Jason in Enid
Elite Member
Yes. That post is 2 years old, there has been a lot of water under the bridge since then. A well known EE has done extensive testing of the EMF of the FBS detectors. I can't post a link to it because it's on a competing forum, but if you search for "barnacle bill fbs minelab" you should be able to find it.
He goes into way more detail than I can but the basis of the FBS is multiple freq square wave pulses with multi-period sampling of the return which allows it to read dozens of harmonic off a series of base frequencies. those base frequencies can be automatically shifted to compensate for current conditions.
All other VLF detectors use frequency sampling and comparison for target ID. That is why cranking up the disc knob causes a loss of depth, it is changing the baseline it compares the target return against. FBS detectors don't change the baseline. When you add more disc, it simply looks at "do I alert or not alert on that return".
Minelab STILL hasn't patented their FBS technology so that others can't steal it, because we all know china will steal anything it can copy for a profit and nobody stops them. Even though the basics of how FBS works has been worked out, the coding that allows it to be stable and effective are still a company secret.
Edit to add - also search for posts about FBS by NASA Tom. HE also has a very good, in depth explanation of FBS functions.
Last edited:
