1What we found
Fourteen years on sale. Not one blinded test.
No one, the manufacturer included, has ever shown the AML Pro finding a hidden pipe better than chance. Not in any soil, not at any depth.
Read the full investigation →About 41 mW. Wireless-keyboard power.
Sold on “powerful” radio waves that reach pipe twenty feet down. Worked out from their own certification laboratory's measurement, it transmits about what a wireless keyboard is allowed to.
See the working →No power figure in English for twelve years.
The law says the instructions must state the maximum power. Their 2014 manual gives it in German only. Nothing they publish in English gives it today.
See the manual page →When it disagrees with you, twist your wrist until it agrees.
That instruction is in SubSurface Instruments' own operator's manual. It is how experienced locators come back from site sure it found the pipe.
See the manual pages →Sold as “patented”. The patent lapsed in 2023.
US 7,898,456 lapsed on 3 April 2023 for unpaid fees, with about six years still to run. The UK seller still calls it “a patented scientific instrument”.
Read the patent record →Sold for wet ground. Runs on the microwave oven frequency.
2.45 GHz is the band a microwave oven uses, because water soaks it up. The AML Pro is sold for clay, wet soil and standing water.
Read the short version →Their 2014 manual gives it on the German page, 10 mW, and leaves it off the English one. Nothing they publish in English states it today, though the law says the instructions must. Their own laboratory’s measurement works out at about 41 mW, roughly what a wireless keyboard is allowed. Put that next to “twenty feet through wet clay” and you can see why it isn’t there.
2The four articles
3What it is sold on
Every claim quoted exactly as published. The three UK seller claims were captured with full-page PDFs on 24 August 2026.
| The claim, as published | Where | Verdict |
|---|---|---|
| “the radio waves penetrate the surface as deep as 40′ depending on the surface composition” Double the twenty feet the manufacturer itself claims. No blinded validation exists at any depth, in any soil, in fourteen years on sale. | UK seller, how-does-it-work page | No test, everThe proof → |
| “The AML is a patented scientific instrument” US 7,898,456 was owned by SubSurface Instruments from 18 April 2017 and lapsed on 3 April 2023 for unpaid maintenance fees, with about six years still to run. | UK seller, proper-burial page | Lapsed 2023, still sold as patentedThe proof → |
| “Utilizing technology that was developed for lunar exploration” NASA's only lunar radar sounder, on Apollo 17, worked between 5 and 158 MHz. The only lunar radar anywhere near 2.45 GHz is on China's Chang'e-5, which landed in 2020, eight years after the AML Pro went on sale. | UK seller, AML Pro page | No link on recordThe proof → |
| “All-New” FCC certified in March 2012. Fourteen years later the current literature still calls it new. | Current AML Pro data sheet | Certified in 2012The proof → |
4What the technical claims come to
| The claim, as published | Where | Verdict |
|---|---|---|
| “powerful 2.45 GHz ground penetrating UHF radio waves locate PVC pipes easily” Worked out from their own certification laboratory's measurement: about 41 mW. That is roughly what a wireless keyboard is permitted to transmit. | SSI brochure, current | About 41 mWThe proof → |
| “Unlike the deficiencies of GPR, the AML will work in clay, wet soil, snow or even standing water” One document, a few pages apart, says the device is not ground penetrating radar and that its radio waves are ground penetrating. 2.45 GHz is the microwave oven band. Water absorbs it well enough to heat food, which is exactly the wrong property for reaching a pipe through wet ground. | SSI brochure, opening page | Contradicts itselfThe proof → |
| Maximum radio-frequency power, which the instructions must state by law Their 2014 manual gives it on the German page, 10 mW, and leaves it off the English one. Six documents and 481 pages of their website carry the frequency and no power figure. | Not stated in English anywhere | Missing for twelve yearsThe proof → |
| “Both lights will come on then go off approximately every 2 inches” 2.45 GHz has a wavelength of 12.24 cm. Half of that is 6.1 cm, or 2.4 inches. The indicator is cycling with the movement of the operator's hand. | SSI's own published FAQ | It's your handThe proof → |
5Where this stands legally
- Advertising. Under the CAP Code a marketer must hold documentary evidence for an objective claim before publishing it. The depth, the patent and the lunar claims are all objective and all testable.
- Product information. Radio equipment placed on the Great Britain market must state its maximum radio-frequency power in the instructions supplied with it. The AML Pro’s English instructions do not.
- What we are not saying. We do not allege the device is operated unlawfully. Whether it falls in a licence-exempt category at all has never been determined by anyone, and only Ofcom can answer it. Its measured emissions are far below the relevant ceilings.
Why “patented” is not marked false. SubSurface Instruments genuinely owned US 7,898,456 from April 2017. The finding is that they let it lapse in April 2023 for unpaid fees, with about six years still to run, and it is still being sold on it.
SubSurface Instruments is a real company making a real device with real electronics in it. This is not an allegation of an empty box. It is about the claims made for what is inside it, and about a product that people take onto site to decide where to put a digger.