true or false

if I'm not mistaken.

•time-domain .....means PI technology
•square-wave ....means multi-frequency technology
•sine wave ........means VLF technology

Hi,,False........JJ

•time-domain .....means PI technology (yes)
•square-wave ....means VLF multi-frequency technology (with digital processing; I don't believe analog circuits can deconstruct the response from such an 'artificial' waveform. A pure square wave consists of an infinite number of sine waves of various amplitudes and frequencies.)
•sine wave ........means VLF technology (with analog or digital processing; all analog machines work with one or more sine waves)

Tom?

Good reference here: [humanise.info]

... and one interesting line from the source: "It is possible to have a metal detector that uses both Pulse Induction and Frequency Domain techniques at the same time. One or several patents exist on this."

Time domain can be PI or VLF, in the case of FBS (and thus most likely FBS2)
(Complex) square wave is what current FBS units transmit. Processing doesn't have to be digital (Fisher CZ's did analog processing) though these days it would likely be done digitally.
Sine-wave implies VLF.

"> Time domain can be PI or VLF, in the case of FBS
> (and thus most likely FBS2)"
If this end up being true, then the new machine will be a must have tool. I've actually got some areas where a regular machine shuts down because of the coal slack waste in the ground.



Pimento Wrote:
-------------------------------------------------------
> Time domain can be PI or VLF, in the case of FBS
> (and thus most likely FBS2)
> (Complex) square wave is what current FBS units
> transmit. Processing doesn't have to be digital
> (Fisher CZ's did analog processing) though these
> days it would likely be done digitally.
> Sine-wave implies VLF.

Sometimes advertising semantics/words can be used out-of-context. Sometimes the definition of one base-platform operating-system (ie "time-domain" ) encroaches ......... close to,, or into ......... another operating-system definition.

For example: sine wave = ONE of the many tools used to measure sine waves is 'time'. Hence/thus ........... are we allowed to categorize this as a form of domain with time? In the purist of definition form: NO! Absolutely not. Yet....... waters become more cloudy ......... when someone 'blends' two separate operating-system forms together.

Another (more direct) example. Many Pulse Induction (PI) units operate in the VLF range. Yet, when we say our metal detector is a "VLF" ...... this is a misnomer. What NEEDS to be said is: my metal detector is a IB (Induction Balance). It (most probably) operates if the VLF frequency range.
VLF is a frequency range............ and NOT a operating-system.
A PI can be VLF
A IB can be VLF

It is fun and exciting to see a new metal detector on the horizon ........... soon to be released............... and the symantics thereof; as to what the unit is ............ so we all have something to "speculate" on/about.
BUT............. the real answer comes in its truest form as to: HOW WELL DOES IT REALLY PERFORM IN THE REAL-WORLD. Ad's, hype, semantics, colorful photos of gold coins/rings, speculation, human emotions, dreams etc.....................
I see/witness this EVERY time! (((Welcome to being human))).
Yet................. the bottom-line.............. once again................. HOW WELL DOES IT PERFORM IN THE REAL-WORLD.

THEN .............. we still need to differentiate between the 'biased' folks who post (for financial gain or other reasons) vs. . . . . what is the true reality!

(((((( Hence, my required scientific approach methodology ))))))



Edited 1 time(s). Last edit at 05/05/2012 02:21PM by NASA-Tom.

Might make a copy of Tom's last post as thats the way it is with new units on the horizon and hitting the bricks....As newer, faster, bigger, deeper etc. doesn't neccesarily make it better and certainly the proof is in the pudding...

Still amazes me to see so much outwardly expressed "hate/frustration/anger" ........................... or ............................ "love/bias/excitement"
-
-
on something that is not yet released; subsequently we know nearly nothing about (yet).

Once again: Welcome to being human!

--------------------------------------------------------


Then.............. when the device is finally released: Commence the oceans of 'opinions'.

From my rainy day musings I think we have to add SPECTRUM ANALYSIS to metal detecting terminology. From what I have read, seen and measured, Minelabs' FBS technique is to determine where in the the frequency spectrum a received target signal falls to determine its conductivity value. Reading some of the recent patents by Mr. Candy suggests that FBS2 may have the capability to shift the transmitted signal frequency to enhance the response of desired target signals.
Whites V3i uses its Spectragraph display to show the targets response to 3 different frequencies. Sort of a manual spectrum analysis. Minelab seems to have taken this many steps further with FBS(2).


But then again, who knows? It's fun to speculate though.

Posted on my favorite MD forum today by Digger, one of Minelabs beta testers, answering the question how the CTX can identify multiple targets simulataneously:

Quote
Digger
The CTX 3030 is an FBS2 detector, not VLF. VLF (Very Low Frequency) detectors transmit a single frequency (typically less than 30 kHz) sine wave. VLF detectors analyze signals based on response to a given frequency. FBS (Full Band Spectrum) detectors transmit a wave form (1.5kHz - 100 kHz) comprised of multi-period rectangular waves. FBS technology analyzes signals with reference to time, not frequency. By implementing signals using multiple frequencies in relation to time, FBS technology allows for improved discrimination by analyzing both ferrous and non-ferrous properties. For more details on FBS technology, read this article by MInelab's Bruce Candy, the man who invented it. Metal detector - Basics and Theory by Bruce Candy [www.minelab.com]

[www.findmall.com]

Minelab seems to have developed an entire alphabet soup of new acronyms to describe their digital software algorithms used to process complex VLF signals. The phase shifting of respective sine waves (transmit vs. receive) is what gives VLF machines the ability to discriminate. Candy describes this in detail in many of his patents as a basis for introducing his new software algorithms. But only a PI unit really works in the time domain where the resultant eddy currents in the detected target decay at a slower rate compared to the sudden collapse of the original transmit signal and the resultant is measured over time. PI units units run in the 100 to 1000 Hz range, but don't have a phase shift component to analyze as in a VFL, inductive balanced machine. Diggers response above in no way answers the original question. The follow-up responses are just typical Findmall boot licking when it is obvious that further critical questions will be deleted.

- Minelab rebrands its PI technology as MPS (Multi Period Sensing).

- Minelab markets its VLF as VFLEX.

It's interesting to note that the CTX amplifies the received signal at the coil and appears to do an A/D conversion there before sending the digitized signal back up the shaft.

I look forward to learning more of this "FBS2" technology, minus the legal patent jargon and the candy coated marketing nonsense describing the CTX 3030 so far.. The Bruce Candy link referenced above is interesting nonetheless.



Edited 1 time(s). Last edit at 05/14/2012 02:29AM by go-rebels.