First step: treat the wall like a mystery novel. Pull out a handheld RF spectrum analyzer or a smartphone app that can log signal strength. Point it at the mural and note the baseline in a clear spot. Then, without being too dramatic, move a meter closer, keep the probe flat against the paint, and record the new reading. If the signal drops noticeably under the paint, that’s your clue. Next, use a thin, flexible antenna probe to “dig” down. It’s a cheap, wide‑band probe you can attach to a cheap transceiver. Slide it just under the outermost layer of paint—if you can, use a small screwdriver to lift a corner of the paint or a drop of solvent to expose a bit of the surface. If you see a sudden spike in attenuation or a change in the frequency response, you’ve located the hidden jammer. If the paint is a thick, oil‑based layer, you’ll need to use a multipath‑aware scanner. Turn on the “near‑field” mode if your device has it, sweep across the mural, and watch for “nulls” or dips that align with the paint’s pattern. Finally, document everything. Keep a spreadsheet of coordinates, paint thickness (if you can measure it with a caliper), and signal level. The pattern will emerge once you cross‑reference the dips with the paint layers. So, in short: probe, compare, lift a tiny sliver, and repeat until the ghost signal reveals itself. If the paint keeps hiding, just remember: the wall is just a layer of interference. The signal is still out there, waiting to be found with a little persistence and a lot of patience for the machine.

That’s a poetic way to look at it, but don’t let the colors distract you from the numbers. Keep your pen ready to jot down the exact frequency and strength each time you hit a new shade, and if you notice a spike when the paint turns cobalt, flag it as a potential resonant layer. Remember, the wall is still a medium of attenuation; the colors are just the icing. So scan, note, and let the data guide you to the ghost jammer. Good luck, detective.

Sounds like a plan—keep your notebook open and your spectrum analyzer steady. When that cobalt dip pops up, just log the frequency, drop, and any visual cue. Then you can map the “secret signal” layers without getting lost in the art. Happy hunting, and remember: the signal doesn’t care how pretty the paint looks.