So I wanted to go back to my favorite beach since this time I would hit it at low tide. Not a great low tide, but enough to expose a good stretch of wet sand where I am dying to try the Tone (and Mute) modes where there is a decent amount of iron present. Today was not that day. Completely sanded in so I will have to wait until this beach gets ripped up a bit. It does not help that they groom the beach every morning. Last time the grooming guy came out of his way to circle me, trying to intimidate me into leaving I heard almost no iron, so I knew it was deeply hidden. 2 1/2 hours flies by and I'll probably have to wait until my good season hits this fall. I guess I'll have to cough up some cash and buy that Xtreme scoop so I can maybe hit some lakes with it. I'm not strong enough to handle those rough waves at these exposed beaches like you veteran water guys are The surfing dudes will be scraping me up out of the water. I'm not disappointed in the machine, just in the beach conditions and of course the short time allowable to hunt.
By Steve Herschbach
First off, I want to point out that what I am about to describe is not uncommon with high power detectors that have a coil that can be disconnected. The only way to really eliminate the problem is to hard wire the coil, which is another reason for why this option is chosen by so many manufacturers of underwater metal detectors. The White's TDI Beachhunter is a good example. The problem has its root in coil capacitance and the high voltages involved, and the difficulty of getting good shielding using a removable connector.
If the Impulse AQ is submerged halfway, so that the water level is anywhere in roughly the area indicated in the photo below, you will get continuous false signals. Just holding the unit stationary in the water at this level will cause signals as the water moves around the connection area. If you are not aware of what is happening it is every easy to mistake this for electromagnetic interference (EMI).
The problem is worst in the Tones mode, which I just happen to be using a lot. It is accentuated by a short pulse delay, high sensitivity settings, and low ATS settings. If you want to reduce the false signals, here are some solutions:
Use the All Metal or Volcanic modes instead of Tones Increase the Pulse Delay to 9 or higher Reduce the Sensitivity to 4 or lower Increase the ATS to 8 or above Or some combination of the above.
In practice this only occurs when wading, and only at a certain depth. My solution was simply to stay either deeper or shallower. This does leave a strip or area unhunted. You can either switch the settings as suggested above, or do something to change the height. Like hunt that strip with mask and snorkel, for instance.
Anyway, hopefully this is put in the manual as it is something inherent in the operation of the detector, and can drive you nuts if you run into it and do not know what is going on. It took me several hours of detecting to put two and two together, and it was then confirmed that yes, that is the way it is.
By Joe Beechnut OBN
Early on I see the Halo of targets in the threshold of the "AQ" doing airtest..... so I've been playing with the settings to see if I can pull up more of the audio of them when out hunting in the water. Jim and I have hunted together before, a very good "old beach" hunter.
Video of those changes in the threshold Jim speaks of....
By Steve Herschbach
Here are my latest digs in the water at Tahoe. Things were going great until the handle on my old scoop finally gave up the ghost. Can't complain, it served me well, but not like you just run to the store and get another. I'll have to make one.
Anyway, I have to admit at this point I am wondering where my first gold ring with the Impulse is at. Popular beach, tons of people in the water for many years, plenty of targets... no ring. Maybe somebody is running a magic detector here that finds gold rings while leaving all the aluminum tabs and nickels behind?
I'm actually very pleased with this mix of trash. Exactly what I expect to be finding, but getting it pretty focused, good ratio of ferrous to non-ferrous. I’m digging tight signals that have a little depth to them. Generally ignoring boomer targets and surface double-blips, though a few surface targets got dug just because they were so easy. It's mostly bottle caps and large ferrous faking me out, but not so much as to bother me. I expect a certain amount. Anyway, I need to get a new handle made up so I can get back in the water tomorrow. Best find - a Buffalo nickel, can't read the date so far. The item in lower left is a corroded zinc penny.
I’m in thick magnetite sands with lots of rock. Hunting tones exclusively, 7uS, sensitivity to max, ATS and reject at preset.
Fisher Impulse - the non-ferrous
Fisher Impulse - the ferrous
Broken scoop handle