Bench and Field Testing the "Gold Bug Pro" (Part 3)

(Fisher's "Gold Bug Pro.")

Ideal Conditions

I conducted my bench testing of Fisher's "Gold Bug Pro" outside my home in very lightly mineralized soil. All of the tests were "air" tests, meaning none of the target placer gold pieces were buried. Instead, I taped them to a thin piece of cardboard which I then laid on the ground.

(Note: All bench tests were performed using the "GB Pro's" standard 5" nugget coil. J.R.)

Yes, I know this represents testing the "GB Pro's" abilities under ideal conditions. Truth, be told however, I wanted to see what my machine could do under those exact conditions to get an overall idea of its sensitivity to small pieces of placer gold. I figured my field tests would then provide a good comparison of the machine's abilities in less-than-ideal conditions.

(The smallest piece of placer gold I used in bench testing the "Gold Bug Pro.")

Easy Ground Balancing

In the photo just about this paragraph you can see the smallest piece of placer gold I used in my bench testing. This is a moderately thin flake just about as large in diameter as the flames coming from the torch on the back of a common U.S. dime.

Ground balancing my "GB Pro" in lightly mineralized conditions was a breeze...I simply pressed and held down the ground balancing touchpad button and pumped the coil up and down a few times and bingo! I really think the way the ground balancing works on the "GB Pro" is a big improvement over the constant fiddling with dials you must do when using the "GB 2" (meaning no slight to the latter machine which I've used a number of times out in the field).

No Loss in Sensitivity

I was consistently able to detect the small flake of gold at 3"-4" in "All Metal" mode (air testing). The two-digit target numerical indicator on the "GB Pro's" display correctly identified the target as gold about 80% of the time. In "Discriminate" mode there was no observed loss in detection sensitivity and the target was correctly ID'd as gold about 95% of the time.

(This nugget was the largest target used in my bench tests.)

On larger, heavier targets like the placer nugget pictured above, the "GB 2" was able to consistently detect the target at around 10"-12." I also bench tested the "GB Pro's" abilities on two other placer gold targets, a large flat flake and a smaller, but very dense nugget. The results were very encouraging on these targets as well.
Although I was swinging the "GB Pro" under ideal test conditions here, I was still very impressed with this light-weight, easy to use gold detector. Still, the proof of the pudding would be found out in the field.

There's more to come...

If you liked this post, you may want to read: "FREE EBOOK! Where to Find Placer Gold (List D)"

(c)  Jim Rocha (J.R.)  2012

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