LOOKING FOR GOLDSCAN 4 Schematic.

[ABDW9]

Hello ABDW9
This is the way I set my GS4 and works well:
Do you have to be a leg to adjust RV5 U13 at 0 V instead of the leg 7?
"Yes !!!"
Adjusted R8, to 0 volts on pin "6" of 5534, with the coil connected, away from all metal.
All adjustments in position 2, "all metal", follow the steps outlined above in post 102.
After adjust RV7 to 0 Volts in pata "8" of U13 C, Change SW1 in position 1, "OFF", and adjust RV6 to 0 volts again in pata "8" of U13 C.
Check iron rejection mode is "SELECT 1" No. 3 of SW1.
Prepare a video later.
regards
Jose

Thank you my dear brother Jose
I've been in a hurry something
But I realized that I should be a little bit slower Instead of Ask Ali Mrajat a all previous settings even harder on something you'll ask
Please excuse me
'll Try to review all previous settings
I and so far has reached the stage quite a bit
Thank you brother Jose
Regards Abdo

[Jose]

ABDW9
Sorry, do not understand the question, please try again in a timely specifying each question.
Regards

[ABDW9]

Hello Jose
Now only key "RESET" just is not working??
.......................................
All the problems that I have a solution
Thanks Only Jose

[petoco]

Hello Jose,

I just finished mounted the GS4 every thing goes ok, but when I made the test in my house when I swept the search head one side to another it made a fake signal, like when it find a metallic object, if I put on the floor the detector stabilized well if not a reset and it work properly. I ask to you because I read in your post 150 i think, you faced this problem too? you manage to solve it. I am trying several things but cant fix it, I thing the problem is in the coil and I would like to try your double coil on post 171, but I don´t know what is RG59, it refer to the circuit conection? another question is if you eliminate R14 or not?.

Thanks in advance

[Jose]

Hello Jose
Now only key "RESET" just is not working??
.......................................
All the problems that I have a solution
Thanks Only Jose

Check the PCB that the "D" of J113 in both channels are connected to GND.
Jose

[kt315]

it is not D/Drain of J113. I see S/Source transistor pin on the schematic you marked. Drain pin is above.

[Jose]

KT 315
In post # 4 you could see in this way the location of the drain and source.
Anyway, Geotech forum members, saying that small signal configurations as in this case, drain or source can be connected either up or down.
Regards

[kt315]

ooh main God... why you so are disliking the electronics...

[Jose]

Hello Jose,

I just finished mounted the GS4 every thing goes ok, but when I made the test in my house when I swept the search head one side to another it made a fake signal, like when it find a metallic object, if I put on the floor the detector stabilized well if not a reset and it work properly. I ask to you because I read in your post 150 i think, you faced this problem too? you manage to solve it. I am trying several things but cant fix it, I thing the problem is in the coil and I would like to try your double coil on post 171, but I don´t know what is RG59, it refer to the circuit conection? another question is if you eliminate R14 or not?.

Thanks in advance

Petoco
RG59 coaxial cable is connected between the coil and the detector
R14 and R79 are 1K, 500 ohms in paraleo way, you can remove and place a resistance equivalent.
The final value of R buffer (R14 and R59) depends on the type of coil.
The spurious signal in the coil, can be caused by inadequate shielding.
You may also minerals in the soil, brick or ceramic.
Try detector in the field and see how it behaves in different terrain.
Regards

[Jose]

KT315, from the point of view of Fet electrical symbol, you are right.
We would have to see if it was error to draw the diagram, sketch on paper.
Jose

[ABDW9]

Check the PCB that the "D" of J113 in both channels are connected to GND.
Jose[ATTACH]24235[/ATTACH]

Hello
Brother josie you beautiful greetings
I have searched in connection j113 and grandmother fully connected
Congratulations I wish you.

[porkluvr]

KT 315
In post # 4 you could see in this way the location of the drain and source.
Anyway, Geotech forum members, saying that small signal configurations as in this case, drain or source can be connected either up or down.
Regards

Some manufacturers will tell you if a particular JFET has interchangeable S & D. Other manufacturers will have the "identical" part number but their data sheet will say nothing about S-D interchangeability.

For instance, the Philips (NXP) and Fairchild data sheets, state "S & D are interchangeable" for the J111~J113.
Vishay's J111~J113 spec sheet, however, makes no mention.

Another way of stating S-D interchangeability is "symmetrical".
Not all JFETS are symmetrical. Do not assume that all JFETS are symmetrical just because some of them are.

2N4393 looks like it may be a good sub for J113 and Fairchild's 2N4393 datasheet does state S & D being interchangeable.

EDIT: So, what this all means is that if you are doing a PCB layout and run into a problem with a J113, you can sometimes side-step the issue by making a pin-swap.

You can get an ohm-meter and measure from G-D and G-S and you should get identical readings. Same with a diode test.

[Davor]

BF245 is by definition a symmetrical one. It is easier to find it here than the J parts.

When mentioning the diode test, next time check the barrier voltage ... it is lower than the usual silicon diodes, as they are not doped as much. May come handy sometimes.

[Jose]

Davor and Porkluvr Thanks for clarifying these issues.
ABDW9, if you have oscilloscope check the noise level at the output of 5534, with the coil disconnected. If noise is high for some reason, the detector becomes unstable and impossible to tune.
Best Regards
Jose

[alonejax]

hi to all

any body make gold scan 4?
what is max sence meter for gold in dept? is a good detector?
thanks