Pinpointing question

["Dr.Tones"]

I'm wondering if there might be an issue with the pinpointer on my machine? When I activate it it seems to work half the time and the other half of the time it is kinda transient. I can hold down the trigger and it will pinpoint for a few seconds and then go silent while over a target, and then it will come back again. Sometimes it stays on and pinpoints and other times it just seems like I have to move the coil away from the target and pull the trigger again?

 

[MAK]

Mine does the same thing - almost as though it is nulling out. When I re-start the pinpont it seems to work OK. One thought I had is that I hunt with phone and that maybe the pinpoint highest tone is beyond the phones capability?

 

["Dr.Tones"]

Hmmm... I suppose that's possible. I actually have never tried my other phones with it.

 

[Ray-Mo.]

Some call it "ratchet" pinpointing .
Back in the day, to narrow the audio width of target response for defining a more accurate location of center, the technique called detuning was used. Detuning forced the electromagnetic field to become less sensitive to the target, thus reduced signal response width.

Many of today's metal detectors incorporate VCO (voltage controlled oscillator) into the all-metal pinpoint mode. VCO is driven by target voltage to produce varying audio pitch responses for target pinpointing and identification. Although VCO may be difficult and unpleasant to use on large shallow targets, it can be more of an advantage when multiple targets occupy the same pinpointing zone compared to monotone audio. With VCO, by narrowing the target area significantly, it is possible to hear the pitch peaks of two targets in close proximity more clearly.

If your metal detector has a continuous auto-retuning feature incorporated into the all-metal mode, you must be careful when hovering the search coil over a target. If you initiate Pinpoint while over the center of the target, the whole target may be masked as its response will be tuned out. This is why many detectorists experience "vanishing signals" in the all metal mode when attempting to pinpoint a target too quickly.

The above from detecting world.

 

[BrakingGnus]

+1 on what Ray-Mo said.

 

[MAK]

I understand starting to the side. There are some instances where the sound will drop off at its' peak and the re-appear if you will. Much different than nulling it out on the start.

 

[hershey1]

What you are describing happens sometimes with a coin on edge or a bent nail. Have you tried moving your coil 90 degrees? I hardly ever use pin-point myself. Most of the time I just wiggle my coil backwards until the target disappears and dig right in front of my coil. If you are using discrimination and other targets are under your coil when you engage pin-point mode then the other targets could also make a difference. You can check your pin-point accuracy by laying a few targets on a board and practicing over them while raising your coil. Ray was dead on with his information. Give that wiggle method a try as it may work for you also. HH

 

[Digger]

Could be that your not holding consistent pressure on the "trigger"? Another suggestion would be to try switching to Sizing Pinpoint where the width of the audio response does not change with each sweep.

 

[billwatson]

I just had my cxt out for the first time and sometimes noticed the same thing - pinpoint sound fading away. I had success by trying again, or ignore the sound and watch for the red ball to light up, or walk around 90 degrees and x the target. this is my first minelab - I was expecting it to be hard to learn, but it seems easier than I thought so far. hardest part so far is I have to dig alot deeper sometimes

 

["Dr.Tones"]

I hunt in VERY trashy places most of the time. I'm fairly certain now that it is the other targets in the ground surrounding my "good" target. I noticed that if I have one single target without any others in the vicinity that the pinpointer functions much smoother. My typical method of pinpointing is the minelab manual method verbatim. During some experiments today I noticed that engaging the pinpointer well above the ground tended to yield better results using a combination of the "wiggle back" method. Glad to hear its not a problem with my machine... Just me

 

[TheGeorgiaCanuck]

I use sizing pinpointing. If you trigger it just to the right of the target you get normal pinpointing; but I have found that if you trigger it just to the left of the target, you can get a *tighter* aka smaller pinpoint on the object. Too close and it goes silent.

 

[Big Boys Hobbies]

As others have said, your detuning it.