I can't remember the forum that this old post came from, however I had it saved and it might help you.
One important thing to remember is to ground balance with the disc set only at "0" like listed on number (3) below.
Original Post:
Now here are some of my instructions in using it in beach hunting and many of these tips can also be used in the field of prospecting.
(1) First, turn the unit into the LOCK position. Then listen for any interference and use the frequency adjustments to eliminate any interference. Remember to move the frequency adjustment a small amount and then wait for a small period of time for it to lock in. Remember, there are 32 frequency positions that can be obtained with this control. Once you get use to the unit, you will generally get to know where the quietest spots are and it will come second nature and quick to do this.
(2) Do not try and adjust the frequency control with the unit in Fast or Slow Track. What I have found, is that sometimes the auto track tries to lock onto the interference, making it hard to eliminate it.
(3) Set the threshold so as you can only just hear it and set the discrimination to "0" .
Now comes the important steps and if this isn't done correctly, false signals and sounds can occur.
(4) Turn the unit to Fast Track. Move the coil up and down to the sand a few times and place the coil directly onto the sand for about 10 seconds. Then again move the coil up and down to the sand a few more times. You will see that that the ground balance has come in very quickly and should be fairly steady.
(5) Then switch it to Slow Track and then repeat the same procedure as was done in Fast track. This is the fine tuning adjustments.
Please note, when you place the coil directly onto the ground, the unit tends to keep ground balancing the ground effects out, and you will find that it quietens down pretty quick. This is especially more noticeable in the high mineralised ground in the goldfields.
(6) Once this has been done, switch the unit to lock.
(7) As the unit was designed for prospecting, it doesn't have the prefixed discrimination set to compensate for salt water effects, as other beach PI units have. If you still get any affects from the salt water, you may have to increase the discrimination up to about "2" to eliminate these false signals. I haven't had any problems with noisy operation going from the dry sand, to the wet sand and into the water with the unit ground balance set correctly. Generally I use it with "0" discrimination set.
( As the unit was designed for prospecting, it has a lot more sensitivity than a normal beach PI unit. To drop the sensitivity, use the threshold and reduce it, even to "0" and this will also help reduce any false signals you may be getting. By doing this, you will not miss any targets normally associated with beach/water detecting, eg:- coins, rings and chains.
(9) If you come to an area in the water that is causing a lot of problems, then ground balance over this problem area and then switch it to lock. This should sort out any problems.
I had a customer who was having problems with certain areas in the salt water, that was causing all sorts of signals. The area was near a place that was well known for copper ore, and was a very productive copper mining area during its time. These problem areas had many rocks which would have contained traces of copper ore. I told him to ground balance over these rocky outcrops until the unit was quiet and then turn it to the Lock position. He did this and found that he could move from the dry sand and into these areas without any problems. He also found a nice gold ring on that day he tried this set up.
(10) Make sure the cable is looped slightly near the coil and then taped to the lower stem. Then bring the cable straight up the stem for about 18" (450mm) and tape. Also tape the cable in several places between this section. Do not use cable ties as these can eventually damage the cable. I prefer to use insulation tape as no damage will be done to cable and it holds the cable more secure with less movement.
Hopefully this will help out.
