Think your sensitivity is at 9? Think Again.

[BarberBill]

Cold and snow is keeping me out of the field so I got to comparing and air testing to day. I recently acquired a Conquistador umax and air testing inside, it didn't seem to compare to my Silver Sabre umax, nor my De Leon so I got to fussing a bit. Turns out, when comparing the three different machines, the sensitivity knobs don;t all point exactly the same. The knob on the Conquistador can be turned pretty well thru the whole max boost area to compare to #9 or #10 on the Silver Sabre umax. That far into the max boost on the SSumax gives significant chatter. The visual indication on the knob of the DeLeon varies as well. All machines when set just short of chattering, give nearly identical results in the air with the same coils although this particular DeLeon is about an inch and a half deeper consistently. My conclusion is when in the field, if one is looking for the most depth, it's probably best to turn the sensitivity to where it is unstable and then back off just enough for stability rather than depend on the markings. Likewise, I often throw a nickel on the ground and turn my discrimination until it crackles on the nickel, then back off just a hair to where the signal is solid, rather than rely on the labels on the knob. That way I know for certain I'm not discriminating nickels out. Hopefully these thoughts and observations will be useful to some.
HH
BB

 

[Shenandoah Digger]

I never even look at the sensitivity knob. I just crank it up all the way, and then slowly back it off until almost all chatter is gone. I leave a little, because I want to hunt on the ragged edge. Good signals will break through the chatter.

 

[BarberBill]

At least that way you know exactly where you're at, setting wise.
BB

 

[SkiWhiz]

I never even look at the sensitivity knob. I just crank it up all the way, and then slowly back it off until almost all chatter is gone. I leave a little, because I want to hunt on the ragged edge. Good signals will break through the chatter.[/quote I hunt the same way from time to time Shenandoah Digger I call this "running it ugly". Steve.

 

[tab-nabit]

Can't always rely on knob-label relationship.
Can either:
1. Reset knob on the pot shaft.
2. Mental note
3. Mark on the panel

I have reset one knob on one of my machines. When it was off, the knob indicated a sensitivity setting between 1 & 2, almost at the 2 instead of the "Off" position.
On others, if I set the disc on "5c", they may or may not knock out a nickle. But I don't like to set up to miss nickles.
Point taken that a knob indication is not always 100% accurate.

 

[sqwaby]

As Tab-nabit said it depends on where the pot shaft was at when the nut was tightened, check and see where its at when in the off position. You might have a pot that the stops where not quite in spec when it was manufactured.

 

[tab-nabit]

Can always turn a pot to minimum and see how far below the lowest label indicator it goes, then again to maximum and see how far above the highest label indicator it goes. Then can determine a somewhat indication of where the actual center of the pot range is.

As far as disc goes, the labels have actual targets that can be used i.e. 5c, 25c, tab etc. but Foil is a little more iffy as coins are consistent compared to Foil(s).
Almost like talking along the lines of "calibration" regards to knob/label indications.