GOLDSCAN 5 SCHEMATIC QUESTION

[daverave]

Dave, without a complete and vetted schematic you have a long hard road ahead of you. I've not seen a complete GS5 schematic so can't help you there, maybe no one else can, either. FWIW, the TDI is the same design as the GS5 but with (maybe) a different audio back-end, not sure about that. Someone may have traced out a TDI schematic since they are more prevalent, though I don't recall ever seeing one posted.

If the GS5 is your goal, I suggest building it incrementally and learning what everything does as you go. Since I know the TDI circuit well, I can help out with explanations & suggestions if you have specific questions.

Hi Carl...I appreciate your suggestions and maybe i will try and build a gs 5 from site diagram and although i like the gs 5 audio i will have to settle for a normal vco type audio...i do hope that it may have some id against iron as where i live on the beaches iron is a big problem and hard work keep digging it up !!! the other thing i want is the frequency control so i can reject some noise...the projects that ive made in the past have no frequency shift and i have to put up with interference from electronic road crossings and amusement arcades.

[Carl-NC]

Dave, without a complete and vetted schematic you have a long hard road ahead of you. I've not seen a complete GS5 schematic so can't help you there, maybe no one else can, either. FWIW, the TDI is the same design as the GS5 but with (maybe) a different audio back-end, not sure about that. Someone may have traced out a TDI schematic since they are more prevalent, though I don't recall ever seeing one posted.

If the GS5 is your goal, I suggest building it incrementally and learning what everything does as you go. Since I know the TDI circuit well, I can help out with explanations & suggestions if you have specific questions.

[daverave]

hi Dave

maybe then our hard way to buy nonworking GS, atomize it on atoms and learn.
you get working GS, all info, board and sell it, money be back. mine part of the job - desolder pcb, CADing, order pcbs in cnina.

Hi kt...i cannot afford to buy a non working gs 5...i have a lot of debt so i cannot buy much these days...im not into selling my projects and mentally i could not make things to make money...i can only at present just about cope with trying to make something for myself and wife to use...i just want a detector like a gs 5 that i can feel confident that i can find something nice...i get my hopes up but nothing ever happens to me...but thats life i guess.

[kt315]

hi Dave

maybe then our hard way to buy nonworking GS, atomize it on atoms and learn.
you get working GS, all info, board and sell it, money be back. mine part of the job - desolder pcb, CADing, order pcbs in cnina.

[daverave]

with your english.... that certainly perfect... i would have to cling to one's throat deadly...
more often remind this man... a life is so tiny that on tomorrow we will ask the schematics from his wife LOL!!!!

http://www.geotech1.com/forums/member.php?237-Ferric-Toes

act my friend ))

Hi kt..thanks for your reply....to be honest im too fed up now and down in myself to bother anymore..if people dont want to help me then so be it...maybe i ask too much of people.

[kt315]

with your english.... that certainly perfect... i would have to cling to one's throat deadly...
more often remind this man... a life is so tiny that on tomorrow we will ask the schematics from his wife LOL!!!!

http://www.geotech1.com/forums/member.php?237-Ferric-Toes

act my friend ))

[daverave]

here. he has.
http://www.findmall.com/read.php?34,...20#msg-2113320

Hi kt 315....thanks for the link...it seems not many people on this site want to share any info on the gs 5...i wonder why a closed shop on this subject ????

[kt315]

here. he has.

http://www.findmall.com/read.php?34,1935936,2113320#msg-2113320

[daverave]

i guess there must be other people on this site who have made a gs 5 and i would appreciate any advice in trying to build one without circuit errors contained in the posted schematic shown on this site.

[daverave]

Hi eclipse...i would guess the all metal sample would be adjusted as normal to give approx between 10 - 15 uS delay but the grey area for me will be the ground balance sample position which i know absolutely nothing about so maybe trail and error to get this correct

[eclipse]

I'm referring to the trimpots in the Timing section (see GS5 near the 453 - if those adjust the pulse timings in wide range (for ex: more than +-20%)
you have no way to find out the original timings.

[daverave]

I guess you should start and build the PSU & Timing circuit first.
PSU - just use minipulse one, you need +12V (GND), +5V, -5V.
I see lots of trimmers in the Timing circuit and no way of knowing the original settings, so this maybe a bust right from the start.

Hi eclipse...comparing the trimmers between gs 4 & gs 5 it looks like most of the trimmers in the ground balance section are adjusted to give a 0v output from each op amp.

[daverave]

ive decided to try and make the gs 5 from the schematic....the first part of the schematic seems straight forward but i found a couple of errors...also the coil voltage in the diagram is regulated at -10v which i guess should be -12v...i want the circuits to fit into a 50mm tube so i have to use a verro type pcb's...i like also the gs 5 cause the tx frequency runs at around 3 khz which i read gives a better signal to noise ratio...i hope that i can build this cause it will be a great help to me on the beach.

[eclipse]

I guess you should start and build the PSU & Timing circuit first.
PSU - just use minipulse one, you need +12V (GND), +5V, -5V.
I see lots of trimmers in the Timing circuit and no way of knowing the original settings, so this maybe a bust right from the start.

[daverave]

If I were you would start from building the GS4. If you take a closer look at the GS6 (yes not a mistake, people called this mod GS6) link there I posted
you will see that the modified version is incredibly close to GS5 schematic.

From what's available as info for GS6 - the PSU, TX, Preamp, Gates & Integrators - it's all there and should be close to working (make a dual stage preamp).

All this can be taken directly to your GS5 build. So I'm suggesting you follow the GS4/6 to build the GS5.

After the signal integration (point A & point B on the Lugatek turkish PDF) is what's new in GS5. This part you may fail if there's an error. If you successfully build this section you're winner.

Yes audio sections can be borrowed. Must be absolute value VCO. There are few available here on the forum.

hi eclipse...i would have liked the two tone audio but maybe just have to settle for a single vco....i may try and build in a round 50mm tube as i did in my other project...i like the gs design as it has a frequency control which is a must on our local beach as much noise from road crossing electronics and amusement arcades...ive never had a detector with a frequency control....not sure about the ground cancell on the gs as ive never really understood how it works...and how it can reject iron as on the gs 5..if i can make a working detector on a verro type board in separate stages then i will be happy with something i can feel confident with on the beach.