F 70 and nickles

[Steve from Ohio]

Was out today with the F70at a local yuppie park full of trash. A lot of tabs and clads. Plus lots of garbage strewn about. I must of picked up 40 plastic containers and lots of other trash. Some clads were pretty deep. I found $24.87 worth of modern coins today. Too bad none were silver or gold. They will come! One other MDer was out and he was not having any luck. Just tabs, buried aluminum cans and bottle caps. I think he's going to get an F-70 after he saw what I was doing. He was running an older metal detector and was not doing very well.

A few things I noticed.

When hitting nickles, they will have a very steady reading of 31 no matter how you attack the target. I like to move around the area swinging over the target at several angles. I have noticed that certain removable pop can tabs will read all over around 31 but will not be on 31 steadily. I also noticed that the tabs will make the audio fuzz a lot when using the edge of the coil whereas it does not fuzz with nickles as badly.

Also on dimes as compared to solid copper pennies. Dimes will read 72 or a little higher almost always. Solid copper pennies will read from 65 to 71 depending on how deep they are. They will bounce around just like tabs. The zinc readings today were always right on target. I dig everything that indicates a coin weather zinc or not. The F70 was spot on with every zinc penny.

I also noticed that the F70 on quarters is a killer. I hit a quarter and the depth read 6 inches. I raised the coil over the target another 7 inches above ground with zero discrimination and 70 sensitivity. Still rang out loud and clear. I have had real good luck running 0 discrimination and sensitivity as high as I can run without falsing. Even when falsing, the F70 still gives out a very bell like sound with a coin. So I have found that if I can force myself to ignore all the noise, I can still find the deep ones with tone ID instead of on autotune.

So far I have found that if the numbers don't jump around, (except for copper pennies) you can bet that it is a coin. If the numbers jump and the edges give a real bad fuzzy audio report, then you can bet it is a piece of aluminum from a can.

I like to move around a target to get a good idea of where the coin is. The pinpoint is really accurate. If the coin is under the biggest void in the center of the coil nearest the mounting point, you will get more accurate readings for depth and position. That is not mentioned in the manual.

I have noticed that the back end of the coil past the mounting area is dead. It seems as if the back 1 inch or so of the coil (nearest to me) is not reading the coin at all.

I was wondering if anyone has had any experience with the F70 on an ocean beach. I'm going to Florida for the winter and would love some feedback as to how the F70 works on the beach and at the waterline.

Overall a great day with my F-70.

 

[Mr.Bill]

If one sweeps the coil at least the width of one's shoulders while trying to ID a target, the ID will lock on easier, ( It's in the owners manual ).

Don't do little short wiggle, wiggles over the target trying to get the ID numbers to set in, this will cause it to jump the ID reading all over the place.

 

[markg]

I know the manual states to sweep fully over the target, but what if there's more than one target close together.

 

[John 'n' W.Va]

n/t

 

[John 'n' W.Va]

n/t

 

[Mr.Bill]

it should handle it. There again, that's why they offer the small coil.

With usage comes knowledge, and if that fails, revert to the owners manual.

All kidding aside, a little wide sweep would help considerably.

Have a nice day

 

[Streak!]

the audio seems to be better at a moderate sweep speed...but the ID is MUCH better with a crisp swing....regardless of the width. Since the audio and visual is processed separately...this kinda makes sense. When I get a target that doesnt Id too well (a little bouncy)....but SOUNDS great........it will usually ID kinda high too.....and almost always will ID higher than it will when I get it on top of the ground.
I found this a bit annoying at first....till I discovered the benifits of it. Averaging UP (which seems to cause the higher IDs IN the ground at normal sweep speeds).....allows me to recover targets I might dismiss otherwise as junk. When I get a target like this.........I just use a real crisp swing speed over the EXACT center of the target......and it will ID a LOT better.....and a lot closer to its actual "on top of the ground" ID. The AUDIO will suffer a bit with a real fast swing....but the Visual ID is a LOT better....closer to its real ID.......and stays within a few VDI numbers. Other guys experiences may vary....but thats what I have found in MY ground........in MY hunting areas. I also will circle my target to find the optimum angle for Id and audio response.... Streak!

 

[Mr.Bill]

Certainly proper sweep speed is essential to having a good ID reading. I should have mentioned that also, bad, bad me.

The manual does make a strong point not to do the coil wiggle, wiggle over the target if you want a good, solid target ID. I believe John Gardner knew what he was doing when he made mention of that function. As with all detectors, audio should be your primary method of ID'ing, the the meter. One way to handle it would be to get a good ID with a sweep speed then switch to a different speed for TID. Aw, too much work, dig it all.

 

[Jackpine Savage]

n/t

 

[Waterdog]

You must have a bad coil. I just tested my F70 and the back of the coil reads just fine. I get a hit from the tip of the front of the coil all the way to the end of it.
HH

 

[Steve from Ohio]

I may have. I know that when I pinpoint, the front of the coil is OK but the very back near the mounting point is totally dead. No matter what I do, the coil just does not register anything on the back end. I will do more tests before I call Fisher just to make sure.