sQnm-N05mvk or: https://www.youtube.com/watch?v=TZHPUnocZFk

ps - if you look down the third link, there are further links to constructional data. And if you read through the comments you will see reference to radios with the squelch turned right down. I think this is the strongest method provided you live in a very active area. No need to build anything, you can get going with a relatively low cost scanning radio receiver provided it has squelch. Don't worry about the microphone side of things, just speak normally and I'm sure your chosen entities will hear and respond.

i clearly doubt that ghosts uses FM frequency to talk. My idea was to use sound modulation to raise frequency of infra sound so it would be hearible.

I tried to design a frequency shifter based on a heterodyne bat detector but ran into two problems: first the local oscillator frequency is in-band, and second the signal after conversion is very narrow band (10 Hz each side of fosc). Not a goer, I'm afraid.

Another method is to use a multi-speed tape deck. Run the tape very slowly when recording and very fast to replay. This will get infrasound up into the audio band. Not instantaneous to us, but not much of a delay at ghost speeds.

Well I dont have multi-speed tape deck; but ill try to use EVP maker. This program can speed up track.

Thanks anyway Mike.

Glad to help, and glad to hear you have a way of processing the data. Spirit messages with their limited bandwidth must take all day to transmit, but I guess they have plenty of time available.