XL Pro Sig Bal question

[tvr]

What does the Sig Bal control really do?

Took the XL Pro with the 600 coil to a school area that I know is real trashy; music room and auditorium end. I have dug buckets of trash from this end of the school and virtually no jewelry. (for what ever reason the jewelry seems to be at the end of the school by the gym and the music room end doesn't have much). The gentleman who has been directing school plays for years laughed when he first saw me detecting this end a couple of years ago; says when they wire lights, build sets and sweep up scraps, all the little bits go out the doors into this area. Lots of screws, nuts, nails, wire, foil and can slaw in the area.

I figured it would be a good learning exercise with the new to me XL Pro.

Like with other detectors I've used in this area I had to walk to a clear area to ground balance and then over near the entrances to hunt.

When I got to the hunt area, the XL Pro was making a lot of noise. The Sig Bal was at about 3 o'clock, I turned the Sig Bal to about 2 o'clock, walked back to where I could ground balance and then back and things were much better.

So, is Sig Bal a sensitivity / gain adjust on the front end of the receive circuit? ... adjust it so the ground (or trash) matrix doesn't overload things?

Pulled $1.63 in clad out in about 1.5 hours of hunting. Dug a lot less trash than I have using other detectors but did dig some foil and pull tabs to make sure they are what I am thinking they are. Starting to learn where the mid conductors generally line up on the meter and starting to hear the the beep sound variations on this detector. Swinging it real slow over tabs that are reasonably flat to the ground surface the tone wavers a little and the needle does too. Kind of neat! Will have to test some rings we have to see how they sound.
tvr

 

[a4wdguy]

The Sig Bal could be called a receiver gain adjustment. It does control the strength of the signal allowed into the circuit. In very mineralized ground, reducing the Sig Bal will reduce the amplitude of the receive signal, allowing you to pick up targets deeper... It's kind of like headlights in the fog. High beam headlights will definitely allow you to see further than low beams. However, if you are driving in fog, so much of the light from the higher powered high beams will be reflected back to your receivers (eyes) that your processor (brain) will be overloaded and you can't see. However, the low beams, in the same situation, have less light reflected, so will actually allow you to see further.

 

[tvr]

Thanks for the input! Adjusting it does make the detector act pretty similar to the sensitivity adjustment on other detectors I have. The naming of the control and not seeing mention of sensitivity adjust in the manual was a little perplexing. Since the balance routine for this detector is more like a self calibration than an adjustment I wasn't sure how it all tied in.
tvr

 

[david bull]

thats the first time I've heard it explained that way a4wdguy, but that's pretty much how it works.When I'm in trashy areas or sand I set my signal balance as low as 11oclock and run my disc at salt. This seems to open up smaller targets since the meter still id's iron targets.I dig anything that moves the needle up even to just below zero as platinum and small white gold can be found in this range.DBULL

 

[tvr]

I've read a couple of posts about good finds when digging the small needle jump off iron. So far, when I dig the needle bump where it shows mostly iron but does a little bump above iron it has all been iron larger than an inch long nail so I started ignoring the little bump targets. I haven't taken the XL Pro to the beach yet.

The XL Pro is running stable, but is there a chance I may want to run a little lower on the Sig Bal setting than just low enough to make it stable?

I don't have a lot of time yet on the new to me XL Pro, it's been fun learning and definitely looks like a keeper.
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[Hombre]

Hello Y'all

I'm no expert on the XL Pro, only have had mine a couple of years. I only give it enough signal ballance so that it ground balances good, that maybe at the preset mark or above or below the preset mark. It all depends on the ground you are balancing to. Once you have established a good GB at the highest signal balance setting, it is running as hot as it will go.Then I lock the GB in..........my 2 zincs worth

 

[a4wdguy]

<snip>

The XL Pro is running stable, but is there a chance I may want to run a little lower on the Sig Bal setting than just low enough to make it stable?
<snip>
tvr

First, if you are only looking for shallow targets, there is no reason to run the detector hot. For instance, there is a field near me that has a bed of hot rocks 9" below the surface. I have found a CW 3 ring bullet and a high school going steady ring at 7 to 8 inches. By turning the Sig Bal down, I am able to find those targets that other people miss by running full power. Sometimes, less is more.

 

[crazyman]

Before the SL's the the gain or signal balance (receive sens.) was hard wired or preset with the transmit sensitivity being adjustable. With the SL's they preset/hard wired the transmit sensitivity and gave us the ability to adjust the receive sensitivity or gain which is actually a true sensitivity adjustment. People tend to over use the signal balance thinking they will get more depth but that is not how the signal balance works since it is on the receive end of the signal. I can tell you how I've set mine up for years going back to the 5900/6000 Di Pro SL's. I first ground balance with the signal balance on preset then with the coil resting on the ground I listen to the threshold and look at the needle on the meter. If the threshold is steady and the needle is not twitchy or jumpy I slowly increase the signal balance to the point where the the needle and threshold start reacting to the ground or other outside interference I then start backing it down just to point where the needle stops twitching and the threshold is steady once again. I then reground balance and start hunting.

 

[tvr]

Thanks for the inputs!
I am going to try crazyman's set up routine. Sounds like a quicker way to get to the initial hunt set up than doing four or more Sig Bal adjusts and ground balancing after each like the manual indicates.
tvr