Anyone with even the slightest knowledge of electronics can see that calculator, and the "circuitry" inside the Examiner, do nothing useful. Calculators, in general, do have a fixed-frequency "clock" signal that runs the calculator circuitry, but the frequency is not altered by any key strokes. So the claim that the calculator provides a signal with a programmable frequency is false.
The web site goes on to claim that the calculator couples to the circuitry inside the black box via induction, with the meandering piece of wire as the primary side of the "transformer". But this piece of wire is not connected to anything, and therefore is not part of any closed circuit, and cannot possibly support inductive coupling. Because there is no circuitry either inside the calculator, or inside the black box, that could operate as a transformer, Ranger appeals to Tesla in an attempt to explain away the obvious lack of any real induction mechanism. So, the calculator taped to the top of the box cannot possibly relay any "signal" to the inside of the box.
What about the rest of the circuit? It's just a few odd components soldered together to appear "technical". The claim that the components form some sort of resonance circuit which is somehow tuned by the numbers punched into the calculator is false. The silliness of this claim is underscored by Ranger's insistence that, once again, the circuit is of the "Tesla" variety, and not understood by normal science. Such statements are the norm in all sorts of other pseudoscience, and a sure sign that the claims are bogus.
In RealScience, a resonance circuit would never include a series diode, which would specifically block resonance from occurring. And, in RealScience, resistance is the mortal enemy of a resonant circuit, yet Ranger has two pots in the loop, which add up to a whopping 12.4k-ohms. Pretty much guaranteeing that, even if the diode is removed, there ain't gonna be any resonance. But, again, even ignoring the fact that the circuit cannot possibly resonate, the notion that numbers punched into a disconnected calculator will change the tuning of a fixed-component circuit is just plain quackery.