I am still drawing schematics of old transmit/receive VLF detectors that I am purchasing and am finding great similarity in them.
The goal is to acquire an understanding of the key sections of the signal flow and pick the best functional designs to incorporate into a micro nugget gold detector.
I may be striving for a circuit that I cannot develop without extensive electronic engineering background, but I have not smoked any Op Amps yet, and I suspect that Texas Instruments, Analog Devices, and many others have come up with some nice new chips with enhanced engineering specifications.
I must emphasize that this activity is purely for the understanding and achievement of a single detector for personal use to find very small native gold.
Without limitless funds to purchase and dissect newer (and still expensive!) used gold detectors I pose some questions here:
What are the best 'modern' op amps to employ and which for what sections of the circuit, or are oldies/goodies still prized?
For frequencies above 50KHz to 100KHz, where should I start, what window best avoids radio interferences?
Should I crystal lock the transmit oscillator and forcefully drive the transmit coil or should it be part of a resonant (Colpitts like) oscillator?
On good gold detectors of renown (Thank You David Johnson and All Others) are the coils the critical starting point?
In the medical laboratory world the terms sensitivity and specificity are used to statistically target bio-markers of disease.
Which one / or both would apply best to a good gold detector without a DSP (digital signal processor) to describe the action of discretely flagging a small target in a sea of 'ground' noise?
Sorry I don't know much about the actual detection phase of the circuits (an inverse or reversal of superheterodyned radio signals?).
Not visualizing how a good detector captures that little signal for snagging a quarter grain piece of wire gold in a heavily mineralized soil.
Makes me think of viewing the signal expansion option on my old Techtronics oscilloscopes.
If you capture an analog data stream of a single manual sweep of the detector head over the ground, pump it through an analog to digital converter and store it in a syndrome memory type loop maybe the little goldie bleeps could be filtered out from the back "ground" signals by masking them with a synced overlay of the averaged ground signal. OK, just guessing, probably already done years ago with 'ground' tracking feedback circuits.
If I were to start with a simple (maybe the wrong word) manual ground balance circuit, what would be the best low powered-on resistance CMOS switch available today to use or should I apply a FET, NMOS, BIMOS, ect to pick-off the receive signal?
I am guessing that better techniques are being employed now via code/compiled software. If so which language is best for application to this type of signal processing? Whats simple without purchasing an expensive development system.
If coding should I employ fuzzy logic format neural net or a straight recursive feed back type iterations process?
Right now just trying to get some analog hardware to bark for gold bits.
Like my friend's (Musk Mobile) Tesla car, something gets lost in the driving-detecting experience when it is filtered through eleven high powered graphics processors.
For core hardware should I just slam all ideas through a SPICE program (circuit development and test program) and keep all those noisy little antennas on the breadboard at bay?
Again this is about understanding more than show n tell of what I found on the weekend; though that would be a nice 'proof of theory' validation.
I think we all would like to pay for gas to and from 'the diggens' or just buy a new truck with the finds.
OK, toooo many questions I know; these are just starters.
Many of you have great wisdom in this field of endeavor and recreation.
I most appreciate any ideas. I am just starting, year one.
Thanks.
The goal is to acquire an understanding of the key sections of the signal flow and pick the best functional designs to incorporate into a micro nugget gold detector.
I may be striving for a circuit that I cannot develop without extensive electronic engineering background, but I have not smoked any Op Amps yet, and I suspect that Texas Instruments, Analog Devices, and many others have come up with some nice new chips with enhanced engineering specifications.
I must emphasize that this activity is purely for the understanding and achievement of a single detector for personal use to find very small native gold.
Without limitless funds to purchase and dissect newer (and still expensive!) used gold detectors I pose some questions here:
What are the best 'modern' op amps to employ and which for what sections of the circuit, or are oldies/goodies still prized?
For frequencies above 50KHz to 100KHz, where should I start, what window best avoids radio interferences?
Should I crystal lock the transmit oscillator and forcefully drive the transmit coil or should it be part of a resonant (Colpitts like) oscillator?
On good gold detectors of renown (Thank You David Johnson and All Others) are the coils the critical starting point?
In the medical laboratory world the terms sensitivity and specificity are used to statistically target bio-markers of disease.
Which one / or both would apply best to a good gold detector without a DSP (digital signal processor) to describe the action of discretely flagging a small target in a sea of 'ground' noise?
Sorry I don't know much about the actual detection phase of the circuits (an inverse or reversal of superheterodyned radio signals?).
Not visualizing how a good detector captures that little signal for snagging a quarter grain piece of wire gold in a heavily mineralized soil.
Makes me think of viewing the signal expansion option on my old Techtronics oscilloscopes.
If you capture an analog data stream of a single manual sweep of the detector head over the ground, pump it through an analog to digital converter and store it in a syndrome memory type loop maybe the little goldie bleeps could be filtered out from the back "ground" signals by masking them with a synced overlay of the averaged ground signal. OK, just guessing, probably already done years ago with 'ground' tracking feedback circuits.
If I were to start with a simple (maybe the wrong word) manual ground balance circuit, what would be the best low powered-on resistance CMOS switch available today to use or should I apply a FET, NMOS, BIMOS, ect to pick-off the receive signal?
I am guessing that better techniques are being employed now via code/compiled software. If so which language is best for application to this type of signal processing? Whats simple without purchasing an expensive development system.
If coding should I employ fuzzy logic format neural net or a straight recursive feed back type iterations process?
Right now just trying to get some analog hardware to bark for gold bits.
Like my friend's (Musk Mobile) Tesla car, something gets lost in the driving-detecting experience when it is filtered through eleven high powered graphics processors.
For core hardware should I just slam all ideas through a SPICE program (circuit development and test program) and keep all those noisy little antennas on the breadboard at bay?
Again this is about understanding more than show n tell of what I found on the weekend; though that would be a nice 'proof of theory' validation.
I think we all would like to pay for gas to and from 'the diggens' or just buy a new truck with the finds.
OK, toooo many questions I know; these are just starters.
Many of you have great wisdom in this field of endeavor and recreation.
I most appreciate any ideas. I am just starting, year one.
Thanks.