practice and testing detector capabilities

d1010223 said:

Hi

Trying to help my daughter get into detecting and she has an old Garrett a2b. Wondering if there are any ways to test your ability and the capabilities of your detector with something that responds similar to gold? Would some lead-tin or silver solder (couple of grams?) behave similar to a small piece of alluvial gold?

Any tips greatly appreciated

Cheers

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grubstake said:

In general, lead sounds/responds very similarly to gold with a Garrett A2B. I think silver solder would likely be more conductive than a gold nugget, so might sound a bit different.

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grubstake said:

Are you using the small coil (7½") or the 10"? From memory (40+ years ago), the smaller coil would find about a 5 gram bullet at 6" and the bigger coil at 8" in typical Victorian goldfields ground. If your soil isn't very mineralised, you should get more depth.

That's a pretty old detector though and the electrolytic capacitors might be dead or dying by now, so don't be surprised if doesn't perform well (if it works at all). Garrett A2B's (Groundhog and Deepseeker) were the weapon of choice back in the day, but wear and tear plus age, takes its toll on the circuitry.

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d1010223 said:

Hi

Trying to help my daughter get into detecting and she has an old Garrett a2b. Wondering if there are any ways to test your ability and the capabilities of your detector with something that responds similar to gold? Would some lead-tin or silver solder (couple of grams?) behave similar to a small piece of alluvial gold?

Any tips greatly appreciated

Cheers

Click to expand...

d1010223 said:

Yes its the smaller original coil. Yeah it probably should be in retirement. Do far its reliably getting a 5c at about 4” deep in sandy soil with bauxite rocks through it so hopefully she can find some old cartridges and coins to get started.

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grubstake said:

Sounds like she'll be off to a good start. Here's my detailed tuning procedure to help you both get it running properly:
https://www.prospectingaustralia.com/threads/garrett-deepseeker-a-d-s-no-audio.42178/post-677895

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grubstake said:

Sounds like she'll be off to a good start. Here's my detailed tuning procedure to help you both get it running properly:
https://www.prospectingaustralia.com/threads/garrett-deepseeker-a-d-s-no-audio.42178/post-677895

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d1010223 said:

Grubstake, after a balance would you still leave ‘auto’ switched on?

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grubstake said:

Always, because it isn't auto ground balance - it just automatically restores the threshold level set by the user. Ground balance is wholly manual and needs constant adjustment when nugget hunting in mineralised ground.

Both the Groundhog and the Deepseeker are much easier to handle when hip-mounted, because of the need for frequent ground balancing. Fortunately, this soon becomes second nature to the operator.

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d1010223 said:

Sorry to bother you again but do you do the adjustments in your procedure while in auto? The garrett sheet online suggests holding the switch left and right and adjust in both vf/tr but seems to suggest doing the adjustment while in manual vf mode?

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grubstake said:

For your own sanity, I think you'd be wise to ignore the Garrett instructions. Garrett were clueless about the real world prospecting usage of these detectors and it took experienced Aussie prospectors to find out how they worked best in our mineralised soil conditions. As stated in my linked procedure above, "Flip the handle toggle switch to the left, to ensure VLF mode is engaged. Forget about TR mode - always use VLF."

I learnt this lesson the hard way, because I was still living in NZ when I got my first Garrett Deepseeker in 1979 and I couldn't figure it out at all from the manufacturer's instructions, despite the fact that I was already experienced with using a Whites 5000D. It took a chance meeting with a successful Kiwi prospector who'd returned home from Perth to visit his parents and showed me the ropes, which took him all of 5 minutes. After that, I was off and running.

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d1010223 said:

Now when underway in auto with vlf does she need to flick the vlf switch at all periodically to reset balance or just retune the pots if you notice excess noise?

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d1010223 said:

And when she has to ground balance while moving around just leave in auto and vlf then set the two pots till just right?

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grubstake said:

Flicking the VLF switch on the handle (I believe Garrett call it the Master Switch), isn't necessary unless you think it may have been accidentally bumped across to TR mode.


I'm not sure which "two pots" you mean? If it's in Auto and VLF, the only pot that needs adjusting while detecting is the 10-turn Ground Balance. How often that needs changing will depend on how mineralised the ground is. If swings are getting noisier or you're in doubt, pause swinging and 'bounce' the coil up and down a few inches while turning the ground balance one way or the other to get back to a stable threshold tone.

All this becomes second nature after a little while, as does listening for a signal. With practice, you soon find yourself operating in auto-pilot, relying on your brain to let you know if it picks up something different in the sounds that needs attention as a possible target. Meanwhile you can look at the scenery, watch birds, dodge spiderwebs, think about which direction to move next, etc.

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