F70 in HEAVY Iron ?

[Cal_Cobra]

I found a spot that was a heavily used railroad depot that adjoined a fairy landing that started during the 1850's. I scoped it out last weekend and found some great age indicators, but it's also loaded with trash, from 1850's rusting/rotting iron to the usual suspects of the modern era, it's loaded with iron. I hunted for a bit using the F70 with the small coil, with the sens set at 40, thresh at -9, tones at 3H, speed at DE, disc at 6, nothing notched. The old rusting iron produced a fair amount of high coin ID's (which unfortunately were all incorrect).

Seems like it has great potential. Is there any hope for a place like this using the F70 ? Any pointers using the F70 in an iron/trash infested site would be greatly appreciated.

Thanks,
Brian

 

[jimmyk]

Try one tone with disc at 5. Nasa Tom talks about that extensively as one of the best ways to help with iron masking.

jimmyk in Missouri

 

[Bill Ladd]

Either the small white one that the F75 uses, or the DD that's stock on the F75....
I also agree...use only 1 tone as it gets too confusing & 6 disc & try to rely on the audio more than the numbers. Read NASA toms info recently posted (even print or save it). He explains why he runs higher sensitivity than you mentioned. I employ this alot with the T2 on 21 disc....essentially the same as F75 on 6. The first time Tom had me try this on the T2, I pulled a 1770's spanish real' out of a bed of nails. I have not looked back since......
I was promiced a small T2 coil by "mid-Jan." but not sure where it is??
HH,
Bill

 

[jim tn]

I have the F 75, but "the same difference" and on those kind of sites I lean towards the small coil. The next best, or equal, is the 75's stock DD. I do, though, run sen. at 85, disc. 6 and either tone 1 or 3h. I personally use 3h a good bit and carefully scrutinize all high tones. Usually a good target among all that trash will repeat itself both with a good high tone and vid. There may be other numbers and tones as you sweep the coil over the target, but a good target will usually repeat both with tone and vid. Keep at it, you are on the right track. The F70/75 excels in a trash envirement and that gives us users of them a good jump on the competition as few other detectors do nearly as well in that envirement. That sounds like a great site. Good luck and HH jim tn

 

[Cal_Cobra]

Hey Everyone,

I was using the small 6.5" elliptical coil in heavy iron and was getting lots of iron falsing (I wish they truly were all 50cent pieces as ID'd, heck I'd still be there digging

I read Nasa Tom's report, but thought it written about the F75 ? Since reading his report I've had the disc set to 6, perhaps on the F70 it needs to go lower ? I'll try higher sens in combination with the lower disc next trip and see how it works.

With one tone selected effectively anything it hits will trigger a beep right ? I guess I don't understand how one tone will weed out iron

A 1770's spanish reale out of a bed of nails is most impressive, that's the kind of performance I need

Thanks,
Brian

Either the small white one that the F75 uses, or the DD that's stock on the F75....
I also agree...use only 1 tone as it gets too confusing & 6 disc & try to rely on the audio more than the numbers. Read NASA toms info recently posted (even print or save it). He explains why he runs higher sensitivity than you mentioned. I employ this alot with the T2 on 21 disc....essentially the same as F75 on 6. The first time Tom had me try this on the T2, I pulled a 1770's spanish real' out of a bed of nails. I have not looked back since......
I was promiced a small T2 coil by "mid-Jan." but not sure where it is??
HH,
Bill

 

[jimmyk]

At a discrimination setting of "6", and one tone, the nails will only give a blip or scratch. Larger iron will give a good signal, but can be figured out by the size of the signal. I've had to read NASA Tom's article several times to fullygrasp what he is saying. Give it a try. Investigate any signal that sounds good from severl directions. THEN check the meter. It's the best way to work through some iron masking. Wont get it all, but works better than most other detectors.

jimmyk in Missouri

 

[KurtB]

Give this a try. Disc at 0, 3 tone, thresh -3 to 0, site determines sensitivity. Audio will be busy with iron grunts but listen for the mid and high tones and check them at different angles. Zero disc. will help give away those false high tones. You will also reduce false high tones by using 3 tone instead of 3H. This allows you to use your ears more than your eyes. Wish the F70 had notch through out the full scale. On my Xterra 70 I can notch out the highest segment to virtually eliminate iron falses. The speed of the F70 and the small coil is a great combo and works great in areas like you mentioned.

Good luck,

Kurt