Question about Delta's Auto Ground Balancing... (and battery life)

[bb_maine]

I notice when I turn the machine on, it usually gives you a beep, and a VDI number pops up on the screen, usually accompanied by one depth bar... Most of the time, that VDI number is around 85. Sometimes 91, sometimes 41, and sometimes, there's no number, no beep - just that little lowercase letter 'd' (discriminate?). My question is first off, is this varying VDI number a function of auto ground balancing as I suspect it might be? Second, if it is, does it make a difference how high I start my coil off the ground when I turn the machine on? Waist level? A foot off the ground? Thinking that this might be the case, I have taken to turning the machine off and then back on again if I change terrain, say from farm field into pine woods, thinking it might help it to acclimate to the new ground type.... but maybe it's unneccesary... And lastly - one more question, unrelated, does your depth suffer as your battery dies down? Should you change it out before it completely runs out? I feel like my Delta is super snappy and gets great depth with a fresh battery, so i was wondering if the converse is true.... If anyone has answers to these, I will be a.) surprised and b.) very grateful!! Thanks, and HH! BB

 

[Dave J.]

Don't worry about the numbers that pop up briefly the moment you turn it on.

As long as the audio is reasonably loud when it detects a target, the batteries are still fine.

The "auto ground balancing" to which you refer is based on the principle of differentiation rather than "phase tracking", and is very fast (about a tenth of a second). It doesn't care where the searchcoil is when you turn it on and won't detune over targets. Of the two all metals modes (I think it's #2), one of 'em (it may be referred to as "autotune" in the manual) uses only a single stage of differentiation, which gives it additional depth in areas with low mineralization; but lacking phase adjustment it may be too noisy to use in bad ground especially rocky red clays. I believe this is explained in the manual although probably in a different way.

--Dave J.

 

[bb_maine]

Thanks Dave - I wonder though, why do the numbers change... If the number that comes up changes every time you tur it on, it must be in relation to something concrete... and like I say, they aren't random numbers... Usually 85, 81, 91, 41.... or just the 'd'...

 

[Monte]

I notice when I turn the machine on, it usually gives you a beep, and a VDI number pops up on the screen, usually accompanied by one depth bar... Most of the time, that VDI number is around 85. Sometimes 91, sometimes 41, and sometimes, there's no number, no beep - just that little lowercase letter 'd' (discriminate?).

That is not uncommon. I have experienced the same results with some variance of 'turn-on' display info. Yes, the 'd' is related to the Discrimination. I can get some different visual 'turn-on' infor almost anywhere, be it indoors or outdoors, by EMI or away.

My question is first off, is this varying VDI number a function of auto ground balancing as I suspect it might be?

No, it is not. The Delta is a factory preset Ground Balance design. Here is a cut-and-paste from the Owner's Manual:

Page #8 of Owner's Manual:
1. Ground Minerals
All soils contain minerals. Signals from ground minerals can interfere with
the signals from metal objects you want to find. All soils differ, and can
differ greatly, in the type and amount of ground minerals present. The Delta
has a preset gound eliimination setting. No user adjustment are required.

I have tried a number of different sample comparisons to evaluate the preset Ground Balance and it is just that.

Second, if it is, ... (It doesn't ... it's 'preset.') ... does it make a difference how high I start my coil off the ground when I turn the machine on? Waist level? A foot off the ground?

No need to play around with it because it is a preset "turn-on-and-go" model for quick and easy operation. Forget about the excess coil-height start-up stuff.

Thinking that this might be the case, I have taken to turning the machine off and then back on again if I change terrain, say from farm field into pine woods, thinking it might help it to acclimate to the new ground type.... but maybe it's unneccesary...

Unneccessary is absolutely correct. I use the Delta and find that it is very competitive in the price point it is in ... and simple to use.

And lastly - one more question, unrelated, does your depth suffer as your battery dies down?

Not really as it runs down, but once it gets too low, then you can see, and hear, a little loss in performance. I always try not to let a 'Greek' series models get too low and run t the point of a blinking indicator, or even run for very long once it hits the lowest setting. Full strength and mid-strength I find they work just fine. If I get to 1 then I just change the battery. That's me, and because i often am hunting for an hour of two or three and don't want the surprise of a too-weak or dead battery.

Should you change it out before it completely runs out?

I do, because just before 'running out' it is tired.

I feel like my Delta is super snappy and gets great depth with a fresh battery, so i was wondering if the converse is true.... If anyone has answers to these, I will be a.) surprised and b.) very grateful!!

The Delta is 'snappy', and since it has a saturated audio in the Discriminate mode you will hear good audio hits from all accepted[ targets as they will produce the loud audio response as if they were shallow. That's in the Discriminate mode.

I also hunt in the All Metal mode from time to time as there are a few places where I can benefit from a little added depth of detection, and I use A1 when hunting in places like deep wood-chip playgrounds. There, where some are maybe 12" or so on top of the ground, I am not dealing with ground mineral reaction as much and A1 will hunt deeper, and different, than A2. When I am working over ground surface, at least around here in NW Oregon where we have rather high iron mineralization, the A1selection gets too responsive to the ground so I opt for A2 which has a different GB setting and also different response characteristics.

Just remember, with the Delta and T2, the only Teknetics models that provide this option, you can adjust a different Sensitivity level for the Discriminate mode as well as for the All Metal mode.

As a reminder, here is the cut-and-paste from the Owner's Manual regarding this, and also some of the differences between A1 and A2.:


Page #11 of Owner's Manual:
Discrimination and All Metals modes have independent sensitivity settings.
First highlight the mode, then adjust the sensitivity level for that mode.

Page #14 of Owner's Manual:
A1 has more default sensitivity, about an inch more on a coin-sized object, but
will sound off over more highly mineralized ground.

A2 is more tolerant of ground conditions, but will be less sensitive over lessmineralized
ground. The two modes also have different audio characteristics.

A2 will provide better target separation, as the sound covers a

 

[bb_maine]

Thanks Monte - comprehensive and exactly what I was looking for. I read the manual several times when I first got it, and have since misplaced it, but this is all very good to know. Thanks for taking the time for a thoughtful reply, as usual...