Detectorists
G'day
First things first, there are coin and relic detectors and there are gold detectors, two different technologies, neither detector can effectively do the job of the other as both types have their strengths and weaknesses.
Coin and Relic detectors, the Equinox falls into this category irrelevant of whether is is touted to be able to be used for gold prospecting as some are, it is what is known as a vlf detector, while it may function marginally in mineralised soils it will lack the depth and ability to work some ground types effectively, this is the very same reason the introduction of the pi detectors was so dramatic in the 90's, vlf detectors are great for benign soils, soils of low mineralisation and magnetics like you would find in the suburbs so they are very good at finding things lost in parks and on the beach, and the strength of the vlf is that they have an effective descrimination abilty so that they can be run to ignore ferrous junk items that also litter these areas where most of your valuables like coins and jewelry would be found.
Some vlf machines sold as gold prospecting detectors are good for very small gold but have medium depth ability , they can be used effectively in some areas but these also can struggle in some places where even pi high end pi machines can be problematic, machines like the minelab gold monster and fisher gold bug are a couple of them, I have found in some places where I have tried these sorts of detectors, by the time you get them stable and quiet enough to use basically all you will find is surface or very shallow targets, many people carry these as well as a pi detector but also have to choose the area that they can use them in but as for having it as your main detector don't expect to get deeper targets with them.
Pi (pulse induction) detectors like the older minelab Sd or Gp detectors will perform better in goldfields soils and will have better ground mineralisation handling capability as they were designed for this purpose, they can also struggle in some places compared to later pi Gpx models, but they will still out perform a vlf detector depth wise on most ground, also you have to realise that these days most of your targets are deeper as most of the places you will access will have probably been well worked over with all types of detectors, the weakness of the pi detector is that the early pi detectors don't have any descrimination function but the later ones do even though most people will never use the function as its not very reliable and best left switched off, hence the rule of dig everything until you know what it is.
If you are wanting to chase gold in my opinion you would be better off with a pi detector even if its an early model one like the Sd than to try to do the same with any vlf machine, I have seen it hundreds of times with new detectorists, they buy a cheap detector and end up disapointed with the results and then either give it away or come to realise they have to shell out for a better detector if they want to get gold, its a hard game even with the very latest machines and the gold is getting harder to find so if you want to be successful you have to have the best you can afford and what is the more capable machine that is better suited to the job.
cheers
stayyerAU