Equinox 600 Vs Fisher F44 & F70

[Jeff McClendon]

6 hours ago, WV CoinMiner said:

No, we can’t, since it’s not true. Why would a guy with so much background perpetuate this old myth? By Steve H

I got this email and am looking for the post, must have been deleted.

What myth are you referring to here? 

 

I'll give an answer about the myth that Steve H was referring to. These are not my words since I just use metal detectors and don't want to worry about who regulates what. These two quotes come from Carl Moreland, AKA Carl NC on some forums, he's Geotech on this forum and he also has the Geotech Forum.

Carl NC @Geotech

"Actually, FCC regs start at 9kHz. Above 9kHz there are radiation limits, but they are spec'd as an electric field gradient and detectors transmit a magnetic field, not an electric field. For all practical purposes, there is no FCC reg that limits detector field strength."

Carl was then asked a question.

 Question: I believe that the problem with increasing output power (measured in watts or in the case of detectors milliwatts) is that the signal from the ground gets stronger faster than the signal from targets and so if you put out too much power then the ground drowns out the target signal..........?

Carl answered:

"This is exactly right. It's a balance between TGR (target-to-ground ratio) and battery life. Even without the ground signal, it takes a theoretical 64x more transmit signal to get twice the target depth. Instead of a 10 hour battery life, vou would have 10 minutes."

Hope that answers your question about the government regulation "Myth".

 I also hope it once again substantiates Steve’s statement that the ground itself is the most important factor in VLF and pulse induction metal detecting. Having a detector one knows well is important but not as important as the ground itself. 

[Guest WV CoinMiner]

Still regulated to 5watts by FCC which gives about 96.75% peak the gains after that come at a cost of battery life. Yes new battery technology is coming and material like graphene will probably be used outside my expertise. But it is not a myth of 5 watt regulation same as CB's. I'm going back to watching for deer to come by the tree stand, I have my winter hobbies too.

[Chase Goldman]

5 hours ago, WV CoinMiner said:

Glad you explained the Tarsacci, yes Deus was and still is a great product and having used Deus 2 it is an upgrade. Experience I have and my experience has taught that one can take a 1983 Tesoro Saber and still find coins behind other machines and vice versa. Yes target id my have helped with processors but your eye are still the best discriminatory "Monte" and by that he definitely meant you don't truly 100% know what it is until it's recovered because every machine averages and sends the ID accordingly for you to decern

Yes.  It's 100% only when you have the target in hand.

[phrunt]

It's a shame the USA is the only country on the planet, and has the only regulations that govern the worlds metal detectors performance attributes, if only there were other countries and other manufacturers outside of USA that didn't have to concern themselves with FCC regulations as they had their own governing bodies to set their own rules.   There are manufacturers of metal detectors in some countries that aren't known to follow rules, they should pump up their detectors and blow the world away with the performance increases they can get on their largely cloned models which I'm sure they would do it gather up as many sales as they could.

Sounds to me like a simple solution this this wild theory would be to cut out the US market and sell superior detectors not limited by FCC regulations to the rest of the world, you know the even larger number of people that live in other countries and have these super detectors not hindered by the FCC.  Or even release a "US" version that is a cut back limited edition while the rest of the world could use these super high powered not FCC restricted detectors 🙂

So much disinformation in this thread.

 

[Digalicious]

That was epic, "right on the mark" sarcasm Phrunt!

 

[Chase Goldman]

2 hours ago, WV CoinMiner said:

Still regulated to 5watts by FCC which gives about 96.75% peak the gains after that come at a cost of battery life. Yes new battery technology is coming and material like graphene will probably be used outside my expertise. But it is not a myth of 5 watt regulation same as CB's. I'm going back to watching for deer to come by the tree stand, I have my winter hobbies too.

Again, as Jeff pointed out by professional metal detector designer Carl Moreland (he's cowritten several books on the subject and has been employed as a lead design engineer by at least two major US metal detector manufacturers) that limit does apply to the metal detector electromagnetic field power emitted by the coil (at frequencies above 9 khz) but the coils don't come anywhere close to that limit regardless of frequency.

Carl Moreland in response to a question on why metal detector manufacturers don't advertise the power output of metal detector transmit coils:

"Because it's a meaningless number. A metal detector develops an alternating magnetic field by putting an alternating current through a coil of wire. Ideally, there is no "power" because inductors don't dissipate power, and there is no signal "transmitted" as with a radio. There is power consumed by the transmit circuitry, but that depends on the design of the circuit. If I resonate the transmit coil my power consumption drops significantly, but the magnetic field can be the same strength as an inefficient circuit that only sucks down more battery current. Would you pay extra for a less efficient design just because it has a higher "power" output?"

This quote makes me smile when I think about all the ridiculous hoopla surrounding ML's claims of 50% more power to the coil.  Anyway...the key here is contrary to popular belief, a metal detector is NOT a radio transmitter.

The 5 watt limit does apply to some unlicensed personal communications devices (GMRS, FRS, CB and other similar radio transmitters IN THE US only).  As we know, metal detectors only available outside of the US do not perform appreciably better than those sold in the US that have to comply with FCC regs.  That's because physics not arbitrary power limits in the US or elsewhere are determining the highest practical coil power limits.

Metal detector manufacturers do also have to meet US and European and other international power regulations for the wireless BT and similar radios embedded in their detectors to provide wireless audio transmission, but again, this has no impact on coil transmission power or emissions.  That's why you see FCC and European compliance documentation associated with metal detectors.  They also have to specify the power output in dBm across the frequency spectrum for which they transmit.  Some confuse these radio certifications with coil output power compliance  (See example data sheet from the Minelab, below).

To put those numbers in perspective:

0 dBm = 0.001 watt

8.9 dBm (the power output of the GoFind BT radio) = 0.008 watt

and -30dBm, the total transmit coil spectrum power ALL Minelab detectors remain below is 0.000001 watt.

None of these are anywhere close to the 5 watt FCC limit.  So you could increase the coil output power by a factor of 5 million and still not exceed the 5 watt limit.

Finally, present battery technology and efficiencies are not limiting detector output power nor does it have anything to do with FCC limits, either.  Batteries are limiting continuous run time, but with run times exceeding 10 to 12 continuous hours or more, they are not really practically hindering anything. 

So hopefully, this myth is pretty much busted.  (But something tells me we won't hear the last of it, unfortunately)...

Anyway, hope you bag one out there.  Enjoy your hunt...

 

[Guest WV CoinMiner]

16 minutes ago, Chase Goldman said:

Again, as Jeff pointed out by professional metal detector designer Carl Moreland (he's cowritten several books on the subject and has been employed as a lead design engineer by at least two major US metal detector manufacturers) that limit does apply to the metal detector electromagnetic field power emitted by the coil (at frequencies above 9 khz) but the coils don't come anywhere close to that limit regardless of frequency.

Carl Moreland in response to a question on why metal detector manufacturers don't advertise the power output of metal detector transmit coils:

"Because it's a meaningless number. A metal detector develops an alternating magnetic field by putting an alternating current through a coil of wire. Ideally, there is no "power" because inductors don't dissipate power, and there is no signal "transmitted" as with a radio. There is power consumed by the transmit circuitry, but that depends on the design of the circuit. If I resonate the transmit coil my power consumption drops significantly, but the magnetic field can be the same strength as an inefficient circuit that only sucks down more battery current. Would you pay extra for a less efficient design just because it has a higher "power" output?"

This quote makes me smile when I think about all the ridiculous hoopla surrounding ML's claims of 50% more power to the coil.  Anyway...

The 5 watt limit does apply to some unlicensed personal communications devices (GMRS, FRS, CB and other similar radio transmitters IN THE US only).  As we know, metal detectors only available outside of the US do not perform appreciably better than those sold in the US that have to comply with FCC regs.  That's because physics not arbitrary power limits in the US or elsewhere are determining the highest practical coil power limits.

Metal detector manufacturers do also have to meet US and European and other international power regulations for the wireless BT and similar radios embedded in their detectors to provide wireless audio transmission, but again, this has no impact on coil transmission power or emissions.  That's why you see FCC and European compliance documentation associated with metal detectors.  They also have to specify the power output in dBm across the frequency spectrum for which they transmit.  Some confuse these radio certifications with coil output power compliance  (See example data sheet from the Minelab, below).

To put those numbers in perspective:

0 dBm = 0.001 watt

8.9 dBm (the power output of the GoFind BT radio) = 0.008 watt

and -30dBm, the total transmit coil spectrum power ALL Minelab detectors remain below is 0.000001 watt.

None of these are anywhere close to the 5 watt FCC limit.  So you could increase the coil output power by a factor of 5 million and still not exceed the 5 watt limit.

Finally, present battery technology and efficiencies are not limiting detector output power nor does it have anything to do with FCC limits, either.  Batteries are limiting continuous run time, but with run times exceeding 10 to 12 continuous hours or more, they are not really practically hindering anything. 

So hopefully, this myth is pretty much busted.  (But something tells me we won't hear the last of it, unfortunately)...

Anyway, hope you bag one out there.  Enjoy your hunt...

 

Again didn't argue that, just said it was an FCC Regulation

[phrunt]

I believe all anyone was trying to do was get the point across to you that the FCC regulations are not limiting detector performance, and if they were manufacturers like Rutus which make fantastic multi frequency detectors and many other manufacturers in other countries such as Bulgaria and even and especially China would be taking advantage of it seeing they don't even sell into the USA which is bound by these regulations.

[Guest WV CoinMiner]

Like anything with limits contains you in a box and you must work within that parameter. No one is going to do R&D if they can't sale it. I wasn't arguing gains after a certain watt, that never left my lips. Just stated the fact there is a government reg concerning it.

[Chase Goldman]

3 hours ago, WV CoinMiner said:

Again didn't argue that, just said it was an FCC Regulation

Just responded because you kept referring to it as if it were relevant to your earlier statement that FCC regs are somehow limiting detector performance and development and the myth has a life of its own, you are not the only one but simply the latest one to resurrect it.  

Getting the technical truth out there was also not about bashing you or anyone else.  It's about educating folks (anyone who comes here to learn and share) so they can be better detectorists.  Again, you posted something as technical fact.  You were right about the regulation but not how it impacted or applied to detectors. It not a requirement that you know how the tool works but it certainly doesn't hurt.  

I agree that sarcasm just ratchets up the vitriol, and tried to avoid it.

Regardless, setting the record straight with clarity and facts does not warrant attacks and name calling in reply...