SD2100 - Tuning

How do I know re mineralised areas, and this is after tuning my SD2100 (original model). As a newbie it is very difficult to tell if it's me or the machine . Dont want to spend extended time re balancing & threshold adjuctment is via a a small screwdriver. (am around Taradale)
John

hi
  mate i know nothing about the 2100,but the threshold you should only have to set once.hold the coil heaps off the ground and set the threshold so you can hear a very faint hum.turn it down until you can`t hear it and and then turn the threshold up till you can just bearly  hear a very faint purr.    when you have the threshold set raise and lower the coil to the ground.if the machine makes more noise on the way down OR the way up,your machine is not ground balanced.you have to set your machine so that the sound dosen`t change on the way up or down.  every time the machine goes out of balance due to changed ground conditions you have to re balance the machine.
  in short you should make your machine as quiet as possible,when hunting for gold
  hope this helps

daywun wrote:in short you should make your machine as quiet as possible,when hunting for gold
hope this helps
dave

I could turn mine off and it would be perfect then


You actually gave me a better understanding of GB, in that one sentence :

when you have the threshold set raise and lower the coil to the ground.if the machine makes more noise on the way down OR the way up,your machine is not ground balanced.

Bring on the yellow

Cheers


Corey....

Never owned one and wont.
They were good at the time of there release, but so was a GT Falcon.

I expect a few harsh feedback comments from these remark but I must give an example: I was using a 3500, and I pin pointed a target that I found in a run that produced a bit or two. I invited a mate with a 2200 to find and dig. I said: If you find it its yours. I had already cleared the area in an effort to make the signal clear. After a confusing few moments ( Swing this way, hang on swing this way) I said get your coil off and try the one I used to find it. Still no signal.
I put my gear back together and said something like "stand aside" Bang the gold was as clear as your mum "saying tea is ready"
The 2200 simply didn't hear the signal that the newer machines are tuned to pick up.
If memory serves me, it was less than a gram ( maybe .3 but only about an inch or so down. ( the invisible nugget to the 2200)
Sorry: I may have side stepped the original question about mineralisation but the problem with the earlier machines was mineralisation.
Brett.

There are four different ways of tuning a SD2100, one is the threshold tune pot which is usually a set and forget type activity, Method of tuning; adjust threshold knob till there is a nice smooth and stable hum in the headphones or speaker so that you can use the threshold hum as a reference point to identify faint buried target responses from, the smoother and more stable you can make this the better you chances of finding deep gold (a smooth threshold also helps in concentration).

The second is the manual interference frequency tune control which on earlier SD2100's required a screw driver or the later ones (blue control box) had a dedicated interference control knob, Method of tuning; place the stem of the detector directly out in front of you with the stem parallel to the ground and the coil at right angles to the shaft, then do a full 360 deg turn (physical rotation with the coil shaft held out in front of you) from South to South again paying attention to the threshold by listening to the stability of the threshold as you go (overall smoothness), after the 360 deg rotation go back to the position where the most interference (warbling or constant repetitive hammering sounds) was noticed and then manually tune the detector either with a screw driver or via the control knob to a point where the instability is less or gone, you have now found a frequency were the detector can operate without things like power lines or the earths magnetic field interfering with good signals in the ground.

Now that you have achieved the above it is time to check on the ground balance in your chosen area which means you now have to tune the detector to suit the ground conditions by adjusting both channels of the machine to null "out" the ground (this means tell the detectors electronics the ground measurement you have chosen should be the zero reference point by which everything else will be measured (zero means the detector will ignore all the ground that makes a similar reading allowing targets to be heard). This is where the Minelab PI machines are very good, they can achieve a very effective ground balance (Null) whilst still maintaining amazing depth in areas of high mineralisation (this is what you are paying the big bucks for, to date no-one else on the planet can do this effectively). Method of tuning; start by pumping the coil up and down in relation to the ground with the coil held as parallel to the ground as possible, pay attention to the threshold, is the coil making a noise as the coil is moved away from the ground or towards the ground?

Now flick the ground balance knob to the channel one position, the SD 2100's have two channels or if you like are essentially two detectors in one by selecting channel one you are now deciding to manually ground balance channel one on its own by turning off the second ground balance (this allows you to concentrate on the channel as you perform the ground balance without the second channel interfering with the audio). The first channel of the 2100 is a lot less sensitive than the second so is less intensive to tune or ground balance especially with a DD coil, by turning the balance knob one way or the other you will notice if the sound generated when the coil is pumped becomes worse or better. Once the direction of the tune control is decided upon, usually it only takes few seconds to achieve a null in channel one, now just flick the GB (ground balance) knob to the second channel and perform the same procedure, but keep in mind the second channel is more sensitive than the first so will require a finer adjustment (channel one is for larger deeper gold nuggets and channel two is for small shallow/deeper targets).

Once the second channel has been balanced you can then re-unite them by selecting the both position (middle switch position of the ground balance switch) where the two channels are combined again so you will have both sensitivity to small and large targets but where the ground is nulled (ignored). Get into the habit of checking the GB regularly by pumping the coil, usually it will be channel two that needs fine adjustment unless the ground is extreme or you have moved to a different area. Do not use the VLF method of leaving the GB slightly positive (method used to identify hot rocks) as any loss of Null to the ground will cost gold, the better you can become at keeping your detector balanced the better the results will be.

Hope this helps,

JP

PS the SD 2100 benefits from a booster speaker combo especially on the small deep gold mentioned in the above post by Echidnadigger.

Hey brett I bet it wasn`t scotty with his 2200, I won`t say any more don`t want to start a blue
cj

Hi Guys,
I just have to comment on this topic as I own a 2100 and until this year I had no luck but since the beginning of the year I have picked up a few bits of gold thanks to a few guys I met from the forum.
My 2100 has a hear all booster and use a 250mm eliptical monno which has found all the gold from 0.1g to 3.8g.
I turn my threshold back to where I just cant hear it after doing my GB with success, main reason is to eliminate the noise from the mineralised ground so I dont come home with a headache(on some ground) but like I said it still picks it up no probs and when you get a signal you know about it.

Bret you say you wouldnt own one but Im the opposite to you as I happened to go out a few weeks back with a bloke from on here with his 4500 coupled with a 8" round monno and did a test on a test piece of lead about 1/3 of a bullet, results were I picked it up at 6'' above ground and he picked it up at 5 1/2" then went about our detecting when another bloke rocked up with his 4500 and after talking to him about the test we did he gave his a go over it using either a 10" or 12" monno(not sure) and picked it up at 5 1/2". As you would expect I was happy with those results, so to me the only benifit with the newer machine is the smoothness and less mineralised ground noise you have with it where I have to turn my threshold back to silent and loose a few mm,s maybe when using a monno coil.
$1500 compared to $6k my budget allows for the 2100.
just my 2 cents worth
Ossie.

I had one of my best ever years with the SD2100 (in excess of 230 ounces for the season) with my biggest ever find at 3 1/2 feet which turned into a quartz kidney reef with over 150 ounces enclosed (will never know the true amounts because of another party involved but you could probably double the amounts and still be off the mark). The point is the SD 2100 was and still is a very good gold finder so long as the user is up to speed on its use, in the right hands it can still easily keep up with the big guns (except for high mineralisation and overall stability, that is the sole realm of the GPX series) especially in new country.

JP

Hope you are not needing a Platypus coil up your way JP with all that rain

CJ wrote:Hey brett I bet it wasn`t scotty with his 2200, I won`t say any more don`t want to start a blue
cj

OK, there is some good ones out there.
Brett.

Hi All
CJ , Okay what is so special about (Scotty's SD2200d or v2 ) please explain cause Im looking at buying one.
Scotty, maybee you could shed some light on what I should be looking for and asking, what sort of set up do you run, Im getting the impression that they are still very good machines with alot to offer.
cheers
Lee

To all responders - many thanks (JP puts it in understandable words - as usual - ) and be the post [+] positive or [-] negative they all assist a newbie!!, Given each of us has varied experiences and something to offer.

jt wrote:To all responders - many thanks (JP puts it in understandable words - as usual - ) and be the post [+] positive or [-] negative they all assist a newbie!!, Given each of us has varied experiences and something to offer.

Sorry JT,
looking at your original post and then my post, I may have come across as negative. That wasnt my intention. My fault, apologies.
Brett.

Brett - many thanks for your post - I took it as a different point of view and it helps in the overall scheme of things
john

Thanks JT,
I'm looking forward to reading about your hunt for gold and seeing pictures of your finds.
Good luck.
Brett.