LOOKING FOR GOLDSCAN 4 Schematic.

[Jose]

Watch this PCB in sprint Layus, conducted by IVCONIC, you can modify.
http://www.geotech1.com/forums/showt...433#post181433

[seadoggy]

Watch this PCB in sprint Layus, conducted by IVCONIC, you can modify.
http://www.geotech1.com/forums/showt...433#post181433

Ok thx jose alot.

[Jose]

Aquí encontré otra PCB en el foro, yo no hice este esquema, no se si es correcto. [ATTACH] 30709 [/ attach] [attach] 30710 [/ attach]

[Silver Dollar]

Chance Files;

[daverave]

GOLDSCAN IV PCB

is there a pcb availiable ready made for the goldscan IV ????

[greylourie]

No decent ones, Dave.

[daverave]

the goldscan IV looks very complicated but interesting but not sure if i would have the patience to produce a pcb using a cad programme...im very supprised no one has produced a quality pcb for this excellent gold scan IV !!!

[Orbit]

Is Eric Foster !

[greylourie]

Hello Dave,

If you look at the schematics, and take away all the circuitry bar one receive channel, it starts to become clearer. Once you get a bit of understanding, you realise that the ground balance function could be added to any of the common P.I circuits found on geotech.

The original was a non-motion machine. If you read the instructions, there were some interesting things you could do with the Hold/Auto switch, and the Reset button. The little circuit that these two controls were connected to can also be seen in some cscope p.i's. I think there is a similar circuit in the TDI, although without any user control/intervention. Sort of like a reset trigger for the sat cap.
Another interesting thing was the sel1/sel2 switch. Their function is also described in the manual. Reading threads here, you can find hints/tips/diagrams from Reg and Jose to make it more modern and have a simpler High/Low conductor select switch instead of the sel1/sel2 function.

It was also pretty powerful. And had a low repetition rate of 450 to 500 pps (adjustable for finding the quietest frequency). The sample widths and the delay between each of two samples in each channel were fixed. So were probably a best fit for a variety of metal targets, but not adjustable.

Would be a great project for learning basic ground balancing in P.I. Jose' has a wonderful video on youtube of his homebuilt clone. https://youtu.be/GEd9_PoW9bE

[daverave]

looking at the schematic i feel this design would be good if simplified down and remove the sel switch option...not sure if i will later at some stage try and make this...but for now got other projects to complete.

[greylourie]

I think having the High/Low select is one of its more positive points. If it is just ground balancing that interests you, then just use the sample timing logic. Then it becomes trivial to add to the project of your choice, like the hammerhead etc.

[Old cart]

Like the depth scale right on the detector shaft.

[greylourie]

Yes, its interesting. Also a battery meter there. The target strength indication is also found on modern P.I. I like the led array on the Garrett ATX P.I. I sometimes think, if Eric Foster was born in a different time and used micro controllers, maybe his Goldscan detectors might look quite similar in feature set to the Garrett. Its almost like a montage or a modern version or tribute in some small ways. Non-motion mode (especially the audio response) and the Retune button.

[Old cart]

Aquí encontré otra PCB en el foro, yo no hice este esquema, no se si es correcto. [ATTACH] 30709 [/ attach] [attach] 30710 [/ attach]

Has anyone built or investigated this PCB? Looks very well done based on superficial examination.

[greylourie]

Maybe Ivconic has the relevant schematic related to those two pdf's. I just wonder what the majority of members here want ? A Goldscan that coincidentally has ground balance, or a P.I with ground balance using the principles found in the Goldscan ?

Alexismex posted the first back engineered circuit. Very few errors or omissions. And those have been pointed out in posts on the forum. Offhand, there was the missing connections to GND on two J113 fets, allied with the two SAT caps. And with help from mschmahl, the presence of a 1nf cap in the feedback circuit that contains two diodes on IC3 was clarified. Theres a lot of useful posts scattered all over.

You could easily take the Hammerhead and add the logic/gating. Jose posted very good graphics showing the timings, simply scale to suit your PPS. And have ground balance. Add the circuits/switches Reg and Jose posted, and have selectable High/Low conductor signals. Now you have a very versatile detector.

It was pointed out to me that Orbit used part of the Surf P.I in his "GS6" creation. So you can see, to apply the GB principles can work and be applied.