Processes

[Neugene]

I have read the manual and think I understand all it says about the processes available on the F-75.
Does anyone know more about what each process is/does? I would like to know what settings are affected by each process. For instance does the JE mode just increase the sensitivity without you making an adjustment with the knob? What does the PF process do and why is it better for broken or uneven ground than say DE or BC? Does the BC process just notch out bottle caps or is there more to it than that?
Questions like this drive me nuts. The manual is pretty vague with their descriptions and I would really like to have a better understanding of what is going on.


HH

 

[Streak!]

I like to know a bit more too, but the manual is kinda lacking in that dept. I suspect that JE mode jacks up the front end power, but cant find confirmation on that. Usually, the sens only affects the recieve gain, and the actual front end power is unaffected no matter WHERE you put the sens dial. JE may actually affect the transmit power, but without a bit more technical datam its no more than a guess at best. Hopefully Mr. Dankowski will write an in depth article about the 75, and exactly what each process does. Kinda like the one that was written for the DFX. (By Jeff Foster??). I guess till then we will just have to stumble through it!!

 

[erikk]

Looks like the manual was thrown together late Friday night as second thought prior to shipping. Don't tell me 5 pages of detecting activities-tell me how and why to make it work properly .02

 

[Neugene]

I Agree. I am curious does anyone from First Texas monitor this forum?

 

[Jackpine Savage]

Haven't used the F-75 just the T2. Changing the disc setting on the T2 and F-74 in DE mode has a direct affect on sensitivity levels. Some have noted a few disc level settings where the sensitivity increase is obvious..there are more. This is built in for a reason and they (the engineers) will not talk about it. Its something they do not want the competition to copy!

Perhaps JE mode bypasses the steps in sensitivity as you change the disc and runs it more "full bore". Hell, why not have it all when you can use it!

Tom

 

[Neugene]

I design materials testing equipment that functions on the NANO scale (read one billionth of a meter). I only mention this because it has bearing on this topic. Our technology is proprietary and as far as I know there is no other company that has succeeded in making it work. I am still able to discuss the way in which the machine functions in quite a bit of detail without worry.
My point is that the manual is too vague in places, explaining the different processes is one of them. It should be possible for them to give a better explanation of this without worry of losing their edge over the competition.

 

[Charlie P. (NY)]

This is a W.A.G.

My electronics background was in vacuum tubes and single transisitor circuits, so I have little practical knowledge; but logic circuits and electrons haven't changed in that time so I'll take a shot at what the four F-75 pre-set processes might actually do.

If it was a multi-frequency unit I might suspect they had automated the characteristics of a graphic equalizer and enriched the frequencies within specific bands or regions that favored the desired targets. It's a little less obvious for a single frequency. The choices are default, jewlery, bottle cap and plowed fields. And, from the instructions, these "masks" only effect the audio circuits. The manual states the detector's VDI and audio run independantly (so it's like you're getting the benefits of swinging a Minelab Musketeer Advantage and a White's M-6 in the same motion).

Cutting to the chase of what detectors do lets say they simply determine whether a target is ferric or other metal and how well it conducts relative to the surrounding soil. When you look at the processes they can be seperated by what they are attempting to accept or reject. Default we will set aside as flat acceptance at a mid-range through all levels of conductivity throughout the range not discriminated or notched out by the routine settings. So, the jewlery process will compensate to bring weaker, less conductive targets out but at the cost of producing more false signals. The bottle cap will attempt to clip the signals of magnetic targets within the non-discriminated range but at the cost of jewlery and less conductive good targets. And the plowed fields will desensitize the unit to weaker conductivity and ground changes (you're sweeping over disturnbed and uneven ground which equates to wobbling the coil higher and lower over flat ground) at the cost of missing fainter target signals.

The good news is that they will all register the same regardless on the visual so you have the ablity to interpret how the visual and audio interact to decide whether to dig or not.

Again, this is conjecture.

 

[MIG73]

n/t

 

[Jackpine Savage]

It seems to be the same with all manufacturers. A better explanation of the different functions would go a long way toward understanding their detectors and how to best set them up for different conditions. A prime example is the Explorer. There are varied opinions from experienced users on what is the proper way to set that one up.

On the T2, PF mode seemed to me to be a raw data mode with more user interpretation of the audio required. It gives more "iffy signals" and you have to decide based on the audio clues whether to dig or not. I dug a lot of iron chasing iffy signals in mode 1 but, that was my choice! In a freshly plowed field and using proper coil control for the condtions it does work as advertised.

Mode 2 is smoother in iron but will miss the occasional weak signal on iron co-located non-ferrous targets. Not many, but it will miss a few. The additional processing of the iron signal took a little too much "edge" off the iron responses/sounds near the disc setting to suit me. IMO the engineers could have backed off a little bit there. How about a micro-controller that allows a user to adjust to his preference the amount of sampling/processing being done on the iron responses. Hmmm? Would that be even possible?

Tom

 

[Richard@BackwoodsDetectors]

Detectors usually transmit a maximum signal, allowed by the FCC. With that in mind, it is pretty much as Charlie commented on. The amount of "capture" of the return signal is called sensitivity. On a regular detector, when it is swept over the furrows of a plowed field, it is going to "see" different things, some real and some electronically imagined. Knowing that, engineers can remove those signals from the mix and come up with only a target signal in the ground. In the default mode, the recieve is "cleaned-up" electronically and you hear a relatively smooth audio with a variance as the sensitivity is increased. In the JE mode, the cleaning of the audio is close to being left alone so that you hear everything in the ground, especially the smaller targets. Ham radio has been using this technology for years and IMHO, I think this is what they are doing.
Too, with the enhancement of electronics especially in the DSP area, you will probably find more changes in the coming years. By feeding a signal into a circuit, removing the unwanted components and ending up with a clean signal is great. This has been going on for a few years with some detectors but now your really starting to see some benefits of the progress that has been made....Anyway, sorry to ramble...Richard


Authorized Fisher Dealer