Some of the info I cut and pasted from the Kruzer User Manual, Page 19.
Threshold level is directly related to the Gain and iSAT settings. Please be sure to read the related sections of the manual carefully.
iSAT (Intelligent Self-Adjusting Threshold)
iSAT in General Search Mode (GEN)
.... iSAT adjusts the speed that the device recovers its threshold hum and eliminates the negative effects of mineralized soils. Increasing the iSAT in high mineralization will enable a more stable operation by avoiding false signals. This, however, may cause some loss in depth and it is normal.
NOTE: In high mineralization, if you receive too many false signals without disruption in the threshold hum, lower the gain first before increasing the iSAT. If the false signals continue, set the gain back to its original value and increase the iSAT. If the mineralization is low, you can decrease the iSAT and sweep the coil more slowly for a deeper detection.
iSAT consists of 10 levels. The device will start at level 6. It is recommended that iSAT should be increased in high-mineralization and decreased in low mineralization.
iSAT in Discrimination Modes
It is used to eliminate false signals caused by ground noise or hot rocks when searching in discrimination modes and the available range is between 00-10. Its factory default value is set to (1). You can change the value using the plus (+) and minus (-) buttons. If the device receives a lot of false signals due to highly mineralized soil or hot rocks in the discrimination modes, first re-ground balance. If the false signals continue, lower the GAIN and check again. In case the false signals still exist, try increasing the DISC. value. Regardless of all these, if the false signals still exist, first change the GAIN and DISC. values back to their previous levels. Then, increase the iSAT level until the false signals are eliminated. At the maximum level of iSAT, false signals will disappear or will be minimized. However, in some cases, increasing the iSAT will result in loss of depth for certain metals such as copper.
NOTE: When detecting in 19kHz, on wet or highly mineralized ground, in order not to miss smaller high conductive metals (silver, copper etc.) it is recommended not to increase the iSAT level too high.
NOTE: iSAT value ranges between 00-10. The factory default is 01. At ''0'', the iSAT feature will be inactive. If the ground is not highly mineralized or does not contain many hot rocks, setting the iSAT to ''0'' is recommended.
Monte