Black Sand vs. New PI Detector

[Goldak]

Yesterday we were in San Diego (La Jolla) so I got a few hours to try the new detector in some pretty heavy "black sand". The whole beach was flat as a pancake and there must have been 50-100 yards of exposed sand at low tide.

The last time I was here I couldn't even use my Fisher 1220-x due to constant falsing. The Surf PI Pro definitely was affected by the high black sand concentration but I was at least able to back off on the gain control enough to work the area without losing all my depth. However, my depth was still impacted significantly, perhaps by 30% or so.

I got signals all over the beach although I really had to concentrate more to pick them out. With a lot of nails in the area I got more practice listening for those double beeps that kind of act as discriminating sounds. Maybe someone here can tell me if those double beeps are ever anything good like chains or other types of jewelry. Do you PI users dig the double beeps?

As challenging as it was working this beach, I think that it might be a good thing as it may keep some other machines away. I wound up with a couple dozen coins but no jewelry although I felt I was close. HH!
__________________
Fisher 1280-x, 1220-x, Whites Surf PI Pro.

 

[therover]

Goldak,

Tough call on the double beeps, but when using my PI, most if not all of the double beeps I dig end up being longer pieces of wire, nails,, screws or long pieces of metal. I don't think I ever dug a double beep that was a chain or good target.

Also, most double hits for me have always been shallow targets and sound loud...the deeper targets or round objects are always single beeps that are less harsh or subtle rises in threshold. If there is a double hit that turns to a single hit as you move around the target and sweep at different angles, and the signal is wide, for me these targets are always wire or nails. Longer pieces of aluminum and brass screws sound kind of the same, but iron wire and nails sound more washed out and warbled. I am using a HH PI with the smaller coil, and after listening to the iron wire and nail targets and digging them to be sure, after about an hour I can tell when the target is different. Especially if the target is round or deep.

I have found that the only time I dig those double hits that sound washed out and wide, is when the targets are far and few between. I can honestly say that 99% of the time, the double hits are garbage. At least where I hunt. Then again, I may have left a chain in the ground, but I doubt any round object since they are distinctly different in sound on the HH PI. I think you have to get your ear tuned as the day goes on and as you use the PI more.

I have found that to hunt in trashy iron garbage with my PI, I only dig the deeper, softer beeps and the rises in threshold. Its the only way to pick through the shallow garbage. There are probably times when I have left some clad or possibly better targets in the ground when there are nails and wire all around, but since gold sinks faster then the nails, hopefully not much ! But the pain in the butt is, the smaller iron bits sound soft and I end up digging some of them too !

PI hunting is a totally different ball game, but I am starting to like it more and more. Just remember the main thing with a PI is to make sure the unit is running stable. It's much better to have a steady, smooth threshold when dealing with adverse conditions like black sand then running it hot and not being able to hear the slight threshold changes. The detector will beep on the shallow and bigger targets, but the deeper targets and smaller targets end up being slight threshold changes and may not give off the beep...more like a 'wow' or 'eeee'

La Jolla is a great beach...been there when I visited my cousin in San Diego.

JC

 

[Goldak]

Thanks JC, I'll learn more as I go. Part of me says "dig everything" but another part says "play the percentages". Your approach of ignoring the shallow signals in heavy trashy areas intrigues me and scares me at the same time but I may try it depending on the situation. HH! Goldak

 

[therover]

Until you are confident in what the machine is telling you. One thing I learned from the others on the forum is that listening to the audio of the target can tell you a lot. But you have to know your machine and have the confidence in it to move on when you feel the target is garbage. Problem with the PI ( at least the ones we are using) is that they do like iron, sound off good on lots of it and there is no way to tell via some form of crude discrimination that it's iron.

Leaving the shallow targets is a scary situation, but also one where you are playing the percentages. Just remember there aren't too many, if any, nice gold rings sitting 1-3 inches in the sand unless there is a clay or rock bottom at the 3 inch mark ( talking wet sand and in the water).

Not to pitch anything, but get Clive James Clynick's ( cjc on the forum) book Pulsepower. It's a great book and you will learn a lot about PI hunting, tuning and site conditions. For example, if you are finding nickles, sinkers, deep quarters...that's a good sign. It means your detector is going deep and the heavier targets are in range. If you are finding pulltabs at 10 inches...not good. That means the sand/ground conditions are loose and the light targets are sinking fast and deep, consequently the heavier targets
( gold) are down extremely deep and may be out of range. I have found that if I am finding nickles, it's aways a good sign and I usually end up with some form of jewelry ( be it silver, gold or junk).

JC

 

[JDknight34]

This is my first post. But I learn an awful lot reading what has already been posted. I was at a "la Jolla beach" about two weeks ago with a Sand Shark. The black sand does seem to false alot but (if you can stand it) it will still pick up targets. I dug 3 mercury dimes, 2 silver pre 64 dimes, 4 sliver pre-64 quarters, 14 wheaties, an 1893 liberty nickel, several other older nickels (40s-50s) an israeli (?) 1 Lirha, a bunch of recentent mixed change, a silver fork, a spoon, 3 interesting lead weights, a cheap ring, and the pieces of an old switchblade. All of this in about 3.5 hrs of detecting in an area probably 150 feet long and 30 feet from the cliffs.It is absolutely the best day I've ever done. Deepest target was probably around 6-8 inches and all the older stuff was on top or within the first inch of a clay layer extending from the cliff under the beach sand. The best thing was that I did not dig a single bottle cap or pull tab.

 

[Rockpile]

Double beeps can be a coin or ring standing on edge as well as two targetsclose together. I once pulled a 24K gold bangle that gave double beeps. I nearly passed it off as junk but it turned out to be Tailand gold weighing 1.3/4 ounces of 24K.

dig it all

 

[Goldak]

"This is my first post. But I learn an awful lot reading what has already been posted. I was at a "la Jolla beach" about two weeks ago with a Sand Shark. The black sand does seem to false alot but (if you can stand it) it will still pick up targets. I dug 3 mercury dimes, 2 silver pre 64 dimes, 4 sliver pre-64 quarters, 14 wheaties, an 1893 liberty nickel, several other older nickels (40s-50s) an israeli (?) 1 Lirha, a bunch of recentent mixed change, a silver fork, a spoon, 3 interesting lead weights, a cheap ring, and the pieces of an old switchblade. All of this in about 3.5 hrs of detecting in an area probably 150 feet long and 30 feet from the cliffs.It is absolutely the best day I've ever done. Deepest target was probably around 6-8 inches and all the older stuff was on top or within the first inch of a clay layer extending from the cliff under the beach sand. The best thing was that I did not dig a single bottle cap or pull tab.

"JDknight34, What a fantastic day you had! It sounds like I was 2 weeks too late and 2 miles too far north (closer to UCSD where we were dropping of my son). I'm encouraged to hear that older coins are still to be found in the wet sand. At least you left the gold rings for the rest of us!

 

[JDknight34]

Goldak, I was actually at torrey pines which has never before given up this many coins for me. I bought my dad the Compadre and wanted to show him how to use it so we went to TP beach. I did not expect to find much. I'll be back to pick up those rings tho... By the way, the sand shark PI has been great. I also own a Lobo ST and used the 18-in clean sweep on the dry sand beach (before I got the SS) and when I am prospecting. Although I have yet to find any gold nuggets with the ST, I get plenty of gold drywashing around Barstow. One of these days I am going to leave my drywasher at home and only bring my detectors to "force" myself to give it a good workout in a known goldfield.

At TP with the SS, I did have some trouble in areas with a bunch of Black sand. I changed batteries while I was there and it is kind of funny, but I experienced the chirping and instability mostly after I replaced the batteries. I wonder if having weaker batteries minimizes the sensitivity somehow. I would think that the voltage would be regular until they were almost gone. I usually replace my batteries after about 10-12 hrs (well before they go dead).

 

[Goldak]

JDknight34, I don't know that much about the sand shark but I have heard of other people's success with them as well. Interesting observations on the batteries. I've yet to change mine and I've hunted 3 times with this detector for a total of 12-15 hours. I'm about 2 hours from San Diego so I will only be down that way 3 or 4 times a year. HH!

 

[tvr]

With a Sand Shark, 90% plus of all double beeps have been wire, hair pins or nails. I did get one medium to thin silver chain with no pendant that double beeped one direction and went to single beep then back to double beep as I circled it. Almost didn't dig but it was early in the hunt and I was fresh.
tvr

 

[Goldak]

tvr, I really didn't want to hear that! I guess I'll dig up a few more of those double beeps now. HH!