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Long story short, yes, cell phones do interfere with metal detectors. Actually, any electrical device could do the same including your pinpointer and your friends’ detectors.
But, it depends on the phone and on the detector. This means that interference between the two devices doesn’t always happen.
Metal detectors are more and more sensitive. They can detect smaller and deeper objects. But this means that they are more susceptible to interference.
Detectors are by nature susceptible to interference because they are made to detect buried metal using electromagnetic fields.
And, cell phones, like any electronic device, have electromagnetic fields. So you could get false signals because of it.
The larger the coil the more likely interference would happen. DD coils pick up interference more than concentric ones.
How to stop the interference?
If the metal detector chatters, the first thing to do is to find out the cause of the false signals.
This step is important to avoid sending the metal detector for repair while in reality there is nothing wrong with it. And you need to diagnose any problem in order to fix it.
Anything that has an electromagnetic field (and the phone is one of them) and any metal object could be the reason behind the interference.
Metal detector and phone interference
If you go metal detecting alone, it‘s a good idea to bring your cell phone with you just in case. However, it may interfere with your metal detector.
To deal with this problem you can choose one of these options:
- Simply turn the mobile phone OFF
- Put it on airplane mode
- Put it in your back pocket
- Leave it in the car if this safe and you think that nobody will break in.
Standby mode isn’t enough because cell phones are always communicating with the towers around them.
I think you’re familiar with the wired noise a speaker or radio makes because of a nearby phone just before it rings.
False signals caused by the environment
Highly mineralized soil and ground full of trash will cause false signals. You can either adjust the sensitivity and the ground balance or go to another spot.
Power lines, electric fences, thunderstorms, telephone lines… all of this could cause interference.
Avoid using the metal detector inside the house because there are many electrical devices, electric cables and metal objects in the walls and on the floor.
Interference with other devices in proximity
Sometimes, the pinpointer could interfere with the metal detector even if it is turned OFF and even if you keep them few feet away from each other.
To solve this problem, some brands say that they have interference blocking technology. Some call it Detector Interference Free (DIF).
I don’t know who it works exactly. They say that it disengages the coil’s magnetic transmission.
If you are hunting in groups keep a distance between each other. Metal detectors could interfere with one another.
The metal detector itself
Higher sensitivity means that smaller and deeper objects could be detected. But, when you are increasing the sensitivity, at a certain point, you will get false signals.
So it’s time to decrease it slightly until the false signals are over.
Ground balancing is adjusted automatically in most metal detectors. But for the advanced devices, you can adjust it manually. Do that to stop the false signals.
The entry-level detectors have a fixed frequency. But in more advanced models, you can adjust it.
Use this feature to make the metal detector operate at a different frequency than the other devices.
Metal detectors have many discrimination modes. The interference is, usually, easier to control in the all-metal mode aka the zero discrimination mode.
Make sure that the search coil cable is wrapped snuggly around the shaft and it’s securely connected to the control box. If the cable is flapping around, you will hear false signals.
If you are using a search coil cover, make sure it’s clean and there is no water in it. This may cause false signals too.
Check the batteries, usually. A metal detector can keep running until the batteries are completely dead.
But in some cases, you can hear some unusual audio signals. Replace them. Alkaline batteries are recommended.
If you checked everything and you are still getting false signals, you should send the metal detector for repair to see what’s wrong with it.
The interference between mobile phones and metal detectors do exist. You can simply turn it OFF, put on airplane mode or put it in your pocket or in your car.
But you have to know the phone is not the only source of interference. It could be your pinpointer, your friends’ detectors, power lines…
Tell me in the comments below which one of these tips was helpful to you.