Inside an "electrotherapy" device
🕑 Added 2024-12-28 00:20:59 +0000 UTCI can't even imagine how many of these things are in use. They're sold for pain relief, muscle building and pleasure. Their history goes back to the Victorian era when battery operated electric shock machines were used to "treat" various medical ailments.
Comments
Mike Page
A bit like a Proving Unit. But I wouldn't recommend trying one! It'll source >= 20mA.
Big Clive
In one of the first electrician's guides they actually suggested touching the bare wires to feel if they were live. Then they removed that bit.
Robin Cooper
So true, the understanding of and safely dealing with electricity has come on a long way since that book was written in 1926.
Big Clive
I think resistors would be much safer. Human current is best kept to a few tens of milliamps max and a variac does not provide proper separation from the mains supply.
Robin Cooper
An old book has been mentioned on the Vintage Radio forum that has further information on this subject even to the point of wiring a patient up to the mains with a few bulbs for protection and a variac. The book is called "Medical Electricity for Students" by Browne
Big Clive
The capacitor is charged to over 100V and then that is pulsed to the body. I'm not sure what the output stage's impedance is.
Big Clive
Much cheaper though and somewhat safer.
adrian
Not as pretty as a violet ray
Simon Allen
I have wondered about the output voltage. I know the amps are low, but can the output voltage be measured?
Loscha
I thought that was going to end with "and we'll have been married five years in the spring"
Curtis Hoffmann
My wife got a foot model to treat the muscle twitching caused by Parkinsonism. She used it for a few months, set fairly high. I tried it once to see what it was like, and man my legs got jerky. She gave up on it and it's been sitting under her desk ever since.
Charles Bruckner
As a young lad of 17 Injured both my knees and had to get surgery to repair the damage. And had to endure hours of physical therapy. They had a bench model of a TENS unit and it was still set up from the last patient and set quite high. Just as the PT Tech was attaching the last electrode to the unit , It was excruciating painful and I kicked another PT Tech right square in the bum. She was not very impressed and was about to give me a severe tongue lashing. It was explained that it wasn't intentional and I had no control over it. As swimming was a great way to get exercise I spent most of my time at the country club pool. Oh the amount of sympathy attention from the Young lifeguards was great. I forgot and didn't turn off my portable Tens unit and it was coiled up like a snake in the chair under a some wha moist towel. One of the hottest female lifeguards came by and sat down and as the water from her was soaking into the towel completing the circuit with her sensitive bits. She launched her self into the air and into the pool. I had lots of explaining to do.
Big Clive
It's extraordinary how little current is required to cause significant muscular contraction. Keep in mind that similar units are also caused to temporarily restrict the movement of the legs of cattle while they are being treated by vets.
Big Clive
Yeah - wait until you see the next video.... I'm totally going to get my wrists slapped by YouTube for that one.
Chris Parsons
I have a slightly more modern zapper like this, they are fairly effective for muscular pain relieve of tight muscles but not much beyond that. The thing that amazes me about mine is how long the battery charge lasts, months long usage from a single charge. The muscle stimulation can be set to the threshold of pain but I guess the current is so low that the actual power draw in minimal.
plasse
More like "booty" zapper