It's just the signal generator which has a higher output level with a sine wave than a square wave....it's kitset from d*** Smith/ electronics Australia, K-7340.
The interesting thing driving it with a square wave is that when you break down a square wave into it's components, it's all the odd harmonics up to infinity at decreasing signal levels, all added up together (we learned all that stuff a school at 13 or 14).
So going backwards and doing a downwards sweep from 11KHz, the first resonance is at 3.7 to 3.8KHz, roughly 1/3 of 11.0 to 11.6
The next is 2.2 to 2.3KHz. 1/5 of the frequency, the next is 1/7 which is 1.6 ish KHz.
So , take a 1.6KHz square wave.........
The fundamental is 1.6KHz
The 3rd harmonic is 4.8 KHz.
The 5th harmonic is 8KHz
The 7th harmonic is 11.2 KHz.
It's the 7th harmonic of a 1.6KHz square wave which excites the sensor.
Switching to a sine wave though, none of those harmonic frequencies are present, so you only get a response with a square wave, which is what you get with a shockwave (knock) anyway, which is how they work in a real situation.
No correlation at all with bore size either........it's all bullshit.
Going through some Mitsubishi part numbers E1T15571 through to E1T15579, they're all knock sensors but different tuned frequencies from different engines.
E1T15576 is what comes on a 3.5 DOHC about 11.2KHz
E1T15579 comes on a GDI 3.5 Pajero...it's 7.5KHz.
The bores are the same size but the pistons are completely different.
But......it's the internet.
quote from barryboys.
Yes, yes, yes, that might be so, but you're clearly missing the bigger picture.....