Fisher CZ Forum

Does anyone find any improvement (lessening) of iron falsing when the sensitivity is turned down, from, say... 4.5 to 4.0 or 3.5? The 3D is tough to run in a bed of nails due to the propensity to high-tone 'chirp'. They're easy to discern, but each false takes a little time to analyze.

Thanks in advance!

Go Rebels, seems like the 3d's are not good in iron, so I use a different detector for nail infested spots. Not to say you can't find old coins among the nails, but the 3d dosen't seperate well. Darn deep though.

After you GB the machine turn the GB knob a hair (real hair) clockwise and many of the falses turn to iron grunts. I never turn down the sens. Once you go below 4.5 ish it looses depth. Disc always on zero. This is for hunting old coins.

If this winter turns into a "Winter" we're use to, I'm sending the 3d to Tom D for a tune up. That may reduce some of the falsing in iron. I have noticed much of the falsing is from iron just outside the coil and as you said it slows you down to analize. When that happens, if I can PP the target, then go over it from different angles. If it high tones 360 degrees I dig it. If it grunts in a couple small sweeps, it is usually iron. I have dug hundreds of targets to realize this.

After the tune up, I may have to change strategies.

Quote
Steve O
If this winter turns into a "Winter" we're use to, I'm sending the 3d to Tom D for a tune up.

Steve O... why wait so long? Tom tuned my CZ3D and had it back to me about ten days. (That included two way shipping and being tune during the Christmas/New Year holidays.

-NEBeachcomber

NE, Ten days? He must be busy. I'm waiting for the weather to turn cold and nasty, I'm still using it and taking advantage of this 40 to 50 degree (daytime) weather. You're probably right though, spring is not far away.

NE, did you have the falsing problem and did the tune-up help correct it? What other changes did you notice after tune-up?

CZ3D although deep does have masking and falsing problems in nail invested areas plain and simple...Be advised 4.8 is about tops to run sens. at but goes as deep or deeper than anything on the market...yep Tom is the guy to send to for a tuneup but again run over about 4.8 sens. and expect problems...

Steve O... I didn't really notice any iron falsing before I sent my CZ3D to Tom D. I'm not saying it wasn't present... as I bought this detector used and didn't get it out before sending it to Tom D. to be tuned. My biggest issue with my series 1121 CZ3d was that it did not accurately identify nickels (V, Buffalo, Liberty, or Washington).

When my detector came back from Tom D the nickel window issue had been corrected, my coin signals seemed much clearer and more defined. I was told by Tom that while my detector was achieving good depth with the factory tuning, he was able to slightly increase the detection depth of my detector to approximately 12 inches. (This depth adjustment was made in Florida's neutral soil.)

The most interesting change that I noticed after having my 3D tuned was that two gold rings that I tested (before and after being tuned) came in with a high tone rather than the normal middle range tone? (At this time I think this will be a good thing for me.)

Lastly, being a "whimpy" New England resident... I'm waiting for the weather to warm up a bit more before I take it out for a real spin to some old sites.

I bought a used 1021 3D and used it for about a month before sending it to Tom D. I can tell you it had the same falsing in iron before and after. What changed for the better was target ID, both audio and on the meter ID. The audio report on mid tone targets was clearer as well. He said he was able to get a bit more depth, but I cannot atest to that since I had not dug anything deeper than 8-9 inches prior to sending it to him. When I reduce the sens(4.9 to 4 -3.5) to reduce falsing in iron, it seems to help a bit on very small iron, tiny broken pieces, or brads,etc. If you swing over a larger nail(8d or bigger) or 1/4" or larger washers, it still falses and I loose quite a bit of depth. I don't reduce it very often if I'm finding good deep targets. I'm not willing to miss a good target so I don't have to dig a few pieces of iron.

Does this adjusting the GB technique a little positive work on the F75 platform too?