Great Educational Kit
For EMF Detector
I bought this kit mainly because I wanted a different type of easy soldering project than the usual digital clocks and blinking LEDs. It arrived very promptly in good anti-static packaging, and with a set of printed instructions that were easy to read and included the schematic. The resistors were bundled, which is nice when you are a beginner like me, and the PCB was very well marked and made it easy to understand the assembly. The plastic case is easy to assemble and is reasonably durable and attractive for the price.
After assembly, I powered my new detector up and investigated the sources mentioned in the manual. The background noise from the environment is moderately loud, but when I ran the detector over a laptop and smartphone screen I could easily hear the difference between the less active parts of the screen and the power couplings. My TV made a different, louder noise, and the tubes of my nixie clock and its 180V DC power supply were also very loud and very distinct. The transistors in the power supply are very high pitched and screaming sounding. I listened to a 110V surge protector to compare, and it had a much deeper tone and sounded like it was operating on a different frequency, I guess?
Overall, as a beginner to electrical circuitry, this kit has been very stimulating during assembly and during my novice investigations of electronic devices.