Ximimark 2Pcs Metal Detector Kit Electronic Soldering Practice Kit Non-Contact Sensor Board Module Electronic Part Metal Detector DIY DC 3V-5V 60mm

A great buy for practicing soldering and it is practical. I'll buy again for a larger project involving quite a few of these

0/8 purchased kits had the one required S9018 NPN transistor + two S9012 PNP transistors. Most kits had two transistors only usually NPNs. In addition 8/8 kits included one 4.7K ohm resistor (not required), but were all missing the one (required) 470 Ohm resistor. No instructions, no part orientation warnings for polarized capacitor, polarized LED, and polarized switch none of which (of course) are keyed. You must carefully place parts by (1) silkscreen hints (like silkscreen notch on switch), ground plane that connects to polarized capacitor (-), and LED anode must be identified from LED datasheet (not included). Does not include case, battery holder, mounting hardware or handles required for actual use. Purchased as gifts, but probably not worth the money when all issues are considered. CAVEAT EMPTOR indeed! No schematic diagram or explanation of circuit theory (a lost opportunity to inspire our overly video game addicted society; a shame really as this kind of kit is exactly what got me interested in Electrical Engineering many years ago. I do not yet know if it actually works, with 8 kits and not enough parts of the right kind to finish even one. I saw no way to simply get the parts I am missing from the vendor; sending the kits back is not worth the postage. AVOID.

My kids had a lot of fun assembling these metal detectors, but they don't really work.At best, there is a constant squeal and it changes pitch when it detects metal.YouTube videos confirm how they work. Worth the $5 but clearly not a usable metal detector.

Assembly took about 1 hour , with 1 resistor missing from kit, that I supplied myself. As there are no instructions care must be taken over the 2 different types of transisitors and the polarized components such as transistors, LED & electrolytics.The metal detector worked immediately and well, so for the price this is a good product but not something most kids could assemble correctly without assistance.

i built an automated robot with mapping abilities and programmed it to use metal detectors and search an area for items made of metal. they have proven very reliable

Kit is missing a 9012 transistor leaving one of the item useless.

Very useful metal detector to start making a big one. Good and affordable price!

This kit is poor. There are no instructions and the part values in mine don't match what is labeled on the silkscreen. It doesn't detect metal worth a hoot. I have to touch an object to the coil to get it to trigger but then it triggers on non-metal objects as well. They also made a poor choice for the transistor footprints, making it difficult to hand solder.