EPE resistivity logger

[homefire]

Crazy levels of CHEAPNESS ! Wish there was stuff like this when I was a kid, eaaa? You could even Bluetooth or WiFi.
https://www.banggood.com/search/arduino-sd-card-module.html

[RS_Phil]

I try this both in PIC16F876A or 876 both work correctly, but i had some experience in the type of LCD i used, which display some character
which I don't understand.

[ivconic]

I try this both in PIC16F876A or 876 both work correctly, but i had some experience in the type of LCD i used, which display some character
which I don't understand.

At the time i was not ready to investigate what's exactly the problem. Those chips were available and cheap, so it was less annoyance simply to replace one with another.
But i also had series of misty happenings on LCD with "/ISP" version. While nothing similar ever happened with "/04" version, at several builds.
So i can only assume ... endlessly ...

[Prospekteur]

Can someone help me, how to connect the S9 pin. S8 pin and the T.P. pins. What to do with them and for what reason are they good for? Didnt find the answer in beckers paper......



.......update: S9 and S8 are clear now;-). Only this T.P. pins are mysterious.......Did someone know, what to do with this T.P. pins?

[ivconic]

Can someone help me, how to connect the S9 pin. S8 pin and the T.P. pins. What to do with them and for what reason are they good for? Didnt find the answer in beckers paper......



.......update: S9 and S8 are clear now;-). Only this T.P. pins are mysterious.......Did someone know, what to do with this T.P. pins?

Goes down to the right on "RA4". S9.
TP pins are "Testing Points" pins.
Leave them as they are.
By now don't worry on those.

[Prospekteur]

Thanks Ivconic��.

......The Epe does work now. Only problem for now is, that the "A" value on the screen shows always "max". I didnt find out what causes this problem. Also I have to check if download does work. But first i have to find out why " A" shows "Max". But it seems that i can get this great unit to work properly in the future.......

[Prospekteur]

Here are some pictures of two problems i have.

1. the display shows always the "A" (opamp) value as "MAX" in the test mode. In operation mode seems to work correctly? The images are taken with probes in the air (no soil). See pictures......one image in test mode and the other in operation mode......

2. Ive get a old Pcb where a track on the upper left of the pcb is cutted, also there is a cable beneath that soldered to a resistor. I dont know where to connect this cable.......can someone help me please. Also see the image....(p.s. i have meanwhile cleaned the pcb.....looks much better now, as on the image;-))

[Prospekteur]

Ok, I know for what this red cable is for. Its for the current monitoring addon from beckers paper. Only thing wich is not clear now, are that the lcd showing this "MAX" letters instead of the "A" values (see images above). Could this have something to do with the current monitoring addon (will check this addon tommorow, it must be activated with push button combos) ? Or is this normal, because ive seen the "MAX" instead the "A" values on several images of homemade EPE which the A-value is "MAX".......so could this be normal?

[ivconic]

I can't recall so i had to "consult" my archives...
Here is how it looked like on one of my builds;

[Prospekteur]

Hi Ivconic,

thanks for your great help. I know the design of your EPE;-), I think Ive seen every image in the internet that shows an ERL;-) Your ERL looks so great and professional!!!

Meanwhile ive found the problem. Its the current monitoring addon from beckers paper. Ive managed to solder the cables on right position and activated the "mode", "save" combo. Now everything works fine. My Lcd look exactly like yours. Im so happy now!!! I will add a piezo buzzer to it, to have a signal when using the buttons. Also I have to activate the light of the lcd. Do you have the option to changing between 9 Volts and 12 Volts on your board. Im thinking about to add this option too;-). Do you have some results from a outdoor project......?

[Prospekteur]

First image from my epe resistivity logger...........not ready yet;-). Waiting for some banana plugs and long cables..........

[ivconic]

Personally i have not used resmeter too much in surveys, only testing in process of finishing it.
I made few of those by order, for other people.
Yet i remember that one of those did great job with it. He is professional archaeologist and he knew exactly how to handle it.
So few months later he sent me the record. I was amazed! Couldn't believe what he achieved.
It was pretty clear "picture" of the underground facility dating from ancient Roman era.
But to be able to achieve that; he made several thousands records on the same matrix.
I will try to find that record in my archive and if i find it; i will post it here.
...
Looking at your photo i see that you did it pretty well.
I would like only to point you on one thing, i marked the detail with red circles.
It is the most delicate and critical part. Washers are too close.
If there is a high moisture in soil; it may make occasional "junction" between washers and produce false readings.
Try to replace washers with something else.
Next thing; the "peaks". Try to make them more conical and very "sharp".
Because once i stepped on pretty dry soil and had lot of problems to stick those properly.
Stepping on them hard on dry soil; may produce whole setup to take a part and break.
Later on i replaced the "peaks" with stainless steel ones, sharpen to the "needle tip" at the ends.
Here is the good hint; use the stainless steel axis from some scraped computer printer!
Those are very hard and strong. And easy to be sharpen with sanding machine.

[ivconic]

I have found only one segment of the record i mentioned:

[ivconic]

I also founded in archive one of my previous construction.
This one was quite good on dry soil.
Welded "triangle" is the base. Pretty stiff and strong.
Observe the peaks and tips:

[ivconic]

Another hint; the length of the peaks.
I put 30cm length.
Always trying to maintain that 25cm are in soil.
Longer the "contact area" = more accurate and stable readings.