My Uniprobe and Tinytec will both pick up smaller links than the ones in your test. I haven't set up a test exactly like yours but I've used mine in real life conditions with success. Most of the main detectors I now use, won't even pick up a small gold link anyway so the argument with me is moot. I'm not going to search acres of land with a pin pointer hoping to find a small gold linked chain. If I use my gold machine and get a hit, my pin pointers will pick up very tiny pieces of gold or any other metal for that matter if I can't find it with the main detector. Usually I just grab a handful of dirt or sand and wave it over the loop of the main machine until I get the handful with the target. Usually, you can then just spot the target without a pin pointer but if not, the pin pointers I use will locate it.