Okay, here we go:
1. The POWER SWITCH just turns the machine on and off. Turn it on.
2. The RANGE control gives you more depth the higher you set it. Start at 5.
3. The VOLUME control turns your volume up and down (duh).
4. The BATTERY CHECK lets you check the power of each battery. It's hard to tell, but it looks like you want a 38 to 45 reading on your meter when you check each battery.
5. The TUNER adjusts the frequency of the beat-frequency oscillator. The higher you set it, the faster and higher-tone signal you'll get.
Now, turn everything on and set the TUNER so you get a motorboat putt-putt sound. Drop a coin on the ground and swing the coil over it fairly slowly. The putt-putt should get faster and higher in pitch as it passes over the coin.
Experiment with the TUNER setting to find the position where it is easiest for you to hear the difference in the frequency when you pass over a coin.
Having said all that, I also must say that Jetco machines were horrible detectors. They have a depth of maybe two inches on a coin. if that. Other inexpensive modern detectors can go 4 inches in most situations, and deeper than that when conditions are right (no mineralization in the ground, and after a rain when the ground is wet).
The BFO technology used in this machine is obsolete. You're driving a horse and buggy down the interstate when you use this, and you'll miss most of the good targets. Best to hang it on the wall as a display, and get a modern machine.
Hope this helps!
