JRC GED

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Duty cycle. Duty cycle is the percentage of time that a pulse is on during a single on-off cycle. For example, as shown in Figure 2, Panel A, the GED pulse is on for 25% of each cycle. Current is on for 3.125 ms, and off for 9.375 ms. The total time for one cycle is 12.5 ms.

During the design of GED, eight volunteers tested the perceived aversiveness of the stimulation at 10%, 25%, and 50% duty cycles. They reported little perception of aversiveness at a 10% duty cycle, and definite aversiveness at 25%. They found the 50% duty cycle only slightly more aversive than the 25% duty cycle. Because the 50% duty cycle was thought more likely to cause skin irritation and was judged to be only slightly more aversive than the 25% duty cycle, we decided upon a 25% duty cycle for the GED. The duty cycle may be adjusted from 1% to 90%.

Current. When operated across a 24 kΩ resistor, the GED produces a voltage of 106.3 V (rms), and a current of 4.42 mA (rms). The corresponding peak values are 272 V and 11.33 mA.

In order to find out the level of current during actual stimulations, tests were conducted on 10 BRI staff members, who volunteered to participate. Each volunteer received one 200 ms application of GED to the forearm. Previous testing at BRI had shown that peak current was reached within the first 200 ms of a stimulation to the skin. The same measurements were taken as described earlier for actual SIBIS stimulations. Table 2 shows the results under the columns headed "G.". The median peak current for the volunteers was 29.2 mA (range 12.8 mA to 39.6 mA), and the mean was 29.6 mA. Median and mean rms currents were 14.6 mA and 14.8 mA, respectively. The median impedance for the 10 volunteers was 4.0 kΩ (range 3.1 kΩ to 13.4 kΩ); the mean was 5.0 kΩ.

The maximum peak current possible from GED, measured by applying GED to a 100 Ω resistor, was 56 mA. This level of current would not be generated when the device is applied to the skin, however, because skin has a typical impedance of two to five kΩ.

Pulse repetition frequency. Pulse repetition frequency refers to the rate, in pulses per second (pps), at which pulses occur within a pulse train. Informal tests on a few volunteers during GED’s design phase suggested that perceived aversiveness decreases rapidly when the pulse repetition frequency is below 40 pps or above 120 pps. GED was given a pulse repetition frequency of 80 pps. (80 Hz) This setting may be adjusted by a technician to any value between 40 and 120 pps.

Duration. The duration of a single GED stimulation is completely adjustable. We have selected a duration of 2.0 seconds for the typical application.

For our test purposes, we use a 5 k Ω. load (5000 ohms), which most closely simulates average skin resistance. This produces 65 vrms output with a median current of 13 mA for the GED and a 130 vrms output with a median current of 26 mA for the GED-4.

Be careful with that. Electricity isn't just a toy. If you want a publicity stunt, your best bet might be to buy one of those devices so that you can't be accused of making it look worse than it is, and there will also be less risk of you screwing something up and getting seriously injured.

It would be the best way, but I don't think they're commercially available - unless you know somewhere I could get my hands on one...

You could look for the WhistleStop or SIBIS (the two shock devices listed in your link as being commercially available) or look for similar ones. True, it won't be the same effect, but if you used SIBIS and then said "The GED used at JRC was designed because this one's shock was thought to be too weak" people might start to pay attention.

Out of curiosity, I assume this demo involves you being electrocuted, and not those you are demonstrating to?

Yes, JRC will issue such a statement, and it will be harder to contest such claims if you are using a home-made device, even if it is technically identical to theirs. A real, commercially available device can at least be referred to as "similar to those used at JRC" since the technical specs of each should be publicly available for comparison.

EDIT: Never mind, these are only commercially available to doctors and psychologists anyways. Good luck if you decide to build your own, and above all, BE CAREFUL!! !

Thanks, will do! Before I actually attempt to use the thing, I'm going to try to get a licenced electrician to give it a once over - which isn't exactly a foolproof method, but it at least gives me a small safety net...

If you decide to go through with this, there would preferably be a medic of some sort nearby. Also, check with a licensed physician beforehand to ensure you don't have any heart problems, etc.

Anyways, does anyone have any advice on the technical side of this project?

For some people, even the slightest electric shock is a health risk.

Again. Don't do it.