FBS Air-Test?

[seahunter34]

What's the story here? I do not have much experience with FBS machines and would like to know more on air-testing. Do FBS detectors air-test well? I ask because in 1 book about BBS machines is says not to be discouraged with poor air-test results, because BBS detectors need to see the ground... where they really perform. So, FBS must be similar to BBS machines? Yet in another book on FBS machines I read... with FBS detectors what you get in an air-test you also get in the ground. This would imply that air-testing an Explorer demonstrates how deep one might expect to find that particular target in the ground? But then why do BBS machines give poor air-tests and need to see the ground matrix and not FBS machines? I've read this stuff about BBS/FBS machines in other places too and wonder if others are just repeating what they read? There seems to be a contradiction of sorts here?

Then adding to the mix, I'm told by those in the know that Explorers do not like the air gap/space above targets buried in the ground and/or, FBS machines do not like soft soils or recently disturbed ground. This also seems to contradict what Explorers can see in the air, so can they in the dirt?

I did a little test last night air-testing a larger gold ring. With machines just on the edge of stability I air-tested 2 detectors on that ring for a solid response. My Garrett AT Pro with 8.5X11 DD coil and my Explorer XS with Pro Coil. The AT Pro gave a remarkable solid signal response to 16 inches! Possibly slightly beyond. My XS Pro Coil combo only to about 13 inches for the same signal response quality as the ATP. Now I'm pretty certain the AT Pro would not hit the ring buried 16 inches deep in dirt. But would the XS hit the ring buried 13 inches? The same distance as the air-test? Or perhaps even deeper in the ground?

When I saw just how sensitive my Garrett was to the ring, got me thinking about this.

 

[dewcon4414]

Sounds like you been talking to the right people. They go deeper in the ground that in the air. They do NOT like space between the coil and soil unlike say a Fisher F75. Until you put the coil on the ground in your neck of the woods you cant count on air testing. The FBS machines handle bad soil remarkably well... they just dont care much for iron.... they love to hang especially with to much sensitivity and a lot of targets. You will find if you have say moles hole dirt they will false a bit. As far as the gold ring the large ones are easy... its the small ones when you add minerals or salt that may be an issue. If you are using a Pro coil your detector is attempting to process approximately 7 gallon of soil.... depends on whats in the soil. Some targets will mask the ring if deep and in close proximity. 13 inches..... easy answer NO. Bryce is about as good an anyone ... the deepest silver coin hes mentioned digging is around 11 inches in mineralized soil..... the ring doesnt have that kind of conductivity. Every machine has its short comings.... thats why you select the right machine for the targets you intend to hunt.

Dew

 

[seahunter34]

My XS easily hits a quarter buried 11-12 inches (6 months now) in Hot ground. My AT Pro with several inches of air to spare and that's at 15 kHz! I would sure hope Explorers can hit silver coins beyond 11 inches? Because the ATP can! Unless they're on edge with trash? I laid my quarter flat in the hole, but feel it might have shifted over time, because it's tougher to hit now. In the L-Treasure SE Pro field test a gold ring was found some 10-11 inches! I've been told some FBS users hit silver targets 18-20 inches in wet salt sand with the Pro Coil!

I didn't know FBS machines processed/track the coil ground volume continually. I thought they took kind of a snapshot of the ground matrix, then ignored it? That's why some imply FBS can see as deep in the ground as in the air? Again though, that would contradict that FBS needs to see the ground for depth? So I wonder which is it? I suppose I could air-test a gold ring and a silver coin of similar size at a beach, then see how deep I can hit then in wet/dry sand? My beaches are pretty hot, so this would not be a cake-walk!

 

[dewcon4414]

18 to 20 inches.... id have to be there to see that even on a beach thats deeper than i believe possible. 14 to16 inch id say is possible. Ive seen people dig targets and on the last BIG scoop the target was close to the top..... but they measure the hole. I suggest you do your own testing and prove it to yourself like you said on wet and dry sand. Comes down to your ability to use the machine as to what it may or may not do.

Dew