Details on SD 2200v2 controls (from Instruction Manual):

        Rear Panel Controls (end battery connects to)

Power - The Power switch controls the power supply from the battery to the control box. Always switch the detector “Off” before connecting or disconnecting the coil or battery, and when not in use.

Channel (Ch1, Ch2, Both) - The Channel switch selects the channel used for searching: Ch1, Ch2 or Both. Searching is usually done in the Both position which gives the maximum sensitivity to the greatest range of targets. When detecting in highly noisy ground, the selection of Ch1 rather than Both might improve the stability of the threshold. However, sensitivity to certain types of targets is reduced when using only Ch1 and is not recommended for normal searching.

Threshold - The Threshold knob is used to adjust the loudness of background sound. Minelab recommends a soft audible headphone signal which is comfortable to listen to for extended periods.

Audio (Shallow, N, Deep) - The Audio switch can be used to enhance the signals produced by different types of targets. In the Shallow position, signals from small targets close to the surface of the ground will be amplified, allowing easier detection of such targets. This option is best suited for quiet ground. For normal detecting conditions use the N position which responds to all signals without boosting. The Deep position is recommended when looking for big targets at greater depth in noisy ground. In this mode random soil signals are smoothed, making small changes in the audio signal from large deep targets easier to hear. It may, however, mask some signals from very small targets near the surface.

Tune - The Tune button is used to lower the effects of electromagnetic interference from sources such as power lines, radio transmitters and other metal detectors. The Tune control is engaged by pressing the push button switch. If electromagnetic interference is experienced when using the detector, simply press the Tune button once to automatically select the best detection frequency.

Tone - The Tone knob can be adjusted to suit an individuals hearing by changing the pitch of the background threshold tone.

       Front Panel Controls (end coil connects to)

Balance Mode (Fixed or Tracking) - To get the best from your SD2200v2, it is important to know how different ground conditions affect the detecting process. Ground contains not only sand, but also many different chemicals, minerals and salts. These extra components are referred to as ground mineralization. This ground mineralization will often produce a sound from the detector, known as “ground noise”. The SD2200v2 has the ability to cancel out the effects of ground mineralization so that it minimizes ground noise, while retaining maximum sensitivity to metal targets. Cancelling out the effects of ground mineralization is referred to as “ground balancing”. This ensures that welcome signals from objects such as gold are not confused with unwelcome ground noise. The SD2200v2 has automatic ground balance which adjusts to minimize the effects of ground mineralization when set in Tracking mode.

Iron Discrimination (Disc, All Metal, Disc + ID) - This switch allows you to select between simple discrimination (Disc mode) and discrimination with tone identification (Disc + ID mode), or to turn off the discrimination altogether (All Metal mode). In the case of All Metal mode, the detector will give varying volume and pitch signals but this information does not indicate the type of metal in the object found. In Disc mode, a strong signal from a ferrous (iron) object will cause the threshold to be ‘blanked’ or silenced. In Disc + ID mode, a strong signal from a ferrous object will cause the threshold to be ‘blanked’, just as it does in Disc mode. In addition, a signal of medium strength will trigger the ID mode. In this mode, non-ferrous objects usually produce a tone with a steady pitch while a ferrous object will usually produce a tone with a varying pitch. Repeated sweeps across the target might be required to confirm whether the tone is steady or varying. Note, however, in this mode some non-ferrous objects can also produce a tone with varying pitch, making the operator more likely to mistake a non-ferrous object for a ferrous object. This mode of discrimination should not be trusted until the operator has sufficient experience with listening to the tones produced and comparing them with the objects detected. If the signals are too weak for accurate discrimination in either of the discriminating modes, the detector will return to the All Metal mode signal. While in the Disc + ID mode, a signal which is too strong to be discriminated will produce a rapidly pulsing signal with constant pitch. This is called an overload signal. A target producing this sound should not be interpreted as being a ferrous target but be investigated.

Level Adjust - The discrimination Level Adjust knob gives the operator the ability to select the sensitivity and likelihood of a target being ferrous or non-ferrous. The same control also affects how the detector recognizes mineral effects in the ground as opposed to metal targets, when ground tracking.

Recommended Settings for Beginners - Channel to Both, Threshold barely audible, Audio to N (Normal), Tone to whatever suits the ear, Iron Discrimination to All Metal. Run Balance Mode in Tracking over representative ground that contains no trash for a couple minutes, then switch to Fixed. The Level Adjust has no effect with Tracking off and Discrimination off. If you activate Iron Discrimination, turning Level Adjust to the left will lessen the discrimination effect. You will dig more trash, but have less chance of gold being misidentified as iron. Turning Level Adjust to the right (clockwise) will eliminate more trash, with greater risk of gold being misidentified as iron. If Balance Mode is set to Tracking, turning Level Adjust to the left makes the ground tracking more aggressive for highly variable mineralization, but at more risk of tuning out gold. Turning Level Adjust to the right (clockwise) will make the ground balancing less aggressive, with less risk of gold being tracked out, but more ground noise may be introduced.

Since the two functions of the Level Adjust tend to work against each other, it is recommended you use either Tracking or Iron Discrimination, but not both at the same time. That way the control will only have one function depending on what you have activated, and adjusting it will make more sense. If you must run both Iron Discrimination and Ground Tracking at the same time, set Level Adjust at 12 o'clock.

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