Gold Bug 3.5" Round Search Coil

[Bohemia Miner 84]

On 9/25/2020 at 10:07 AM, Steve Herschbach said:

Once I get the detector back I'll do something up. But I have used this detector and coil combo before and there are limits to what a small coil can do as far as enhancing small gold capability. The machine itself has inherent limits. However, nobody has compared the original Gold Bug to the modern digital version. Since I just happen to have a new 19 kHz model on hand, I will test them both on tiny nuggets to see just what the difference is. I believe it will be instructive as people tend to focus just on frequency, but there is more to it than that.

I was selling at the Portland Oregon GPAA show a few years back.  A man came up to me looking for a Gold Bug.  I showed him Fisher’s latest offering to which he replied “No, I’m looking for an Original, without the Screen”.  I explained to him that they were few and far between.  I then inquired as to the reason for his search and dislike for the newer model.  Both were 19kHz.  Both had Ground Balance capabilities with the new “Bug” more user friendly.  He then told me the following story.  He and a Buddy were out Nugget Hunting.  He had the original and his Buddy was using the current model.  He then pulled a good-sized piece of Magnetite out of his pocket with a piece of gold attached.  His Buddy’s detector showed it as being ferrous so he failed to dig the target.   He was following behind and because the “hit” was so solid and with nothing to tell him otherwise, he recovered it!

I had never seen anything like that although I’ve been told that both were created by the same Hydrothermal activity. I wish I had snapped a photo!

[EL NINO77 1,396]

 ...it could also be the use of a small small concentric coil in an older gold bug ....  because the  suficiently small concentric coil can excellently detect surface non-ferrous metal even on a strongly mineralized substrate ... very often much better than the coil DD ..

...That's why I'm very interested in Steve's comparison of the 3.5 "concentric coil on the Old Gold bug and the 5" DD coil and the new Gold bug pro.

[snakejim 110]

On 9/23/2020 at 3:50 PM, Steve Herschbach said:

The main thing I wanted, however, was to get the detector tuned for the 3.5" coil. Most people do not know it, but analog Gold Bugs are hand tuned for every coil. The coil they ship with is tuned for the detector, or should I say the detector is tuned for the coil. Accessory coils may or may not be a perfect match if the original coil is swapped out for something else. Long story short is I am asking them to match the detector to the 3.5" coil as well as is possible.

Steve, I have the Fisher Factory repair manuals for the Motherlode 660 and the original Gold Bug. I did repairs and mods on a few of the Gold Bugs for friends. Even built a water proof one in a 1280x box. The tuning of the coils is covered in the manuals and a Ferrite sample was provided. You can have them if you want them.

Best wishes!

snakejim

[Steve Herschbach 33,513]

thanks Jim, very kind of you! PM sent.

[Tom Slick 500]

Steve, You wouldn't happen to have any Info on the Tesoro Diablo Gold Demon produce from 8/88 - 8/91? I have a nice one hanging in the garage. Any info would be much appreciated.

Thanks

Tom