What's the rule of thumb with coil size and accurate depth gauge assessment?

[king-ghidorah]

I remember briefly seeing someone mention something but I don't remember what the rule was?

Like what happens if I get a 15x12 coil and how will 6" register on the depth gauge as opposed to the default 10" coil?

same scenario with a 6" coil?

 

[Bowie]

From the factory the machines are calibrated for the particular coil that comes equiped on that machine. Using a smaller coil will cause the depth reading to read deeper than the target actual is in the ground and just the opposite for a larger than "factory equipped" coil. This has nothing to do with the actual depth of detection of a particular size coil or wind, only the depth reading as Im sure you already know or have read because of all the variations and mineralzation involved.
LOL, I dont know much but I did know this and someone else may pop in and add to it but it runs true to all make of detectors from what Ive read and learned.
Im a Whites guy but you guys have me chomping at the bits for a minelab,lol.
Anyways I hope I shed a little light on the subject for you.
Raining here today so I will be bored,
HH,
John

 

[Mike Bearden]

The stock coil is by far the most accurate on the gauge, but, every situation will be target & site condition dependant past about 6" in depth so I always trust how the target sounds .... from weak to strong to best judge it's depth.

Always works with me no matter what brand of detector is in my hand at the time

Some detectors depth gauges are pretty accurate for the most part even when using smaller coils but I've made a habit of trusting what I hear over what the gauge shows.


Good Hunting
Mike

 

[Hungry]

I don't know about the depth gauge reading, But some time ago I rang Coiltek inquiring about an 18' coil. I was told that they did not intend building one as the 15" WOT was as big as you could go without loosing depth and sensitivity to small items. Also , the bigger you go ,the more Electro magnetic interference you get, making the Detector unstable. Hope this helps in some small way. Bob

 

[treasurefiend]

I don't know about the bigger coils but I find that my SE Pro is usuially off about 2 inches (assuming that the depth reader is 12") LIke if the depth meter is half way down I assume it is 6" when more times than not it is really only 4 inches deep. Its kinda frusterating when I think I have a deep coin like 8 inches but it only turns out to be maybe 6...

 

[dewcon4414]

I agree, i can normally tell if i have a deep coin by the sound when i pinpoint. I say that because normally im running pretty hot sensitivity and a high gain so everything sounds the same except when i pinpoint. Gold star for John about the standard coil calibration since the detector does take size into consideration. John i still have a whites DFX, but i took the leap and havent regreated in the least. Each have their place. I wasnt shabby with the DFX, but the Explorer for me tends to take out a lot of that... "did i miss something today" i was feeling. I did find the use of the DFX really made the learning curve easier. I think a lot of it had to do with the information in Jeff Fosters books which i found i could apply to about any detector.