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15 hours ago, Glenn in CO said:

My TDI was modified as well as my friend’s TDI Pro was modified by Reg Sniff.

Good stuff, Glenn.  Thanks!  I seem to recall (now that you've posted this) that you've previously reported using a TDI for coin hunting.

I assume yours is the original Pulse Scan TDI (big box) similar to the one Steve wrote his coin detecting article for.  And then you had it modified (presumably to make it better 😁).  What mods were done and how did that improve your unit?

I can see you (and others, including Steve) have emphasized that you use the TDI in difficult ground.  My sites here in Southern Indiana are intermediate in mineralization so not as bad as what you've encountered in Colorado.  I know Jeff McClendon has said that in greater Denver alone there is a huge range of mineralization depending upon location.

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GBA, I couldn't help it... spent most of the day thinking about it, and decided to spend the waning hour and a half of daylight at my old school ground with the ATX.  Only I can fully appreciate the p

GB :  I know there are some coin/relic guys who will try to use those balls-to-the-walls pulse machines , for coins/relics.  Since, sure, you can "get a coin to 1.5 ft. deep", blah blah.  I saw a few

I'm not sure if this is the same reaction other PI's get, but on my GPX, coins hit louder and narrower than big nails do. Nails, for me, sound longer, and coins hit faster if that makes sense.  Coins

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1 hour ago, GB_Amateur said:

Good stuff, Glenn.  Thanks!  I seem to recall (now that you've posted this) that you've previously reported using a TDI for coin hunting.

I assume yours is the original Pulse Scan TDI (big box) similar to the one Steve wrote his coin detecting article for.  And then you had it modified (presumably to make it better 😁).  What mods were done and how did that improve your unit?

I can see you (and others, including Steve) have emphasized that you use the TDI in difficult ground.  My sites here in Southern Indiana are intermediate in mineralization so not as bad as what you've encountered in Colorado.  I know Jeff McClendon has said that in greater Denver alone there is a huge range of mineralization depending upon location.

Hi GB,

The modification to my TDI was reducing the delay below 10us. Reg was hoping this modification would help in detecting smaller gold. Particularly the wire gold, unfortunately the modification did not help on this type of gold. 

My question would be in mineralization such as yours, would a TDI or PI achieve more depth than a VLF because of less mineralization?

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1 hour ago, Glenn in CO said:

My question would be in mineralization such as yours, would a TDI or PI achieve more depth than a VLF because of less mineralization?

I don't know, yet, but in the case of the TDI/SPP we're going to find out!

 

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  • Steve Herschbach changed the title to Pi ( TDI ) Coin Detecting Advice Request
3 hours ago, Steve Herschbach said:

It's always fun watching VLF people talk about pulse machines and what they can't do. Gives me warm fuzzies, it does. :smile:

Steve, one of these days let's meet in an appointed Sacramento park .  That's only a few hours drive from both you and me.  And let's do some turf hunting :  You with a pulse, and me with a standard machine.   Would LOVE to see the results.  Ok ?  🧐

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32 minutes ago, Tom_in_CA said:

Steve, one of these days let's meet in an appointed Sacramento park .  That's only a few hours drive from both you and me.  And let's do some turf hunting :  You with a pulse, and me with a standard machine.   Would LOVE to see the results.  Ok ?  🧐

Tom your not going to seed the park with bb's and pellets first are ya? LOL

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2 hours ago, Tom_in_CA said:

Steve, one of these days let's meet in an appointed Sacramento park .  That's only a few hours drive from both you and me.  And let's do some turf hunting :  You with a pulse, and me with a standard machine.   Would LOVE to see the results.  Ok ?  🧐

Got nothing to prove to anyone else, but thanks for the offer Tom. I'm not into arguing or proving things to anyone but myself. It's way more about applicability than capability. In general, just stick to the VLF and be happy. :smile:

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12 hours ago, Tiftaaft said:

So, GBA, I owe that Buff to you and this thread.

If it was one of the 1913-S's I might accept it.  I already have a 1936 but thanks anyway.  :biggrin:

Strong date so likely dropped early in its lifetime.  If I followed your progression it was a bit over 10" depth.  Is that the deepest coin you've found at this site?  Now I bet you're wondering what other old coins are down there just out-of-reach of your VLF's....

Good showing for the ATX in 1 1/2 hours.  What is the size of the coil you were using?

Neat looking owl (do you know the variety?).  I wonder why it was on the ground unless it had some prey trapped.

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36 minutes ago, GB_Amateur said:

If it was one of the 1913-S's I might accept it.  I already have a 1936 but thanks anyway.  :biggrin:

Strong date so likely dropped early in its lifetime.  If I followed your progression it was a bit over 10" depth.  Is that the deepest coin you've found at this site?  Now I bet you're wondering what other old coins are down there just out-of-reach of your VLF's....

Good showing for the ATX in 1 1/2 hours.  What is the size of the coil you were using?

Neat looking owl (do you know the variety?).  I wonder why it was on the ground unless it had some prey trapped.

Yes, definitely one of the best conditioned Buffalo's I've dug.  I was using the 10x12" DD coil.  I also have the deep seeker, but haven't unleashed that monster on the turf yet (... yet).   The only reason my trash pile was as small as it was, is because of all the hours I have previously spent with my VLF's... but most likely either ignoring the low iron tones (by design/setup) or some too small at the depth for the particular machine I was using.  It was between 10" and 11"... and yes, that may be the deepest coin I have recovered there.  A few of the other oldies were in that 8 - 9" range, but this was a solid 10"+.  The site has been pretty dry from a keeper standpoint over the past week or two... so I was surprised to find a coin last night.

I'm not sure of the owl variety...Could be a Barred Owl, but the way he was sitting on the ground, I couldn't see his underside.  I assumed he had his evening meal on the ground, which is why I didn't try to get any closer. 

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