Everyone here with a bit of electronic knowledge knows how to make an LRL. In fact some LRL commercial products have shown that no electronic knowledge at all is needed, since the electronic aspect is entirely bogus and therefore nothing has to actually work. In the case of at least one well-known LRL, the only thing electronic was the advertising claim: investigation revealed no actual electronics, not even non-functional electronics.
In short, anyone who knows what an LRL is, knows how to make one. All it takes is a wire coat hanger, a transistor ripped out of a junk radio, and two inches of scotch tape. To sell it, however, means you have to put a lot of lipstick on that pig and then stand her on a street corner, and not everyone knows how to put thousands of dollars worth of lipstick on a $1 pig much less how to stand her on a street corner.
At least two people who post here are engineers for well-known companies that manufacture electronic locating apparatus, including both metal detectors, and apparatus capable of locating at a distance. To design an LRL and get it into production would be real easy, but there's this problem: the damn things are frauds. Marketing department is used to selling stuff that works, and can't figure out how to sell a product that's outright fraudulent. And if they do understand how to market LRL's, even so, they don't want fraudulent stuff mixed with the real stuff ruining its reputation.
There are manufacturers who mix real stuff with fraudulent stuff, for example OKM. An examination of their (presumably) real stuff shows how LRL's have influenced their overall business strategy. Over the long haul they're going to have to stop ruining their reputation on the real stuff by getting rid of the LRL products.
It sure would be fun to have their engineers posting here...... !! But I predict no designer of real stuff wants to be seen in public defending LRL's.
