Static Field Detector for Sale

You can own a highly sensitive static field detector for paranormal activity.
After 6 months of continuous use of 3 prototypes I am highly confident in the design.
It was great fun laying out the PCBs and building these units (now dubbed SFD1): they are ready to ship.

User Manual [Link]

Updated Parts List [Link]

If you just want to get the PCB [Link]

The PICAXE Code [Link]

My other interests [Link]

Static field Detector gets a Professional PCB

I have been building a lot of microprocessor-based projects lately, and the most tedious part is all of the point-to-point wiring required. Cutting, stripping, tinning and soldering consumes hours. I have used on-line PCB fabricators before, but the cost has been high (like $250 for a few boards), so I was looking for another solution. The SparkFun Web site (from which I buy a lot of my parts) posted a service for permitting hobbyist to submit their designs in the un-used margins of commercial panels of production runs for a greatly reduced cost. They even provided a link to Eagle, a free (for personal/no commercial use) schematic capture and PCB layout software. The SparkFun site also has tutorials on using this SW to make your own Gerber files (the essential files to get your boards produced). You must follow their tutorials religiously, and download their SparkFun library, as I found numerous ways to screw up my design and have it rejected by the batch processor. 2 Days of effort finally yielded a design that did not violate CAD rules, and was accepted. The boards came to only $9.19 each.

 

http://batchpcb.com/index.php/Faq#what_are_the_pcb_rules	Will make your boards cheap!
http://www.sparkfun.com/tutorials/108	Must follow religiously!
http://www.cadsoftusa.com/downloads/	Download Eagle Schematic Capture/Layout
http://www.viewplot.com/info_files/vpl_download.html	Used to check your Gerbers
http://www.batchpcb.com/product_info.php?products_id=81452&check=fbee6c6fe66f57e15f9f3a0b5c50adb6	static field detector PCB for sale

My other interests [Link]

Static Field Detector Early Warning System

I had built a simple static field detector before, that would turn on an LED when a comb or a piece of cellophane was brought near its antenna; but I was able to enhance the sensitivity of the circuit using a PICAXE microprocessor. The basic circuit centers around a FET (field-effect transistor) with a long wire on the gate as the static electrical probe. The FET's drain to source current changes in response to minute changes in the gate voltage, and since it is high impedance, it won't drain away static fields. The FET's drain is connected to the ADC (analog to digital converter) of the microprocessor where it is represented by a number between 0 and 255 (8-bits). Through observation in debug mode I set a high sensitivity threshold at 60 and a low sensitivity level at 100. When the static energy exceeds these levels, a brief chirp sounds from the piezo speaker (not loud enough to disturb my wife) and the LED turns on. This little system can detect a charged comb (just run it through you hair) from a meter away. I tried it last night, and it only went off once; at 3:04AM! I am quite pleased with this result. Whatever is bugging me in the 300AM hour is detectable and generates a static field. For a few dollars in parts I might build a bunch of them and distribute them around the house.

The circuit diagram [Link]

The BASIC code [Link]

The parts list [Link]

My other interests [Link]