Eisco Labs - Demonstration Electroscope - Detect & Measure Static Electric Charge - 10.6" x 6.3" x 4.7" - Science Experiment Tool for Physics, Chemistry, and Educational Use

I bought all three electroscopes on amazon and this is by far the easiest and most useful. The other two both require you to mount a thin strip that is used as the indicator, and in both cases mounting this strip is a big hassle and the resulting assembly does not work very well. This scope works out of the box, and works perfectly. The readings are sensitive and reproducible.

My only complaint is that the manufacturer directly markets to teachers, and so the version that I received came with no instructions, and the manufacturer wouldn't even let me download a pdf copy of the instructions unless I proved to them that I was a teacher. Knuckle-head company, but it's a good product. Thankfully there is so much material online for how these things work, it was no problem.

I can charge it the normal way with rods and cloth but it seems it should beable to charge with a power supply but I get 0V across the device. I probably have to sand it or something but instructions would be nice. I hear that they only give instructions to teachers which is absurd.

Okay, but it lacks sensitivity.

If you've only ever used the foil-type electroscopes (the kind that usually come in a chemistry flask), you have no idea how great these can be. The solid needle does what it's supposed to do every time. Perfect for demos on charging by conduction, polarization, and induction, and it's big enough that my kids can see it at the front of the class. The price is hard to beat as well. Similar products in educational supply catalogues go for at least twice as much. If you're looking at this vs. the ones that are totally enclosed with glass, stick with this one.

It works very well and because of its design it is much more responsive and linear than most electroscope designs. I therefore attached a suitably sized protractor to mine to make it into a quantitative instrument.

I read the many positive reviews for this item and decided to purchase it. But I am very disappointed because the device seems quite insensitive. Occasionally I find that the clothes I wear generate a lot of static charge -- I can tell from the crackling sound and the tendency of the clothes to cling to the body. At such time, I touch this device and expect to see some reaction -- but alas nothing happens. For all practical purposes, this device seems purely ornamental. I would have returned the item -- but it looks like the return period had passed by the time I decided this item to be of no use at all.

Bought as a demonstration for my physical science class. My 8th graders really enjoyed it. It did not come with instructions and have to be a teacher to register on the site to get them.