CTX observations today

[squirrel1]

I went back to the relic field again today. Started out running CTX 28 man sens, long tone, deep off, fast off, ground coin separation, combined mode. Not a real good day overall. I did get this low tone but it was faint and blended in real well with iron tones and a small squeak of a high tone. You had to really concentrate to hear it. I kept sweeping and it was a cluttered signal with just enough of a low tone to hear. My screen cursor seemed to stay at about the 12 line but was jumping from the far left and almost over to the far right and I never saw any color whatsoever in the cursor. Screen said depth was 5 inches. Leaving all my settings as is, I switched to ferrous coin separation. Then I swept the supposed target. Now I could hear it real well, like night and day from before in ground coin. In ferrous coin the cursor still moved around as it did in ground coin and the cursor was without any color. I pinpointed the target and in pinpoint trace when sweeping I was getting color at around the 12-03/05 area and also color at the 12-40 area of the screen. I dug the target and it turned out to be a small button(a tad bigger in diameter than your standard today's shirt button with loop still attached. I put it in my pouch and continued to sweep for about 3 minutes still thinking about what I had just seen and heard. I always try to make each find a learning situation for me. I got curious and placed the button on clean ground and swept with above settings in ferrous coin separation. I actually got the same readings on the button on top of the ground as I did when it was buried. Plus the pinpoint looked the same too. Looks like the button is pewter with a copper loop on it. Seems to me the CTX was actually seeing both metals on the button. And that was in the detection screen as well as the pinpoint screen. That's wonderful in my book.
Another hour goes by and nothing, Started getting close to where I know for a fact a house use to stand. The iron gets thick so I backed the CTX off to 25 man sens, ferrous coin. fast still off, deep off. I get this signal that sounds more like a false than it does a good target. Screen reads 12-37 with just a pinhead of color in the cursor and said 6 inches. Turn 90 degrees nothing, no good tone or false. I kept sweeping and it just didn't sound good. I would have made a wager this was iron. I dug out a plug. Ran my pinpointer in the hole and come out with a small piece of a rusty nail. So I gave up and replaced the plug. I then changed my CTX to auto and it was running 27. I made a few sweeps and got back close to my dug plug area and ran the coil over it and bam, nice clear tone 12-37 and cursor full of color. Turned 90 degrees and nothing. I didn't understand why I was hearing the supposed target so well now, I went back to man 25 sensitivity and the target was giving the dirty signal again and cursor had the pinhead color in it again. I dug the target real slow turns out it was a 1925 wheat on edge at 5.5 inches. I actually missed the coin with my original dug plug by about 2 inches. I can't explain this one other than maybe the small nail defected the signal and caused me to dig in the wrong place to start with. Hard to believe the difference of this target between auto and Man 25 sensitivity. I can tell you I've dug several coins on edge in auto sensivity in areas I've pounded with etrac running at manual 25 and higher.

 

[sube]

Now you no why i still have not changed from ferrous the sound and vid are always better in my soil also open screen has the best vid #s and audio compared to the stock program with disc.How did the falsing issue go did you try it yet,As far as manual to auto the computer in the machine is always updating which should give you better vids and audio another words it's better than you.lol

 

[Larry (IL)]

In manual sensitivity, you are assigning one value to all of the operating frequencies but Auto is handling each frequency individually for the best setting possible in each frequency. I found that Auto out performs manual unless I am hunting in All Metal and then I can really crank it up in manual. Randy has gone into detail about this, it might be on the classroom forum, could be on here somewhere too.

 

[squirrel1]

Yep tried alternating the bin freqs and the false follows whichever tone is locked in the approx 40-50 conductive. I did learn one thing by doing it. If I was going to water hunt to find gold only I would have say the 12-01/12-35 bin set on the highest freq. And I agree with you the auto sensitivity on the CTX is real good. I think one can overdrive and underdrive the detector on certain targets when using manual sensitivity causing one to miss some of them.

 

[sube]

To bad about the false issue I'm getting real good at telling what a false is most are nails or wire when you pinpoint them they always move from your pinpoint coins don't unless on edge if it repeats east to west west to east and pinpoints where i think it is I'm digging lot of reasons for not seeing it from north to south other junk in hole or close and if your hunting a hammered out spot these are the ones you should be paying attention to .sube

 

[earthmansurfer]

Thanks for that informative post squirrel1. I haven't experienced on the CTX yet what you described, but I did experience stg similar on the E-Trac. Here is what I think:

If you have a smaller piece of iron above a coin - small enough or positioned well enough that it won't completely mask the coin - running hot sensitivity will light the iron up and mask the coin further (I think it breaks up the detection field as the first metal that it hits does so. Also consider, the detection field is not smooth, it goes in and out - Mike Hillis I think showed this). If you run auto - the iron is not as "excited" and allows the coin to be heard.

When I experienced this on the E-Trac, it was in the opposite order, there was a coin at around 2" with a large piece of iron at 4". I was running so hot (30) that the 6" - 8" deep iron was overpowering the smaller coin. Was a terrible signal on the coin. I actually thought I might have had a very deep masked coin. Once I dug it up and found no iron next to the coin and just the larger iron below it, I knew my hot settings were the culprit. (The coin was actually in the first plug but I never checked it and kept digging to find the iron.)

So, when hunting in general, one has to be careful of running too hot as perhaps you'll excite the iron (or mineralized ground) to a degree as to overwhelm the coin signal. But, if you are going for depth and willing to sacrifice shallower losses, then near max sensitivity does go slightly deeper than auto (in my somewhat iron mineralized ground).

Albert

 

[Big Boys Hobbies]

Good observations. I will be testing this myself.

 

[Jason in TN]

I have found that running in auto the CTX runs better my self have said this on beach hunting post several times. Don't know why some folks think you have to crank it up full in manual to get any depth it just ain't so. Now if you are looking for deep stuff and don't care to dig signals that are bad crank it wide open and dig every thing that makes a noise. You can do that with any detector though. You purchased a high tech detector turn it on auto and let it do it's thing.

Jason

 

[earthmansurfer]

I have found that running in auto the CTX runs better my self have said this on beach hunting post several times. Don't know why some folks think you have to crank it up full in manual to get any depth it just ain't so. Now if you are looking for deep stuff and don't care to dig signals that are bad crank it wide open and dig every thing that makes a noise. You can do that with any detector though. You purchased a high tech detector turn it on auto and let it do it's thing.

Jason

Jason, I don't think I am saying you need to crank it up to get "any depth". Actually, I don't think I've seen people saying that here (though Bryce did say "Sensitivity manual 26 (depth not good until I did so)"). But from actual in ground testing with the CTX (and E-Trac) in my somewhat iron mineralized ground there is a DEFINITE difference in depth, between say manual 30 and auto 23 (or so) - ok, only about 1" or so though. On some deeper 8" - 9" targets the auto setting wouldn't hit on them when it was below the 25 or 26 level. Running auto at 19 to 23ish seems to hit all targets at 7" in my ground. But, IF you are after deeper targets, fringe targets, then a near max setting works to add some depth. Of course this is not true in all soils. If your mineralization is too high then you get the brights on in the fog analogy. But, I tested for this and in my ground it is no problem. On a side note, I OFTEN hunt for fringe depth targets, just pushing the machine to see what it can do. It is a puzzle of sorts - I mean, I am mostly digging deep zincs, but it is awfully fun!

On a down side you do, of course, get more falsing with a hot manual sensitivity. And, it is just worsened by running 50CO (compared to Combine) in my many comparisons. Running in auto, the CTX is awfully smooth. And as others have said, auto +2 seems to be a bit more stable than +3 in many grounds.

Albert

 

[Guvner]

It will flat out point out at where the center would be if it was flat so to speak. So if it's almost up and down you might be 3 or 4 inches from the target. I did get used to realizing whenever I miss a coin on the plug and it was a good hit I have a coin on edge in the wall somewhere... I have sure went over places I didn't think had even clad in them to only find a lot of on edge stuff the CTX refuses to miss.

G..

 

[stasys]

I dont know if high sensitivity can mask good targets near iron, because coil transmitter works on the same power all the time, low and high sensitivity on the control panel dont have any relation with it. Sensitivity its just what you want to hear.
I found this after playing with oscillator, but why in detectors manual producers dont say it I dont know but maybe I missed it?

 

[earthmansurfer]

You might be right Statsys. I was just saying what jumped out at me and perhaps it was something else being the cause. I often hunt very hot, even with mid depth targets and haven't noticed much masking. I really learned to detect with a T2 and running hot with that detector was an art form imo. I sort of carry over what I learned there to the E-Trac and CTX - which are QUIET in comparison. Considering all that is in the ground where I and many of us hunt, it sure is complicated to say exactly why things sometimes happen the way they do.

 

[Digger]

Good observations! Thanks for sharing them. One of my favorite "combinations" for coinshooting is Ferrous - Coin Separation, Combined Audio, Auto +2 or +3 for Sensitivity, an acceptible amount of discrimination in Pattern 1 and a fairly open screen in Pattern 2. (FE line 35 rejected to minimize wrap around) When the area is trashy, I hunt in Pattern 1 and use Pattern 2 for target "verification". When the trash isn't very thick, I hunt in Pattern 2 and use Pattern 1 for target "verification". By verification, I am referring to going back over the target area to see if both Patterns provide a consistent target location, consistent audio response and consistent TID. Not so much the numbers in the TID, but the image location on the SmartScreen. If I am still not totally sure as to what the target might be, I go to Pinpoint to see if the target "stays" in the exact same location as it was in the hunt mode. If the primary target doesn't "move" when using both Patterns and Pinpoint, and it makes it's SmartScreen appearance in an area I know to represent a coin, I pull out my digging tool and retrieve it.

When the CTX 3030 forum first started, I encouraged folks to use the Auto Sensitivity for a couple reasons. One, Auto (even with an offest) would provide very good results for most locations. Two, I didn't want people to think they had to crank it clear up to get respectible depth. It is engineered, afterall, different than the previous FBS detectors. With any detector, Sensitivity set too high can create a situation where the "noise" overshadows the target signal. My preference is still Auto +2 or +3 at most of the sites I hunt. However, if there isn't much trash in the area, I might glance at the Auto setting and change it to Manual with a couple "bumps" positive. In other words, if Auto is running at 23 and the site isn't trashy, I am fairly confident I can run with a manual setting of 25 without causing too much feedback or falsing. And if it does false or chatter with the manual settting, I usually find that slowing down the sweep speed will stop those chatters and still allow me to run with the higher manual Sensitivity. If I get into an area that an abundance of trash causes Manual to get the jitters, I simply put it back into Auto, and make a few sweeps to determine if I need to adjust my offset.

To better understand how I came to these conclusions, here are a couple posts I've made regarding Sensitivity and the CTX 3030.


How much is too much?

Posted by: Digger Date: August 03, 2012
Sensitivity is the detector's level of response to targets and their environment. Increasing the sensitivity may provide a more solid response on targets, but it will also increase the "false" signals from that "environment" and on smaller ferrous targets. Your detector is also more succeptible to electrical interference with a high Sensitivity setting. Decreasing the Senstivity will likely cause your detector to operate "smoother" and provide better discrimination / TID. But having it too low it can also reduce your depth of detection. So in regard to your question as to "how much is too much"...... as much as your "detecting skills" can handle. If you feel you need to have more depth of detection, you'll likely turn it up. If you get tired of repreatedly rescanning the "beeps" to see if it was the solid hit of a target or another false signal, you'll likely back it down some. I know the manual says to not use Auto on the beach. But on the beaches I hunted during test procedures, I found Auto+2 was very stable and effective. I just made an effort to sweep a bit more slowly to allow the detector to better analyze (and adjust to changes in) the sand. JMHO HH Randy



Here is how Sensitivity and the display works......

Posted by: Digger Date: July 05, 2012
The CTX 3030 has three internal signal channels (high, medium and low) used to identify targets. The CTX 3030 continually measures the magnetic ground interferences that affect these channels and adjusts the level of Sensitivity individually for each channel, to provide the most stable TID for each channel.

When using Auto Sensitivity, the left bar and numeric value indicates the highest Sensitivity Level that either the high, medium or low channel is operating on. The right bar indicates the "Suggested" Sensitivity Level, as determined by the CTX 3030. This "Suggested" level is the average Sensitivity Level of the high, medium and low channels. Each channel is set to a different level of Sensitivity individually by the CTX 3030 to provide the most stable TID's. As an example....... if the CTX 3030 determines the Sensitivity Level for each channel is to be High = 20, Medium = 17 and Low = 11, the left hand bar and numeric indicator will read 20, representing the highest Sensitivity level of the three channels. The right bar and numeric indicator will display the average of the three channels, which is 16. 20 + 17 + 11 + 48, divided by 3 = 16. When you implement the Auto Sensitivity offset with an offset of +3, it will not suddenly change the value of both bars by 3. Instead, it increases each channel's value by 3. So in the example given earlier, the channels will become High = 23, Medium =20 and Low = 14. 23 + 20 + 14 = 57, divided by 3 = 19. So the left bar and numeric indicator will display 23, representing the highest Sensitivity level of the three channels. And the right bar and numeric indicator will display 19, the average of the three channels. When using an "offset" the numeric value of that offset will also be displayed in a little icon, to the left of the left Sensitivity bar.

In Manual Sensitivity, the left bar and numeric indicator represent the level you have set. The right bar indicates the "Suggested" level, just as it does in the Auto Sensitivity mode.

The primary difference between using Auto Sensitivity and Manual Sensitivity is that in Manual, ALL three channels are set to the same value. In Auto, the CTX 3030 determines the value most stable channel. Auto Sensitivity with the offset allows you to "offset" each channel by a value from -3 to +3. The offset allows the user to be more conservative, or aggressive than the one chosen by the CTX 3030, while allowing it to "compensate" for ground interference changes during your hunt.

HH Randy