TR or Transmitter-Receiver: Term describing method of operation of early detectors. Some manufacturers still produce this type of detector. Electromagnetic field distortion caused by mineralized ground interferes with depth penetration as this type of detector does not ground compensate. It does balance conductive salt water effects so, it is primarily used in salt water and on low mineral salt water beaches or low mineral inland locations.
The TR mode is mostly used for ore identification. Don't expect great depth with a TR. It's a non-motion mode The mode you want to hunt with on the Garrett Scorpion is the motion auto discrimination or manual (ground balanced) mode. The TR mode uses the calibration points around the discrimination knob, which the operator must learn on its own. The TR mode gives a much more accurate reading for ferrous/non ferrous material. It works in conjunction with the discrimination knob, hence, in the TR mode, the further clockwise you turn it, the more conductivities are knocked out. Also, the mode is depth sensitive....if you are running samples of rocks over the coil, it is best to keep the coil stationary, say..... planted on a tree stump, and move the samples over the coil at the same distance over the coil. If you are using it on the ground, it is best to scrub the coil over the on the ground, so both the motion discriminate and TR mode are the same distance from the target being tested.
A favorite discriminating technique is what is termed as "reverse discrimination." This technique can be used with all analogue VLF/TR detectors. Search in the VLF all-metal mode and when a target is discovered, pinpoint it to the exact center and place the coil on the soil at that exact point. Without moving the coil, switch the mode to TR and lift the coil from the the soil. If the audio remains the same or decreases you have a good target.
Hope this helps. Most people don't utilize this mode. It's probably faster to just dig the questionable target, unless you are in an area prospecting with a lot of hot rocks.
