GC-1023

[Unregistered]

Any one got a schematic for the Gold Century GC-1023. It has been sold worldwide as:

Gold Century Metal Detector GC1023
MD-1023
Famous Trails Discovery Metal Detector
Fortune Finder 1023 Metal Detector
Treasure Cove Metal Detector TC-1023
Gold Snoop (Australia)
Gold Snoop Pro (Australia)
Lafayette GC-1023 (Italy)
Black Knight Pro (Germany)
Magpie II (GC-1023) (Germany)

Made in China.

[RufusGartz]

GC-1023 pcb

I have pictures of both sides of the pcb. Component side is numbered 21SJ7.820.085 & dated 2005.7.27

Carl, as a new member, when am I able to attach the pictures as my posting rules are "You may not post attachments" & what is the size limit.

Rufus

[RufusGartz]

pcb pictures

2 pics:

[Unregistered]

gc-1023

Hi everyone, looking for the same circuit. My metal detector is the md-1023, same as the pictures above. Looking for circuit to do some modifications to it. Highly appreciate some info.
cheers, George..HH

[amtech2005]

GC-1023

NO SCHEMATIC YET !!!! BUT SINCE IT IS MADE IN CHINA , IT IS COPIED FROM SOMEONE ELSE !!!! WE KNOW ITS 5.0 to 6.5 KHZ. IT WILL DETECT A QUARTER AT 8 INCHES IN ALL METAL MODE. IC CHIP U-1 , U-2 AND U-6 ARE NOT VISIBLE . THESE MAY HELP ,IF YOU CAN SHOW US A BETTER PICTURE. U-3,U-4,U-5 ARE CLEAR. I ALSO POSTED THE 12 INCH COIL YOU CAN GET FOR IT TOO. WE JUST NEED A BETTER PHOTO . THEN WE MIGHT BE ABLE TO MODIFY THE CIRCUIT. TIME TO GET OUT YOUR OSCILLOSCOPE TOO . A GOOD OSCILLOSCOPE CAN ALWAYS ANSWER MANY QUESTIONS !!!IT MIGHT BE A COPY OF A FISHER??? I KNOW FOR A FACT THAT THE CHINESE ARE MANUFACTURING A COPY OF WHITES CLASSIC 3 AND ALSO 6000 PRO AND SHIPPING THEM AROUND THE WORLD. "REBUILDING OLD TECHNOLOGY FOR A BUCK" AND RE-SELLING FOR $$$$$$$$. HOPE THIS HELPED A LITTLE ...................EUGENE

[RufusGartz]

Operates at 6.6KHz according manufacturers website..

Parts Listing for GC-1023/MD-1023:

IC:
U1 = TL064CN
U2 = LM393N
U3 = CD4053BE
U4 = TL064CN
U5 = LM393N
U6 = TL064CN
U7 = TL431AG

Transistors:
Q1 = S9013
Q2 = S9012
Q3 = S9014
Q4 = S9013
Q5 = S9013
Q6 = S9013
Q7 = S9013
Q8 = S9013
Q9 = S9013
Q10 = S9012
Q11 = S9013
Q12 = S9013
Q13 = S9013
Q14 = S9013
Q15 = S9012

... Rufus

[Unregistered]

Yes, they are the right components as listed above. I am trying to locate a similar circuit on this design but with no luck. Could be similar to bounty hunter tracker iv, but cannot locate circuit. One other thing that has crossed my mind is i think the Tx oscillator is built in the concentric coil. I may be wrong. Does anyone know the tx/rx colored wires in jumper J1 on the circuit board above (blue, green, yellow, orange)? Wanting to know the pin configurations that connect to the coil. Any help Please.....
cheers George...

[bernte_one]

have this model too

if anybody want i can post some high res macro photos
maybe for re engineering
the performance is not bad but sometimes critical at wet grass
good working disc

get it in mind when thinking about to use the coil from it for my tgsl
maybe it works would be the cheapest coil (bougt the whole unit for 38 Euro new)

[sido]

I am surprised this model detector has not been re-engineered out of all detector circuits published on this forum and others that i have seen, It is Chinese, it has found me many relics and coins, i have modified it for extra sensitivity (front end mod for extra sensitivity.....0.3 gram gold nugget at 1.5 inch)
The excellent aspect of the detector is its QUITE... (no noise, no threshold) and great depth (for me 28cm for gold ring, with discrimination). Have had no time to re-trace circuit, but i believe it has potential....why.....because it works silently in Australia's high mineralization soil's, gold soil's, which are difficult, which is a good chance that it will work any other soil condition's around the world. Has a decent discrimination as a bonus. Works under powerlines 240 volts Hz (not sure about 110 volts) and works under factories with machinery nearby.
The only drawback is the coil, it is a 8 inch concentric with the transmit coil being only 4 inch in diameter, thats why it has good selectivity and depth. If people are interested we can work out a better coil. I am designing a few coils at the moment exspecially for small gold.

Anyone interseted in mods on the front end for extra sensitivity, let me know, i will post mods.

This is a good detector but needs more looking at, for even better operation.

If you want extra sensitivity, change op-amps as different op-amps have different specs.....and a couple of resistor's.

Bernte one, pictures would be great....thanks

Sido HH

[bernte_one]

hello sido

i dig this old post out cause i think same like you.

would be great if you can post the mod here why not im interested in them

this night i will collect my srewdrivers and take some photos of this machine

[amtech2005]

Thank-You for keeping this subject going Bernte One . I have not lost interest in the GC-1023 specifications . Did yours come with the big coil or little coil ?

Best Regards.............Eugene

[bernte_one]

Hello,

i´ve the one with the standard coil. Pics of pcb are made. I will post one here the others i send to a file hoster so that everybody can download them in good quality. All components in smd- good made seems it was a little chinese with small fingers.

Inside the box are other pcb too. Some at the knobs and one on the coil connector seems they are made for easier wiring and saving space all is very flat mounted. I will post them later.

If anyone starts next days to redesign pcb- its not necessary to made it in smd too i think it were user friendlier and easier to rebuild it with standard size components.

The parts that are glued in hot glue are not so easy to analize but most tracks are visible- if not i can use a strong light from the back (laser or led) to make them clearer visible.

[6666]

Its funny this detector has been around for years in one form or another yet I have never seen a cct for it

it must be highly secret

Sido please tell us about your mods

[sido]

Hi again all, bit under the hammer at the moment with work commitments.
6666, will catch up with you on OZ forum soon.

First of all, please note there seems to be varying degree in success with this detector for different people. What i mean is when they came out of the Chinese factory, as would be expected, some work good, some do not work as good and some work great like mine, but in saying that, if this circuit diagram can be traced then its a good starting point to getting most of the not so good units working great or total new designed board, does not have to be SMD. It is a good design, whether being a copy or a genuine Chinese design. Some say its a copy of BH Tracker IV, but i have compared and do not match.

What i believe is that the circuit board and components will be correct for all units produced in production and sold worldwide, but whats caused failure in some is the IC's, COIL and DRY JOINTS. Why because the coils are manufactured not to specification, possibly not tuned correctly or nulled correctly. The IC's vary in performance by different manufacturers and soldering we all know is no good.

If someone has a faulty/damaged 8 inch coil for this unit please post a picture of the inside and your inductance measurements so we can compare and also improve coil design.

My measured inductance is TX 1.98mh and RX 8.88mh, could be wrong, checked with cheap meter. Will check again soon.

I believe the coil is concentric in design having TX inner, bucking coil outer and RX outer, sourced this info from some other site.

Tried to measure quickly Frequency, had no luck, Will try with another meter soon with good coupling meter leads. People say its 6.7 Khz, would be nice if it can be modded to say 12-15khz with new coil design in future. Has potential for improvements.

Bernte-one your right no need for SMD design.

Ok, as for mods, I will post them this weekend, i have to refresh my memory what i did to the unit, meaning component value changes, will have to open unit up.
Will also try to trace part of circuit, never tried this before, just need the time. This will be slow going for me.

As for performance, set sensitivity full, i can use this unit 30 meters from electrified Railway lines while train passing with only a bit a chatter breaking through the silent threshold, amazing....High mineralized soils in the Victorian Golden Triangle, one of the worst in the world, still runs silent....i am very impressed, i do not think there is any other detector out there capable of that. The only place i have not used this unit is under or near high voltage power lines...the ones that carry 50,000 volts i think.

PS: How do you post a picture, tried to upload from my PC, but could not get pass MY Pictures icon to select a picture.

Cheer's Sido

[lunamay]

hi to all

i have sae detector somewhere in a basement...i was wondering..maybe someone could tell me what is wrong with it..
once i noticed that it started to be very noisy(on disc and pinpoint also) now i cant find any problems on pcb so maybe coil? i would be wery gratefull for any opinions..maybe someone has same probelm..


best regards