Garrett Groundhog - Best Search Technique?

[gsitexas]

I have read that the VLF/TR capability of the Garrett Groundhog makes it a good detector to use in iron laden sites to find the non-ferrous items.

My question is how do you use this machine in such an environment? Do you search in the VLF mode and then check every target in TR mode, it seems that this would be very difficult in an area thick with iron? I have read that some use a reverse discrimination technique.

For you Groundhog and other VLF/TR users, please help me understand how you use this or other non-motion VLF/TR machines to full advantage when hunting old home, school or church sites for coins and relics?

I recently acquired a "like new" groundhog and really want to understand how to best use this machine to full advantage.

Thanks in advance for your insight!

Keith

 

[Monte]

I know that quite often I read posts about them, or techniques, that are a little bit 'off-the-mark.'

I have read that the VLF/TR capability of the Garrett Groundhog makes it a good detector to use in iron laden sites to find the non-ferrous items.

Actually, the better TR's to use in iron infested sites would be some of the earlier straight TR's (non-discriminating) that operated at a higher frequency (about 100 kHz or so). Those would include the likes of the Compass Yukon and Nugget series, White's Coinmaster IV and others that were pre-discrimination, and early Garrett's that also came before their discriminators.

That said, I will say that in skilled hands a VLF/TR-Disc. model, such as a GroundHog, can do a little better in nail infestations than many of our modern motion-based discriminators. The TR's will have a "true progressive" discriminate function and deal with nails and bottle caps better than what we have today. The problems, however, include the fact that we have much more modern, higher-conductive trash today which is a challenge, and these oldies require handling technique that most hobbyists today just don't understand since they never had to learn it.

My question is how do you use this machine in such an environment? Do you search in the VLF mode and then check every target in TR mode, it seems that this would be very difficult in an area thick with iron? I have read that some use a reverse discrimination technique.

Yes, that is exactly what you have to do. The "Reverse Discrimination" technique is also something that is often quoted, but in error as many newcomers don't know what 'RD' really is.

The first thing to do is hunt with the smaller 7

 

[Sven]

Regarding the the VLF/TR units, I'm just got my vintage Dtex SK50 (Garrett Master Hunter clone) operational.
Sprayed down the two pots that were scratchy sounding, waited 30 minutes and reassembled the box.

I can now conclude the SK50 works as it should. Spent about an hour bench testing Canadian and US coins etc.At max. sensitivity, it will detect a half dime in VLF at 12" (slight sound difference) and 11" in disc. mode. In disc. mode I can disc. out those awful Canadian zinc pennies but lose the dimes and nickels as well. (Nickel plated steel) But still find the quarters, Loonies and Twoonies ($1 & $2 coins). This may work out to my advantage. Less holes to dig, can cover more ground cherry picking the higher domination coins as well as all US-copper, clad, silver coins and gold, silver rings. I have been finding an average 74 plus pennies per 3-5 hour hunt. I hate pennies.

I can't disc. out Canadian coins like this with my modern Detectorpro Wader when I go dirt digging the schoolyards.
It will be interesting to take one of these vintage units out again.

 

[gsitexas]

Monte,

Thank you so much for the feedback, I look forward to experimenting with the Groundhog at some of my old sites. If nothing else, it will make me appreciate my E-Trac and my various Treasure Barons. FYI, I did order a used book called The VLF-TR Metal Detector Handbook, however, not sure I will need it given your excellent advice.

Thanks again,

Keith

 

[gsitexas]

n/t

 

[slingshot]

There is one additional thing that I learned from the factory when I got mine a long time ago. The 71/4 groundhog coil was especially designed for the purpose of getting some idea of whether or not the target was ferrous in a/m mode. If the target was wider than usual, it was probably iron, where coin-sized objects would give a solid, standard beep. Some had success with this and it worked in parks for me, but I still had to use reverse discrimination to double check the coin-sounding objects.

 

[John(H)]

....Keith ....about 2 months have passed....how are you doing with the Groundhog??.......I find that some sites are so littered with iron and other debri that the old VLF/TR reacts to this type of ground as if it was mineralized.......I'm talking about a square foot area and having at least 10 or more iron targets besides all of the other junk......I would use the detector on the TR Discrimination side.........may have to use the ADS feature to smooth out the rough signals and to deal with all of the nulling effect....I would not ground scrub ...hold the searchcoil at least 2 inches off the ground.........listen especially for any of the weak signals...............Good Luck......Joe