Jump to content

Understanding The Threshold On The Eq800


RobNC

Recommended Posts

Ok, so this is a subject I have not touched on much and despite me finding things I do wonder.

Concerning Threshold of the Minelab Equinox in park mode and field mode specifically. Mine is set fairly low at volume lvl 4. There are times when it goes silent yet I have no "target" on the screen. What exactly does it mean when you are going over an area and the threshold tone disappears or "nulls out to silence" for a second but yet there is no target audio?

Does it mean my ground balance is not set correctly? Seriously wondering, as I want to get every last particle of performance out of my Equinox 800. Thanks in advance for answers!

For what it is worth, the majority of my hunting is done in Park 1 with some modified tone break points from default. I may venture into Field 1 every now and then, otherwise it is the modified park 1.

Link to comment
Share on other sites


2 hours ago, RobNC said:

What exactly does it mean when you are going over an area and the threshold tone disappears or "nulls out to silence" for a second but yet there is no target audio?

It means your coil swung over an object (ferrous or non-ferrous) that you have rejected on your machine’s discrimination pattern......a threshold that goes silent momentarily is called audio blanking.  For instance, if you reject the ID’s between 14-18, and your coil passes over a square tab or any metal object that’s within the rejected range I just described above, your threshold will blank (become silent) momentarily. 
 

Back when I detected with a Minelab Explorer, I used an audio threshold,  because I had a small amount of discrimination set (for small iron objects).  I could tell when I passed over iron when my threshold went silent....Now, I hunt with my Equinox and use no threshold.  That’s because I have no ID’s rejected on my Nox.  I hunt in all metal, and utilize the machine’s Target Tone, Tone Pitch, and Tone Break settings to adjust typical iron and small foil target ID’s to have lower volumes/pitches than the the non-ferrous objects I want to hunt for. That gives me the delineation I need without the use of a threshold.   I now prefer hunting with no threshold...it’s one less parameter your brain has to account for. 🤓

  • Like 7
Link to comment
Share on other sites

12 hours ago, Raphis said:

It means your coil swung over an object (ferrous or non-ferrous) that you have rejected on your machine’s discrimination pattern......a threshold that goes silent momentarily is called audio blanking.  For instance, if you reject the ID’s between 14-18, and your coil passes over a square tab or any metal object that’s within the rejected range I just described above, your threshold will blank (become silent) momentarily.

But what if you aren't rejecting (notching out) any TID channels?  This happens to me sometimes.

One possibility is poor audio transmission.  The WM08 (which I always use) is picky about not being shielded by one's body.  For example, if I turn around to walk away from the detector when the WM08 is in my shirt pocket, the sound disappears.  When I return, facing the detector, I pick up the signal about 30 meters away.  I've read about some people having problems when the location of the WM08 is opposite the detector (e.g. swing with right arm but WM08 in left pocket).

Another possible issue in the audio path is the physical connection(s) between the WM08 and headphones -- specifically the plug(s)/socket(s).  It's doubly bad if you have to use an adapter to go from the WM08 3.5 mm socket to get to the headpones' 1/4 inch plug.

Now, if you're not using the WM08, then the blame goes somewhere else.

Link to comment
Share on other sites

The issue of Threshold blanking in AM or with no disc/notch was discussed in detail in this thread (Chuck, you chipped in with some input there too).  Also includes a good summary and explanation of the different threshold type used in gold mode vs. the other modes.  Great refresher on Equinox Threshold.  Enjoy...

 

 

  • Like 1
Link to comment
Share on other sites

1 hour ago, Chase Goldman said:

The issue of Threshold blanking in AM or with no disc/notch was discussed in detail in this thread (Chuck, you chipped in with some input there too).

I had forgotten about that thread, so thanks for the reminder.  However, for my situation, the only relevant thing I could find was something Jeff McClendon posted there:

With the horseshoe button engaged in any mode in the urban and suburban areas I detect in, there are breaks in the threshold even with my coil pointing at the sky, the horizon or of course near the ground, but motionless. I can only assume it is very low frequency EMI or something similar which is not registering as a numerical target ID due to signal strength or some other factor but it does disrupt the reference threshold tone in Park Field and Beach and also disrupts the slightly more traditional threshold tone in the Gold modes even more.

In my case I keep the threshold set rather low (4 or 6) in the Park and Field modes.  When using Sunray Pro Gold headphones (cool or cold weather) I can hear the threshold just fine.  During the summer with earbuds, because of the ambient noise the threshold often isn't too noticeable.  (And in that case I don't turn it up because added to the ambient noise it is just too much for my brain and ears to handle.)  Thus I need to get back to cool weather detecting (just so happens that's beginning now) to collect more data.  I did notice threshold dropout the other day (actually with earbuds) but barely and I just ignored it.

Jeff's theory of low frequency EMI is still in the running in my case, although the area I've been hunting doesn't typically have much of the usual kind of annoying EMI.  I don't think it's variable bad ground (as mentioned in the Minelab Treasure Talk post) since my ground isn't that bad to begin with.  The exception, though, could be coke, in the form of discarded charcoal from cooking fires or even refuse from burned buildings.

Bottom line in my case -- more investigation needed.

  • Like 1
Link to comment
Share on other sites

The only things I have disc'd out are -9 to zero. I run my threshold at 3. Heard it some yesterday blanking or rather going silent. So at this point will assume it is some heavy iron garbage I surely do not want.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...