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This development actually was a spin-off from an experiment with light coming from the sky that can be found here.

In this experiment I observed that daylight shining on a phototransistor with a substantial light intensity causes noise that shows pk modulation. During my experiment I tested light sources different from daylight and found out that ultraviolet and yellow LED light are causing more or less the same effect. That opened the path to a device I called LINGER (Light Induced Noise Gated EVP Receiver)

Schematic of electronic circuit

As you can see the electronic is rather simple.


The first stage is made of the transistor K2 that drives the LED to excite the phototransistor K3. The LED light can also be modulated by an external audio source through the connector X1. Transistor K4 is a tricky feature that is boosting the output of the noise from K3. The transistor K5 is levelling the amplitude up so that the final stage made from  the SSM 2167 can work with it properly. This circuit is a microphone signal conditioner. It amplifies and compresses the signal and routes it through a noise gate. The noise gate works as a very effective amplifier for pk modulation.

What makes working with this device so appealing is the fact that you only need one knob to adjust the pk modulation for maximum and a second knob to adjust the external modulation. However you also can run the LINGER without modulation.

The device is powered by 8 NiMH batteries.

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Sound examples without external modulation

Here some sound examples gained from the LINGER without external modulation. They were processed by reverb, voice pitch and 15% denoising.

"Der Herr dort segne unseren Test" -> "The Lord there bless our test"

"Du hast den Test bestanden" -> "You have passed the test"

"Es ist ein Fenster auf" -> "A window has opened"

"Heut mit Grenzen" -> "Today with limits"

"Die schmecken sie selbst" -> "They taste them themselves" This sample was processed with Michael Lee's itc-translator.


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Sound samples gained with external modulation

For this test I used the song "Stranger in Nevada" from the band "Matchbox". It's an old song back from the early 80's. Because it is instrumental there are no voices that could be misinterpreted as spirit signals. Some of these samples again were processed with Micheal Lee's itc-translator. The rest was processed by reverb, voice pitch and 15% denoising.

"Da kommt er vor dem Leid" -> "He arrives before the suffering"


"Dann wird Mörder" -> "Then turns into murderer"


"Deinen Freund kannst nicht beigehen" -> "You cannot attend your friend"


"Dem sprach der Elch net" -> "The moose did not talk to it"


"Die leichte Spannung wählt" -> "Choose the low voltage"


"Landwehr Krieg meine Armee" -> "Defensive dyke, war, my army"



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