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A project log for EMF Pickup Device

An enclosure for a hacked cassette player pickup and processor so you can listen to EMF waves

David TroetschelDavid Troetschel 01/07/2019 at 19:570 Comments

Okay; I'm doing it.

I still plan on fixing design files for previous designs but I'm going to try and make a new PCB for this thing. I keep finding contradictory information though, based off of the square reader it would seem that a tape head transducer could just be hooked up to an audio processor circuit and played, but its difficult (for me) to find decent plans for such a standalone contraption.

I started reverse engineering the MS 01-118S-01 board but almost immediately ran into a roadblock trying to find the read head.

And..... NO.

Fortunately I seem to have found plenty of alternatives to what they used:

http://www.durascanheads.com/standard/index.html

https://www.brushindustries.com/product-lines/low-cost-standard-heads/low-cost-standard-heads/page.aspx?id=1139

http://www.apolloelectronics.com/en/products_show_3_16_178553607.html

Again though, I don't really know which would be ideal other than that it should probably be single track... Although if it was two track it could potentially be used for stereo?

I know that I need to amplify this circuit and that the SCR uses the https://www.electroschematics.com/4375/tda-2822-stereo-amplifier/

Others have used the http://www.ti.com/product/lm833-n which is about $1 each.

On the processing end.... https://www.electroschematics.com/12327/simple-sound-processor-circuit/

Ultimately I'm not looking for any noise cancelling features, a delay might be useful but isn't really required.

The smaller this can be the better for obvious reasons, the current models are a little too wide in my opinion due to batteries and stuff..

Cool, so what does all of this mean?

This project is taking a step in a slightly different direction:

1) A new project page will be started soon detailing a preliminary design of a new circuit board and subsequent designs. This will likely take on the form of a kind of watch like processor and finger tip sensor section. This is a fairly ambitious undertaking as far as I'm concerned since I'm basically winging this.

2) This page will get updated with updated designs, but only for one board probably. I just don't see the point in working around the existing MS board, its too sloppy in its construction (sorry, but not sorry.)

3) A third project will likely spawn from the new board, assuming I can get it to work. This will be more oriented towards actual data acquisition and sampling rather than sensory augmentation.

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