RELIC HAWK

[robopatt]

Ok.
So mistake is not mine.
I see in front of my eyes exacly what you describe.Start oscillate when you switch DISC/ALLM switch.
Bun now I have manage to fix coils in such position that I have good performance in DISC.Sound at the begining of detection is good.But on closer targets or fast swing only constant sound.

[Max]

Yes, the circuit is ugly but that does not mean that it will not work.
Now I've got it. My test setup was faulty and I was acting like a dog chasing his tail.

One bad thing about spice is that it is hard to simulate circuits that generate ground because spice likes for ground to be the starting point, not an end. And, if it's ground then it's always going to be zero volts. (duh) You can't measure it, it's just THERE. Believe it. It's true.

Here I have hopefully corrected my error. It would take a lengthy explanation or else a picture. I'll draw a picture because I don't feel smart enough to make a lengthy explanation.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%

Here I have called battery(-) "ground" and ground is "0V". LTspice will not allow me to draw the circuit as it is would be in real-life, but I must transpose. In my picture we can see that if you have a 10V battery, the "0V" will be almost exactly half-way between B+ and B-. V+ and V- would get out of symmetry when the battery voltage is NOT 10V, so I don't understand why Minelab would do this. But, if it works, who cares?

Whew, I hate these crazy power supplies, but so what? Max, I thought your drawing was wrong but it was me that was wrong. Sorry.

Hi,
no problems... also cause drawing is not mine... I mean.... I added some value here and there but author is someone else.... that made reverse engineering on a real RH board.

All that voltages could be confusing... I know. The strategy itself is not bad at all... I see it good having a floating gnd with simm reference voltages for the trimpots etc. Looks really what I expect from that ML schematic... and the reference diode is another interesting thing: they wanna thermal stability from start, though not perfect stability thing seems well more advanced than having some old 7805 plus some voltage divider....I saw in other stuff.

And yes.... LTspice is useful but sometimes frustrating much....

Kind regards,
Max

[Max]

how many ????

Hi,
Max.
I am very glad that you are finaly here.
Have you checked this last schematic?Why there are 3 X 393?In yours there is only one 393?
Now I have some "idea" about that TR.Could it be this?

Hi,
I see.... it's Ivconic's reduced schematic I think....

Now back to the problem: 3 x lm393 or 1x lm393 ??? or both ?
Or... well... Ivconic's reduced schematic has 4x lm393.... really. (u3, u7, u11, u12)

You must consider also that there's an LM339 in original RH (we know that) and an LM339 contains 4xcomparators (an LM393 just 2) so it's like say that 4xlm393 are like 2xlm393 + 1xlm339.... do you understand what I mean ?

Kind regards,
Max

[robopatt]

Now I see.
Can you Please post the wirings for that previous PCB,so I can try it.

[Unregistered]

Robopatt why don't you list previous pages of this topic? Instead bugging and harrasing here?? None of your handmade will ever work, considering very none of your knowledge and understanding. Looking at your trivial question i am sure it will be better for you to buy new metal detector, instead trying to make one.
Are you tiktak, ultimate haze or not - does'nt matter. Tiktak, ultimate haze and you acting exactly the same; hundreds of trivial questions, zero understanding and zero knowledge.
With posts like yours this forum turned to very low level. Those few experts already left this forum, mostly cose of anoying persons like yourself. People can not appear here and deal with real things in fear that you and simillar to you will attack with bedlam of stupid questions and demands! Empty and trivial questions and stupid remarks. Sorry, life is rude.

[Unregistered]

It is absurd that anybody would think to make IB metal detector from scratch, untested schematic, and make it work without having oscilloscope and a good deal of experience.

Robo, puhleeze get a scope and give everybody a break.

[porkluvr]

Robopatt,
Your desire is admirable, but you are spinning your wheels by encountering trouble and trying to fix it by replacing parts instead of examining the situation.

Beg, borrow, or steal, but get an oscilloscope. You should try to isolate the problem instead of shotgunning everything. There are so very many little things that could be causing problems.

[ivconic]

Recently i got Minelab Musketeer Colt with 18cm TS800 DD coil.
I had same model few years ago. This time i had unbeleivelable luck; guy from USA advertised it on ebay as brand new, never used. Actually never unpacked from original package!!! Device stayed in shop window as exhibit all those years , unpacked !!! So guy recently decided to move shop and therefore was pushed to sell all the exhibits from there. Can you imagine my thrill! Colt...old model.."cult" model in original shape, brand new, never used, shiny and polished!!! Wow!
A good friend from Slovenia bought it for me and it took almost 3 months, with much help from another good friend to import it here to my place.
Finally all the anticipation repayed. It is here.
I dont have word to explain joy working again with it on the field. Yes...we have now Advantage - exactly the same machine with some presets more on front panel...but, Colt is Colt. With that retro look and that retro feeling...nothing can substitute it ever!
Also i have 36cm,39cm and 45cm Excelerator coils for it.
Spring ... time for prospecting, so i am planning to spend whole season with it outdoor. Later...maybe in October i am planning to open it and finally redraw whole schematic. Also to decipher all the doubts here about it. That will give us (once for all) most proper and most accurate schematic for this subject (same thing as Relic Hawk, just without SML modes)....
Until than...

[nakky]

Ivconic,I can't wait. Grt Nakky.

[ivconic]

What really makes this machine very special (Colt,XS and Advantage) is its audio - audio response. On skim look audio is very poor, single freq. and very simple. Ha,ha,ha...; this is only on skim look. After spending some time with it, operator will realize fantastic audio which carrys much informations about target. That is what i always wanted to gain with my favourite project - TGSL.
One more thing; coil sizes. I tested all mentioned coils with it. Larger coils do cover larger areas on soil and of course do go a bit deeper. But smallest 18cm TS800 coil is just fantastic to suit most of prospecting demands. It is going very deep also. It is real challenge to make such small coil and maintain good performances and excellent depths.
How they done it?
Also this will put more light on one, also very interesting question; depths and coil size relations at IB's...

[Ultimate_Haze]

Congratulations,
That's realy good news.
I havent chance to test XS or Colt but seen RH in action and its real trill.
Personaly I doubt that even latest MLs will go deeper on such hard soil.
About the audio all true.Man have to see for himself.Hard to explain but great target indication with some sort of bang when good.Can be frustraited buy some large irons bot most detectors cant even see such deep targets.
Wish you luck on your happy vacation in forests.

[Ultimate_Haze]

Porkluvr,
Is Tektronix 2232 100 MHz DIGITAL STORAGE OSCILLOSCOPE good enough?
I will have it in a fiew days.So everything will be diferent.
Also get two brand new probes.
Now that its old but it were greate deal,so I will have to live with this.

[Max]

Recently i got Minelab Musketeer Colt with 18cm TS800 DD coil.
I had same model few years ago. This time i had unbeleivelable luck; guy from USA advertised it on ebay as brand new, never used. Actually never unpacked from original package!!! Device stayed in shop window as exhibit all those years , unpacked !!! So guy recently decided to move shop and therefore was pushed to sell all the exhibits from there. Can you imagine my thrill! Colt...old model.."cult" model in original shape, brand new, never used, shiny and polished!!! Wow!
A good friend from Slovenia bought it for me and it took almost 3 months, with much help from another good friend to import it here to my place.
Finally all the anticipation repayed. It is here.
I dont have word to explain joy working again with it on the field. Yes...we have now Advantage - exactly the same machine with some presets more on front panel...but, Colt is Colt. With that retro look and that retro feeling...nothing can substitute it ever!
Also i have 36cm,39cm and 45cm Excelerator coils for it.
Spring ... time for prospecting, so i am planning to spend whole season with it outdoor. Later...maybe in October i am planning to open it and finally redraw whole schematic. Also to decipher all the doubts here about it. That will give us (once for all) most proper and most accurate schematic for this subject (same thing as Relic Hawk, just without SML modes)....
Until than...

Hi,
read it just now! Wow, that's exciting info!
Congratulations!

I have also in mind of clear all dubts about it... but still too many issues here to take a serious plan on RH board and circuit!

I think will be a nice thread in next autumn/winter.... till then... hope you'll find alot with that thing... Have a nice hunt season !

Kind regards,
Max

[erolunall]

Hello

I asked my friend Asenkron to Draw new PCB for RH at http://www.geotech1.com/forums/showt...=14025&page=27

He is ready to draw but some questions.

Shematic is True? İt is simülated on LTspace
Power suply lines İs not Clear
There are a part which both side 2X2600uF Codansatörs , writing power. What is this part? all Op-amp names list and input voltages for Op-Amp. Last question There are some + - and +2.5 -2.5
is this same for all schematic

Asenkron said He needs this information to draw a good PCB
if Someone explane this questions. He will draw a new PCB for Relik Hawk in two day. He is waiting İnformations.

Best Wishes
Erol

[Fred]

Hi Erol,

I don´t understand all your questions, bu i will answer what i can:
-Max version of schematic is the most accurate,it works but with some minor problems, maybe due to the bad PCB layout.
-it is not 2600uF it is 26 pieces of 100nF capacitors, for decoupling below u1 to u13.It is not a part, just to show decoupling must be done below each IC, with 2 caps (13ic´s X 2caps=26).
- yes +/- 2v5 is common for the whole circuit.

I think has been partly simulated on ltspice.
Regards,
Fred.