View single post by EVPDave
 Posted: Oct 7th, 2007 07:19 AM
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EVPDave

 

Joined: Mar 7th, 2007
Location: USA
Posts: 206
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 Hi Laura, I don't think many people work with EVP maker. If they do I don't see many examples posted here.  Most sites seem to discourage it's use although I don't know why, other then the fear of false positives. The resultant sessions are very tedious to listen to as 99.9% of the output is not EVP. This could be another reason it is not widely used, it requires great patience and listening skills.

I didn't dwell on this system/method too long and moved on to other projects. Looks like I spent two or three days working with it and I have posted the best examples from those sessions. If I can find the software on my other computer I could draw up a crude diagram, a picture would not show much other then a VCR and a vacuum tube.. I remember the tube is a 931 photomultiplier, I had to build the voltage divider for the tube socket although I think pre-wired sockets for these tubes are available if you search for them. The transformer to build the optical transmitter was from Radio Shack with a 1:1 ratio, 600 ohm. The LED was nothing special, any color will work with the tube as well as a UV LED. I may have used a pre-amp into the line-in of the VCR as they typically require a higher level audio input. The VCR is old and has developed a problem and I need to repair or replace it before I could use it again. These VHS VCR's with analog audio make excellent recorders for EVP work. Very pleasing to listen to compared to digital recording, your ears will feel the difference. Oh, and the photomultiplier must be used in the dark, no monitor light or outside light, it's very sensitive.

Hope this helps a little, thanks,

Dave

Last edited on Oct 7th, 2007 07:25 AM by EVPDave