RELIC HAWK

[tiktak]

Hi

Hi,
Ivconic.
Can you please tell me what is this part in pic.1 from post #89 of this thread in the top left corner of the PCB?Is this the 1mH or?It looks prety strange?
Also can you now post some better pictures of RH PCB so we can all work together.
Are there any components of the bottom side?
When I look those pictures that I have from you I can see some diferances with the schematic here.So maybe you are right again.
But Max have achived so good results.

[Eugene52]

RELIC HAWK

Hi guys,
I made lot of experiments with that pcb/schematic and I have to say that it worked as expected apart the silly far-iron detection, probably due to my wrong homemade coil... really probable it's my fault there at coil.

In my cloned RH I put 100n capacitors for decoupling under the pcb, using a wire (open loop) to make an additional ground track, kinda of flying mounting like in rf stuff.

I didn't use any container so have no extra shield in most of testing and see device run stable and performative on small stuff, though it shine on medium and big targets, much more powerful of average mds.

What if I run it using full shield ? I don't know... maybe works even better than I saw.

At now I can't test... I can't read here or post like before, but when possible I'll look at here for news.

I think the schematic is about correct... maybe one or a couple of things with mismatched values but not major issues.

The interesting fact is that I can disc iron at few cms and still detect very deep e.g. 1eur coin, silver coins etc. so can't be totally wrong.

Also, all-metal works too and is deep, and geb works very well also, so the big issues to me is always at coil... not at schematic or pcb we use.

About ne5534 , I'm not sure it was there in original RH but think so cause of the wiring in schematic... otherwise what else ? LF356 ?

Anyway, still my troubles are unsolved so I will be out of forums for a while.
Hope you'll got good ideas about further refining.

Kind regards,
Max

Hello Max , I believe you had the Relic Hawk circuit board 95 to 100% correct !!! If there was an error it was something to do with transistor "types" and or the part numbers in regards to the TX oscillator section . I believe you just made a very minute 1% error with the search coil . MAX , I classify you here on this Geotech Forum as an electronics engineer / Design Engineer / Electronics Technician , all 3 , so you are in an elite Group with Geo, Ivconic , Fred , Carl , KingJL , KT315 , Aft72005 , and and maybe a dozen other Top notch Techs here , "Please anyone do not be upset if I do not mention your name here , too many to name to type "!!!!! Again , hundreds of top-notch techs are on this Geotech Forum from around the world !!!!!!!. Max , I have no-doubt in my mind that the Relic Hawk will be completed with your help . Me , I am just a repair Tech that can repair anything electronic , that is put in front of me , how I do it amazes even me !!!!! As for design work , I am not quite ready , but learning here everyday . As for Metal detecting in the field , I have a lot of experience since the mid 1970's ,even a lot of deep digging and in the worst possible "hard pan" dirt and clay ........This Geotech Forum is all about Team work and "every member" here I respect and appreciate. I hope this Geotech Forum is here for years to come . Max , as soon as you complete and conquer your personal issue , we all want you back here to complete and conquer the Relic Hawk Challenge , and all other Geotech Forum Electronic Projects / Headaches/Mysteries !!!!......Regards.....Eugene 52/ Formerly amtech2005 / Stalni-Clan member of Ivconics Hobi-Detektori site

[Max]

my impressions on actual RH

Hi guys,
I made lot of experiments with that pcb/schematic and I have to say that it worked as expected apart the silly far-iron detection, probably due to my wrong homemade coil... really probable it's my fault there at coil.

In my cloned RH I put 100n capacitors for decoupling under the pcb, using a wire (open loop) to make an additional ground track, kinda of flying mounting like in rf stuff.

I didn't use any container so have no extra shield in most of testing and see device run stable and performative on small stuff, though it shine on medium and big targets, much more powerful of average mds.

What if I run it using full shield ? I don't know... maybe works even better than I saw.

At now I can't test... I can't read here or post like before, but when possible I'll look at here for news.

I think the schematic is about correct... maybe one or a couple of things with mismatched values but not major issues.

The interesting fact is that I can disc iron at few cms and still detect very deep e.g. 1eur coin, silver coins etc. so can't be totally wrong.

Also, all-metal works too and is deep, and geb works very well also, so the big issues to me is always at coil... not at schematic or pcb we use.

About ne5534 , I'm not sure it was there in original RH but think so cause of the wiring in schematic... otherwise what else ? LF356 ?

Anyway, still my troubles are unsolved so I will be out of forums for a while.
Hope you'll got good ideas about further refining.

Kind regards,
Max

[ivconic]

Ok Ivconic,
No problem, i understand better you point now.You have much more experience with detectors than i have , so if you say something is wrong i think you have your reasons.But what i cant understand is why you give up so quickly, i think the RH was a good detector and clonig it could be interesting.
I don´t think caps are a problem, i have often seen (digital) circuits with caps below the IC´s, to have short leads.100nf caps are small and fit well there, with GP they are easy to connect.(Personally i prefer ugly caps making a good job than the contrary)
Now the design may be bad, i respect any opinion, but then it means it can be improved.
Now if you think there are errors on schematic you certainly have your reasons too,but i dont´t know where.If i remember well one that Max have found was a tricky one,swapped channels at 4066 IC.
Finally, about political stuff, it was not personal at all, ( i am apolitical too,) but i was thinking it was maybe about origin of schematic .(To be honest i don´t even know what is origin o schematic, and i don´t care, but you comment made me think it was this.)
I will finish my RH anyway, to see how it works.Aparently they all work decently but with instability, so this have to come from somewhere.My PCB is the only one with GP built so far , so it will be interesting to see how it works.
Best regards,
Fred.

That's what i am explained here already - it is not so quick. I spent already plenty of time dealing with several versions of RH. None of those worked well so far. I have habit not to post news during working and experimenting, so i didnt talked much about it. Now when almost all checked many times i decided to give up. RH is splendid machine, i had it and worked with it. But it is tricky to be made cose a pretty delicate design. Some stages has huge amplification and some very low. Man has to pay enormous effort to satisfy all the aspects there. Original pcb is drawn pretty carefully. Hums and intermodulations are reduced to minimum, yet without original Al enclosure it also produces bedlam of noise! I saw that recently.
Front end has medium to low amplification, yet further stages do have hi amplification. This is done in manner to reduce external hums to be catched and amplificated along with usefull signal. Than in further stages usefull signal is amplificated madly. So hums we are having at our handmades are more like "internal" than external. All those due inproper pcb composition and chossen components mostly....
RH is prety delicate design but at the same time not so valueable to "die" over it. There are more modern and easier solutions now, we can play with.
So that is my standing point. Of course it is pretty subjective - doesnt mean i am right and you are wrong. I will give up and pay attention to other things, but i will carefully read all what happening here in future.
Best regards Fred!

[Fred]

Ok Ivconic,
No problem, i understand better you point now.You have much more experience with detectors than i have , so if you say something is wrong i think you have your reasons.But what i cant understand is why you give up so quickly, i think the RH was a good detector and clonig it could be interesting.
I don´t think caps are a problem, i have often seen (digital) circuits with caps below the IC´s, to have short leads.100nf caps are small and fit well there, with GP they are easy to connect.(Personally i prefer ugly caps making a good job than the contrary)
Now the design may be bad, i respect any opinion, but then it means it can be improved.
Now if you think there are errors on schematic you certainly have your reasons too,but i dont´t know where.If i remember well one that Max have found was a tricky one,swapped channels at 4066 IC.
Finally, about political stuff, it was not personal at all, ( i am apolitical too,) but i was thinking it was maybe about origin of schematic .(To be honest i don´t even know what is origin o schematic, and i don´t care, but you comment made me think it was this.)
I will finish my RH anyway, to see how it works.Aparently they all work decently but with instability, so this have to come from somewhere.My PCB is the only one with GP built so far , so it will be interesting to see how it works.
Best regards,
Fred.

[ivconic]

I dont understand:
-at first you got 45cm , now it´s no good
-PCb have Ground plane, but you didn´t make it, now you sayt it´s bad design
-we checked errors, and corrected the ones we found (specially Max), now it´s full of them...

If you don´t like the diagram for political reasons, fine, but if it´s tecnhical i´m sure that can easily be improved.

Fred...!?!?!? What political reasons??? I am apolitical totally, i dont even know you and your origin. Or maybe you think i reffered to Minelab....Australia...it is on the top of my favorite list! What political reasons ...dear Fred!?!?
You did excellent pcb draw according to schematic, but schematic lack...now i am sure. It is not your fault, you used incomplete schematic...that is all. I am not acusing you or anybody else here for nothing.
Yes i had 45cm and more on 1e coin but with huge instabillity, uselles on soil. Now i have doubts that it was not real detection at all but some wild reaction in the air...?! Not sure at all?
Also i have in mind original RH pcb and serie of measurements and tests me and my friend done recently - totally oposite behavior than this one.
This one is not promissing at all.
Than ..capacitors..omitted from pcb, not good - bad very bad. It is not "work" to do like that - to add capacitors after..very bad and sloppy job.
So...we need another, new pcb with caps included.
But what if we draw another again according to inaccurate schematic?
I spent some time on "Coinseeker"...now on this...no results.
So...that was my point....not some "political" (God oh no!) reasons or whatever else...!!?!?


Fred best regards, man! Take it easy!

[Fred]

No,no...this is totally wrong,mismatched.
I am not gonna waste my time and nervs on this trash. Schematic is full of mistakes so logically pcb too. Also pcb is not good drawn at all.
5kg hammer will do the job in a minute!

I dont understand:
-at first you got 45cm , now it´s no good
-PCb have Ground plane, but you didn´t make it, now you sayt it´s bad design
-we checked errors, and corrected the ones we found (specially Max), now it´s full of them...

If you don´t like the diagram for political reasons, fine, but if it´s tecnhical i´m sure that can easily be improved.

[ivconic]

No,no...this is totally wrong,mismatched.
I am not gonna waste my time and nervs on this trash. Schematic is full of mistakes so logically pcb too. Also pcb is not good drawn at all.
5kg hammer will do the job in a minute!
This is far away from any descent working and behaving.
I already lost so many time and nervs on pretty nonsenced and foolish drawn bulgarian "Coinseeker"...now i am wasting my time on this..!?
No more!
There are other nice and workable projects i could spend my time smarter.
I am OFF this subject from now on.

[Max]

Max ,

All of us here are waiting for your return , The sooner the better !!! Kind Regards and Best Wishes from all of us !!!!!!!! ..........Eugene

Thank you, I really appreciate, it's really troublesome and sad time for me at now.

Kind regards,
Max

[Max]

I added 100nF caps on all ic's supply pins. And i lost all !!!???
Now, sound is very weak, bairly audible and detection is none....1e coin bairly at 5cm in the air!?!?!?
It is more "stabille" now....although there are some ocassionall background chatters in audio.
So... new moment now..!? Hmmm...
In previous posts i beleived that we have final and error free schematic and pcb, now....i am not so sure any more..
Cose...i do have original coil and coil is not in question anymore.
Something is mistaken...

Hi,
I connected caps under the PCB using kind of flying mounting for them. I used an open loop (made of solid, rigid wire) as gnd track.

Be sure you didn't made a big ground loop when doing this, that could explain bad performance.

I'm really sorry I cannot follow this thread and all forums at that time, but I will try to look at here when possible.

Kind regards,
Max

[ivconic]

I added 100nF caps on all ic's supply pins. And i lost all !!!???
Now, sound is very weak, bairly audible and detection is none....1e coin bairly at 5cm in the air!?!?!?
It is more "stabille" now....although there are some ocassionall background chatters in audio.
So... new moment now..!? Hmmm...
In previous posts i beleived that we have final and error free schematic and pcb, now....i am not so sure any more..
Cose...i do have original coil and coil is not in question anymore.
Something is mistaken...

[ivconic]

Hi,
I'm sorry I cannot read here much and post at now about, have really huge troubles these days and really no time to mess with MDs and hobbies.

I used all that caps under the RH's PCB, that's essential to keep it quiet.

I also removed a very bad ground loop...caused lot of noise in signal path.

My disc problem is with iron at far distance, maybe depends on coil I made.

I don't know at now when I will be back here to discuss details, hope will be soon.

Kind regards,
Max

Ok Max, take your time. This is only hobby, can wait. Wish you to overcome your problems as soon as possible and to come back here.
Best regards!

[ivconic]

Hi Ivconic,
That´s good news about the disc and speaker influence.We must try metallic enclosure too.
If you removed GP i guess you had to make all new traces again to connect ground to components...but that leads to loops somewhere.
About the caps, i could not find a way to include them in PCB yet keeping leads short, so i decided that hey will be soldered on the other side, below ic´s.better performances this way, even if it will not look so nice.
About speaker influence over stability, one could just connect a separate power supply foa audio amp and see how it improves.

I still have to build the coil, so any information you have that could help building it right one will be appreciated.

Best regards,
Fred.

About coil...i already gave datas of original coil.
You can try to make your own respecting inductances and resistances.
Next time i switch on RH i will measure residual voltage on RX coil and post here.

[ivconic]

Eugene that is the one. Yet i can not see audio wirements proprerly....all the components seems same asa on RH..
Anyway thank you!

[Eugene52]

Hi,
I'm sorry I cannot read here much and post at now about, have really huge troubles these days and really no time to mess with MDs and hobbies.

I used all that caps under the RH's PCB, that's essential to keep it quiet.

I also removed a very bad ground loop...caused lot of noise in signal path.

My disc problem is with iron at far distance, maybe depends on coil I made.

I don't know at now when I will be back here to discuss details, hope will be soon.

Kind regards,
Max

Max ,

All of us here are waiting for your return , The sooner the better !!! Kind Regards and Best Wishes from all of us !!!!!!!! ..........Eugene