Need help with Arado 120b pcb picture

[ivconic]

"..Ivconic, does your camera have a flash?..."


Yes....and no!? If i use flash than it switches off fast, drains battery fast. With new batteries sometimes i manage to get clear photo and sometimes i get only white and nothing else. Old camera, 2.1 MPX.... must buy better one.
I experimented with option trough it's menus and can't manage, no way!


Making copy of Arrado would not be a problem. Only component that bugs me is that variable capacitor for tuning. Hard to find exact. Original is HUGE. I was thinking how to replace it with some "active" electronic.
Arrado is not so good in locating single coin, but it is good enough for larger items. I have old version from 198x ! But also there is new version on market. Nothing changed inside, only new enclosure design and new coil..
Regards!

[technos]

"
Making copy of Arrado would not be a problem. Only component that bugs me is that variable capacitor for tuning. Hard to find exact. Original is HUGE. I was thinking how to replace it with some "active" electronic.

Oh really? - the 150pf variable cap was used for tuning?? Yikes, I thought that's what the 100K pot was for!? - and the 150 pf was a small trimmer used to "null" coil. But that does explain how the circuit is simpler. But yes, having that big of a variable cap around is hard. I did read in some places about a mod to put a 10:1 reduction drive (more cost for that) to make tuning easier. Some have it built in - does this one?

Big variables are hard to find, expensive, and don't fit in a case well. I would like to replace it too. The problem - Q of varactor diode = 200. Q of smaller tuner capacitor (like what's in a AM transistor radio) = 500. Q of big tuning capacitor (what must be there) = 2000 - imo changing that would be an issue the way it is hooked on the coil. I may have to use one just to get this circuit built. The other option is to use a coil design like the early whites that had a null circuit in the coil itself. But that's hard to wind.

The whole thing that attracted me to this circuit is it's simplicity.

BTW, the transistor 4058, is that a 2N4058?

[ivconic]

"..Some have it built in - does this one?..."

Not this one i have.
...
Yes it is 2N4058.

[Mikes]

Greetings,Ivconic !
Has decided to write to you about results of work F1266!!!
Now works ÎÊ!
It is desirable!!!!!!! In parallel R425 to put the resistor 100êÎì and the diode (as in F1266) and all will work normally. Instead of resistors R324, R313 – 22 kOm – to put till 27-33 kOm. Now you PCB F1265 at me works excellently! Two payments of yours PCB have made and both work normally and even is excellent!!!
I, regret, but my comments on Fisher 1266 have entailed not good consequences – destruction of my site – http:/mikes.front.ru.
Yours faithfully, Michael (MikeS).

[ivconic]

Greetings,Ivconic !
Has decided to write to you about results of work F1266!!!
Now works ÎÊ!
It is desirable!!!!!!! In parallel R425 to put the resistor 100êÎì and the diode (as in F1266) and all will work normally. Instead of resistors R324, R313 – 22 kOm – to put till 27-33 kOm. Now you PCB F1265 at me works excellently! Two payments of yours PCB have made and both work normally and even is excellent!!!
I, regret, but my comments on Fisher 1266 have entailed not good consequences – destruction of my site – http:/mikes.front.ru.
Yours faithfully, Michael (MikeS).

Glad to hear that!
Can we continue here:
http://www.geotech1.com/forums/showt...highlight=1265

[Sean_Goddard]

If you have a faulty Arado, it is ALWAYS the coils. They sucked!

try tuning to mid range then slide a copper washer (around 3/4 dia.) around the TOP of the SH ...SLOWLY at one point the detector will tune. if not try a STEEL one and do the same. the heads go out of balance due to the foam in them, it shrinks with age and the coils move.

Should be easy to make a new on, if you do I'll buy one off you I have a duff Arado and don't have time to fix it.

Depth is GOOD on low mineralisation soil, but rubbish on anything else. Not as good as say a TGS though.

[Sean_Goddard]

hey Ivconic, I like your new avatar ;-))

My friend calls me Beaker

[ivconic]

hey Ivconic, I like your new avatar ;-))

My friend calls me Beaker

I like it too!
Right now, in this time of the year, it perfectly suits my personallity!
Mee meeep!

[ivconic]

"....the heads go out of balance due to the foam in them, it shrinks with age and the coils move...."

I had coil fixed in joint filler and than in foam. Looks like it is impossible to move, yet it moved in time!? So you are right about that.
I tried to fix it up in the past and destroyed it completelly!
It would not be a problem to make another for those with good will to do that.
....
Regards!

[fletchnews]

Comments from an Arado 120B user

Greetings Technos from a new chum to this forum. I found you while googling for "Arado 120B" and I'm eager to learn how your attempts at cloning the beast have progressed. Paul Foster, who created the original, told me 35 years ago that he had built various blind alleys and false trails into the circuitry to deter copying; but as he no longer makes detectors for treasure hunters I'm giving you my support and offering to buy a clone if you succeed. (I would not recognize a circuit board if it jumped up and squirted etching fluid in my eye.)
During five years hard use (1975-1980) I found 22 gold coins as indivdual targets; also a pocket hoard of George III shillings, as well as substantial numbers of medieval hammered silver. The machine was HELL to work with; an arm breaker until I had mine modified for use as a hip mount. It was also crucial to magnify and (if possible) illuminate the needle. Also - most important - to dig all signals for which the meter needle remained motionless. They were the good and deep finds.
I eventually abandoned the 120 in favour of a Tesoro Silver Sabre ... but not for depth; simply because I needed swift pick-up of shallow Roman coins in highly mineralized ground. I'm now disillusioned with Roman and hope to get back to lots of medieval with a machine that does not require a fifty-page instruction manual to set it up.
Edward Fletcher ... author of 1,000+ magazine articles on TH'ing and related subjects .. plus a book or two.

[Qiaozhi]

Greetings Technos from a new chum to this forum. I found you while googling for "Arado 120B" and I'm eager to learn how your attempts at cloning the beast have progressed. Paul Foster, who created the original, told me 35 years ago that he had built various blind alleys and false trails into the circuitry to deter copying; but as he no longer makes detectors for treasure hunters I'm giving you my support and offering to buy a clone if you succeed. (I would not recognize a circuit board if it jumped up and squirted etching fluid in my eye.)
During five years hard use (1975-1980) I found 22 gold coins as indivdual targets; also a pocket hoard of George III shillings, as well as substantial numbers of medieval hammered silver. The machine was HELL to work with; an arm breaker until I had mine modified for use as a hip mount. It was also crucial to magnify and (if possible) illuminate the needle. Also - most important - to dig all signals for which the meter needle remained motionless. They were the good and deep finds.
I eventually abandoned the 120 in favour of a Tesoro Silver Sabre ... but not for depth; simply because I needed swift pick-up of shallow Roman coins in highly mineralized ground. I'm now disillusioned with Roman and hope to get back to lots of medieval with a machine that does not require a fifty-page instruction manual to set it up.
Edward Fletcher ... author of 1,000+ magazine articles on TH'ing and related subjects .. plus a book or two.

I guess this must be you then? ->
http://www.amazon.co.uk/Edward-Fletc...099&sr=1-2-ent

Welcome to Geotech.

[fletchnews]

Amazon, etc...

Thanks for your welcome and, yes, my name (as Edward Fletcher,Ted Fletcher, Ed Fletcher) does crop up about twenty times on Amazon and similar sites, simply because I wrote books on TH'ing, bottle dump digging, rockhounding, etc. many years ago. Alas, there's no money for authors from secondhand sales, but I'm pleased that new readers still enjoy my old stuff.

[ApBerg]

Hello Edward,

You tell us you found 22 goldcoins.......and now there are no more.....
Most Thunters are glad they wil find just 1 gold coin..

About the Arado120 there are some techno's that made copy's... even better I think...but if they are willing to sell...
I never had a good succes with the Arado clowns, a gold ring at some 25 cm no more depth..
Long ago at Newbury I also bought a book from you...If that is you in that book at the river ... then you are also an oldy...

Best regards.
Ap

[fletchnews]

Gold coins ... one at a time

Helllo ApBerg ... Yes I found 22 goldies DURING FIVE YEARS OF VERY HARD WORK. I didn't say "and now there are no more". That's what motivates me to look for a clone.
And I too am delighted to find one gold coin ... at a time.
I'm 72 ... but please, no more biography. I joined this forum to find and buy a newly made Arado 120. Anyone out there with one for sale?

[ApBerg]

Hello Edward,

You have not seen this ?
http://aradodetectors.services.offic...m/default.aspx

I do not know how good it is....

Best regards.

Ap