Spectra V3i bottle cap reject

[Joe Kool]

Yesterday I went detecting, with my V3i, in an old park that is still in use. I found a 1907 indian head penny, a 1910 V nickel, a 1943 war nickel and about $2 in clad. A section of the park was loaded with bottle caps and I had to turn the Bottle Cap Reject to 12 to block them. I found a few clad coins among the bottle caps and the Bottle Cap Reject seemed to work well. This is the first time that I have used the Bottle Cap Reject. Up untill yesterday I didn't have to use the Bottle Cap Reject because the past places I have detected there were not enough caps to worry about. Not having much experience using the Bottle Cap Reject, I was wondering if using it causes any ill effects such as such as depth loss or detecting gold rings.

 

Amazon Forum Fav 👍

Family Maps of Hinds County, Mississippi, Deluxe Edition - Grab it through Amazon!

[deepskyal]

Are you using the stock coil with it?
With your finds from the park so far, it might be worth your time to invest in a small coil to get between the bottle caps....or just dig the caps and get them out of the way.
Iron "masks" good signals.

I bought the 5" dd coil for mine to use in a trashy park and discovered I can go right under powerlines with it. It's like new territory where other detectors couldn't go.

If you're just pulling out clad in a trashy area of a park that's kicking up IH's, V nickles, etc., you very well may be losing some depth on coins and jewelry. Just think how many others may have detcted that park and passed over the trashy areas....

Al

Al

 

[Joe Kool]

deepskyal, I'm using the stock coil. I'm planning to get a smaller coil by next spring but at the moment I don't have one. There are so many caps in this area that I hit a cap on almost every swing. To dig them all out would leave the park looking like a plowed field and probably take weeks. I'm mostly looking for gold and silver rings in this area, and the bottle caps give VDI number that gold rings would give. The caps often read on the 22.5kHz frequency and I concerned that rejecting the caps will also cause a gold ring to be rejected. I guess I'll have to take the wife's jewelry box out to the yard again. A few weeks ago I hunted a hard hit park that has a carpet of pull tabs in the area around the picnic tables. I found a few coins but I didn't spend too much time there. I went back a few days ago. I set the Recovery Delay at 30 and Ground Filter to 5 Band Pass and was then able to move very slow and check out each signal. I found over $2 in clad and a war nickel. I have never seen anyone else detecting the areas around the picnic tables, probably because of all the pull tabs. I detected around only 10 tables, there are a lot more tables. I may try this technique in the park with the bottle caps.

 

[earthmansurfer]

When BCR gets above 6 you will probably start to lose some good coins, especially at depth.

But, here is what you should DEFINITELY try. The default mode of the spectragraph is "intensity" (the other choice is "consitency") at a "base threshold" setting of 90. If you change that value to 65 or so, you are going to see the spectragraph start to smear more on the bottlecaps. The high performance program (I think) uses it. Bob at whites did it for this very reason (bottlecaps)! But coins generally won't smear like that, unless next to iron, which I guess is the iron smearing really. I think the setting is under live menu, search. You have to look for it but it's not hard to find. It's toward the bottom of the expert menu.

Understand, that BCR is just an iron form of rejection - it causes iron signals to break up, I use it at a level of 2 and don't have a bottle cap problem.

BTW - Wow, I like to run a fast recovery. But I have never run the stock coil with a RD at 30! I do that with the 6X10. The lowest I have ever run the stock is at 60. If you aren't getting double hits, then you should be fine.

 

[chukers]

I couldn't stand that bottle caps read as quarters with the stock coil... when I switched to the 950 coil that fixed that... its a better coil IMO than the stock DD one

Chukers

 

[Coin Digger]

If you switch your analyze view from sizing to polar plot, the bottle caps will show up as loops in the upper left quadrant. Coins will show up as straight lines in the upper right quadrant.

 

[Joe Kool]

earthmansurfer, I have just started the experiment with the fast RD setting. As I posted, I set the Ground Filter on 5 band pass and the RD on 30. My sweep speed was very slow, 4-5 seconds, timed with a stop watch. The duration of the beep is about the same as when using a RD of 80, the 10 band pass and a 2 second sweep speed. I didn't cover much ground but it let me search in the pull tabs where other people didn't get the coins. As I said I just started to play with this. I'll try some different settings but what I've done so far seems to work ok. I watched a video on utube and the guy was barely moving the coil. He was finding things. I tried it but the hits were poor. Moving the coil just a bit faster the hits were much better but with the RD set at 80 the duration of the beep was so long the the coil had moved to the next beep with little seperation. The duration seemed right with the RD at 30. I tried the RD at 25 and it seemed a little short.
Maybe something I should have pointed out about the bottle caps I was trying block. They were new caps that were not rusted, that were from the surface to about 2 inches deep. They seemed to read much stronger then old rusted caps. I started the BCR at 4 and went up to 11 untill most started to break up, but too many were not. At 12 almost all were blocked. I found a few clad but after about a half hour I moved to a area with less caps. I'll give it a try another day. I'll try some of the suggestions I received here. Thanks

 

[Joe Kool]

I went back to the park and searched in the bottle cap area again. I was able to block the caps with a BCR setting of 3. I don't understand why nine days ago I needed a BCR setting of 12 to block the caps and friday I could block the caps with a setting of 3. All the other settings were the same. But I didn't find any coins in the bottle caps after a 45 minute search. My partner also didn't find any coins. We think some one had detected the area since my first trip.

 

[Coin Digger]

Like Forrest Gump said "It Happens"