I am not seeing good depth in air tests of my pi, pi pro, and DF. Some guys are in love with their PI machines because of the deep targets they get. So it appears that some machines are deeper than others (proven in some videos). I don’t see the reasoning that if I get lousy depth in an air test I’ll get better if the target’s in ground. Maybe for those halo targets but not for fresh drops or recent storms. Thoughts?
Pi depth and reality
- Thread starter Bklein
- Start date
Surf Master
Forum Supporter
The Administrator
Said the pi's don't air test well in one of his post, my DF is deep, never air tested it , he ran a DF for year's , i believe him, he will most likely chime in , happy hunting.
Said the pi's don't air test well in one of his post, my DF is deep, never air tested it , he ran a DF for year's , i believe him, he will most likely chime in , happy hunting.
OnTheBeach
New Member
- Joined
- May 30, 2018
- Messages
- 15
https://metaldetectingforum.com/showpost.php?p=1244267&postcount=5
With the coil horizontal my DF seems to max out at around 16" on a medium size 14kt band when air testing. I think voltage matters with this coil. The unit will still work at 9 or 10 volts but it will see deeper targets at 12 or 13 volts for example. Just my opinion.
With the coil horizontal my DF seems to max out at around 16" on a medium size 14kt band when air testing. I think voltage matters with this coil. The unit will still work at 9 or 10 volts but it will see deeper targets at 12 or 13 volts for example. Just my opinion.
I see Earl responded.. I told him last week that air testing a pulse is a waste of time.. its why they see thru the salt and minerals that is important. They are deep. your PI PRO was my favorite PI that I owned..
If mine could do that I’d be happy. My Pi pro and DF seem to have the same pcb, same performance, same battery, and same tx transistor IRF9460. Could you send me a photo of your pcb?
Thanks for the link, I’ll have to read through it. I was testing vertical. I’ll give it another try. I seem to recall the lousy performing tests on YouTube were vertical too.
Thanks for the link, I’ll have to read through it. I was testing vertical. I’ll give it another try. I seem to recall the lousy performing tests on YouTube were vertical too.
On white sand that isn't mineralized, PI depth advantage isn't that big. It is when you get into bad ground (black sand), the VLF machines lose a lot of depth, and PI machines don't.
DaviDs
Forum Supporter
^^^ 100%
DaviDs
Forum Supporter
I've performed hundreds of tests in wet, salt-water beach sand. No doubt, most PI setups are significantly deeper than single frequency VLF and noticeably deeper than Multi frequency VLF. Coil size also impacts depth.
Search my old posts and you'll find some of the data from my tests. Most tests used gold, silver and a quarter buried flat. Again, this is in wet, moist sand at an ocean beach. As best as I can recall, here are some approx depths with a quarter.
SF VLF - Bounty Hunter Jr - 5"
SF VLF - Garrett Carrot - 4"
SF VLF - ATP stock coil - 6"
SF VLF - ATP Detech 13" coil - 9"
SF VLF - Makro Racer 2 11 coil - 9"
SF VLF - XP Deus - 9"
MF VLF - Fisher CZ7 8" coil - 8"
MF VLF - Fisher CZ6 (NASA Tom tuned) 10" coil - 14"
MF VLF - ML Explorer 11" coil - 12"
MF VLF - ML Explorer WOT 15" coil - 18"
MF VLF - ML Explorer D/D 24" coil - 22"
MF VLF - ML Quattro 8" coil - 10"
MF VLF - ML Safari 11" coil - 14"
MF VLF - CTX 11" coil - 12"
MF VLF - CTX 17" coil - 18"
MF VLF - Excal 11" coil - 15"
MF VLF - Excal D/D 15" coil - 20"
MF VLF - NOX 11" coil - 12"
PI - Sea Hunter XL500 - 12" (air test was like 3-4")
PI - Sea Hunter MK2 8" coil - 14"
PI - Sea Hunter MK2 14" coil - 26" (air test was maybe 8")
PI - Whites Surf PI PRO - 18" (air test was maybe 8")
PI - Whites TDI - 24"
PI - DetectorPRo Pulse - 14" (air test was around 6")
^^^Keep in mind, these types of numbers are from a "test." I knew where the quarter was buried. I could tweak and change settings until I got an irradict or faint signal. By no means does it prove anyone can get these depths in a real hunt....but it is plausible.
Tom_in_CA
Elite Member
- Joined
- Dec 23, 2013
- Messages
- 20,753
Good comments so far, on the air-test vs real-ground test differences.
I would add this : Way back when, (1980s and '90s), when the first dedicated beach pulse machines began to appear on the market, they were getting deeper on the beaches, than standard machines were . Albeit with the inherent drawback of no iron disc. But as the years progressed, there are now plenty of standard discriminating machines where the depth is not much different.
Eg.: a CTX or CZ or Excal or Sov, etc.... versus most beach pulse = no difference in depth. It didn't used to be that way. In the old days, standard machines were at a few inches loss.
The only exceptions would be certain high powered nugget type pulse machines, where .... sure .... you could get a coin to 1.5 ft. deep ! (but that's too dang squirrely for my blood, haha)
I would add this : Way back when, (1980s and '90s), when the first dedicated beach pulse machines began to appear on the market, they were getting deeper on the beaches, than standard machines were . Albeit with the inherent drawback of no iron disc. But as the years progressed, there are now plenty of standard discriminating machines where the depth is not much different.
Eg.: a CTX or CZ or Excal or Sov, etc.... versus most beach pulse = no difference in depth. It didn't used to be that way. In the old days, standard machines were at a few inches loss.
The only exceptions would be certain high powered nugget type pulse machines, where .... sure .... you could get a coin to 1.5 ft. deep ! (but that's too dang squirrely for my blood, haha)
Aquaman
Elite Member
brncofan
Elite Member
TDI power baby ill never sell my TDI pro ive found some deep stuff 
Sandcrab
Elite Member
That is some of the best info I have seen on here... Even though is just testing, still gives an honest thumbnail. A tip of the hat to you.
If you would ever want more info on certain machines, especially when using different coils and how they compare, holler. Was an eye opener what a different coil could do... Especially when looking for a "certain" target...
That was the issue i always had. My part of Florida, i thought every PI i bought was a dud since my VLF's went about as deep. Except maybe on bobbie pins
Fixing to sell off a couple detectors and some gold to try the new Whites and the Fisher when it comes out though.
I went back to the beach yesterday and see what is happening. It is simply that the Pi’s are less sensitive to the ring on edge than the others. I kinda knew that when I pull the ring up with the string it would turn vertical, but proved this was it after placing the ring horizontally at various depths. The Pi’s will detect it in the 10-12” range. The testing still favors the CTX and GP Extreme though by a noticeable margin.
You need to stop making hunting with a PI some complicated..
If you are listening only for good beeps or tones then you will miss targets... I hunted exclusively with a pulse when I started out and nothing that had disc could touch its depth...
With the PI I listen for the deepest targets which don't even give you a tone they are a threshold break and nothing more..
Sandcrab
Elite Member
Since you have tinkered with your pulse machines and did not say if they were scoped/tested or not, your testing means nothing... Didn't you buy one that needed repair?
What is a noticeable margin???
The DF needing repair was needing a new coil due to the cable cracking. I cut it off and sent it to Whites for a total refurb with new coil. Then I put a new cable on the old coil. So I have two functional and pretty much identical DF coils. All my Pi’s at this point are stock configuration.
The CTX would detect the ring at 16”. However due to frustration with random waves that would come and thrash me I did not retest the CTX. Could next time in two weeks...
My criteria for detection is a whimper on the Pi’s, not a threshold break. There is a pretty small distance difference between a whimper and a solid tone - like 1-2”. To hunt by threshold break really makes me think the design needs to be changed to a VCO output where any target sensing bumps the frequency up - but maybe that’s just me.
The CTX would detect the ring at 16”. However due to frustration with random waves that would come and thrash me I did not retest the CTX. Could next time in two weeks...
My criteria for detection is a whimper on the Pi’s, not a threshold break. There is a pretty small distance difference between a whimper and a solid tone - like 1-2”. To hunt by threshold break really makes me think the design needs to be changed to a VCO output where any target sensing bumps the frequency up - but maybe that’s just me.
