Harmonics

[Mark-VA]

Since posting the visual transmit frequencies of the XP Deus 2 I've had feedback that I need to include the harmonics that are also produced by the main frequency. I guess people are complaining and stating the Deus 2 should transmit many frequencies, but I can only find 2 with substantial amplitude to be of any use.

"Harmonics are defined as an unwanted higher frequency component that is an integer multiple of the fundamental frequency. Harmonics create a distortion in the fundamental waveform. Harmonics usually have a lower amplitude (volume) than the fundamental frequency."

So, is there any reason in trying to pick out a particular harmonic frequency to include in useable transmit frequencies?


Page 43 in user manual.
"Simultaneous Multi Frequency (40dBua/m at 10m) or between the 49 single frequencies from 4 to 45 kHz"

[Skippy]

I think it's unlikely the D2 will make use of any harmonics.
Perhaps your 'feedback leavers' have memories of the Fisher CZ range ( CZ-3 ,CZ-7, CZ-21 etc ) of machines, which DO use the first harmonic in their signal processing. Specifically, they transmit a 5 kHz square wave, and receive/process the 5kHz fundamental, AND the 15 kHz first harmonic. The amplitude of the 3rd harmonic is 1/3rd ( one third ) that of the fundamental, which makes it more prone to noise, and limits the use of this technique.

[ivconic]

I think it's unlikely the D2 will make use of any harmonics.
Perhaps your 'feedback leavers' have memories of the Fisher CZ range ( CZ-3 ,CZ-7, CZ-21 etc ) of machines, which DO use the first harmonic in their signal processing. Specifically, they transmit a 5 kHz square wave, and receive/process the 5kHz fundamental, AND the 15 kHz first harmonic. The amplitude of the 3rd harmonic is 1/3rd ( one third ) that of the fundamental, which makes it more prone to noise, and limits the use of this technique.

It's funny you brought that up!
Around the beginning of the '80s (1982 I think) the Loube brothers bought their first detectors and became hobbyists.
I once read somewhere that their favorite model was the Fisher 1265 (like mine too and to many others too).
15-17 years later they made their first model; Adventis. In an aluminum case.
I had the opportunity to see one, although nowadays they are very rare, hard to find.
A couple of hours of "playing" with it in the field... I couldn't shake the impression that it reminded me of the Fisher 1265 in its behavior.
Even the operating frequency was the same.
Of course I have no evidence for what I am about to say, this is just a mere guess; but personally I think they "moved" the Fisher 1265 into the digital domain.
Of course, this is not an easy task, it also requires enviable knowledge and familiarity with electronics and technology.
Anyone who thinks plagiarism is easy and simple; it's terribly wrong.
Especially if it's not just cloning but taking the story to a higher level.
Adventis in aluminum housing was far ahead of its time in terms of its performance. I was blown away by the "depths" I saw with it.
Therefore... it is not impossible that they are developing their XP technology and brand; followed the development line of Fisher, that is, some ingenious solutions found by the Fisher team headed by Dave Johnson.
When you move a completely analog project and idea into the digital domain;
1) It is impossible to prove plagiarism
2) New opportunities are opening up for you brought by new technology, in the form of improvements, upgrades, new functions...
3) Over time, money arrives, the company expands, you employ young smart people, create a real brand and create new models.
But... the "roots" and previously drawn directions are still respected in outline.
Why give up something that was once thought up by someone ingeniously?
This doesn't have to mean anything. But it is a good story for history.