Interesting Modified SDC2300 On Gumtree

[user 4485]

Hi Bush - just wondering if you've managed to pick up any gold with this modded unit over the past ~3years?
Are you 100% sure there's no wires to the button? There's a number of wires in that area & 2 should be for that button. Your previous questions about the button & wiring led me to assume you thought they had been broken or disconnected previously on your modded SDC?
I'm certain that it does what Minelab says (fast track button) as I've now owned 2 different SDC's & if becoming erratic the fast track button + pumping has settled it quickly on many occasions although using it periodically in normal detecting is IMO largely not necessary.
If the button isn't connected (doubtful) then the process of pumping the coil with the constant auto tracking must work well.

 

[Bush]

Hi Mbasko,
Great to hear your still kicking.
`mate` when i probed inside the unit some time back.
I noticed there was no connection to that button.
There were a couple of wires one to the Noise cancellation and threshold and low battery indicator.
I traced all the wiring thoroughly.
I at first thought it may have been chopped as part of the modification.
This is why i announced it earlier as if it was not working would the unit still work.
You validated that it would and i accepted your comment.
I have viewed that area with a magnifier glass and could not see any penetration holes that would lead me to believe that any wiring was in place.
That area leading to that button is a seal type of poxy resin no indication At All that any wire was present.
This is why i was so happy when you stated that the unit would still work.
From Bacchus comment earlier in the piece sort of validates what i`m suggesting.
Great to have you back Mbasko i may jostle and joke around at times but i don`t tell lies. O

 

[Bush]

Hi Bush - just wondering if you've managed to pick up any gold with this modded unit over the past ~3years?
Are you 100% sure there's no wires to the button? There's a number of wires in that area & 2 should be for that button. Your previous questions about the button & wiring led me to assume you thought they had been broken or disconnected previously on your modded SDC?
I'm certain that it does what Minelab says (fast track button) as I've now owned 2 different SDC's & if becoming erratic the fast track button + pumping has settled it quickly on many occasions although using it periodically in normal detecting is IMO largely not necessary.
If the button isn't connected (doubtful) then the process of pumping the coil with the constant auto tracking must work well.

Further more;
No gold found Mbasko not as yet.
Not for the lack of trying.Found just about everything else but.
See i`m not quite out there yet. A few adventures in toll.
What i said to myself is that i`m not going to get old and spend my time drinking in a bowling club day in day out.
So this Prospecting thing i`m still gearing up for.
So i`m still busy finishing renovations on my home.
Restoring and fitting out an Arkana 75 series 4WD to travel in.
`i` have the detectors to get some practice in prior departure.
Not shore when but that is my future goal.
Life`s short and i have not done a lap around OZ yet.
Check out me mate on You tube.Get down and dirty prospecting.
He`ll probably be doing the tour too.

 

[AuMan]

Hi Bush,

It sounds like the coil plug has been wired correctly.

The false signals from your hand happen because there is no shielding around the control box and the capacitance from your hand has an effect on the coil receive.

With the breeze causing your machine to become erratic, that is a thing and it happens to all ML detectors.
Those curly cables will also cause some false signals as they compress or stretch out.

With your standard coil, you will have to try and source some proper mono coil cable. I think Coiltek in Maryborough may sell it, however it could be a bit of a job to get it all installed and everything working right.

With the GB button, it is indeed connected. The cable that goes up to the control panel, first connects to the gb button, then 'T's off to the control panel. There are 2 wires at the plug inside the detector and 3 wires that go to the control panel, one of which is connected to the GB button(and ground). The controller in the control panel must be capable of one-wire communication as well as receiving its power from that same wire, quite nifty really!

I have now bench tested a range of coils on the SDC.
The Sadie coil is a good contender to replace the stock sdc coil.
The 12" Nugget Finder Advantage might work ok.

If using a coil that is not properly suited to the detector you will find that it may pick up ground noises that aren't normally there and a loss of sensitivity.

The thing is, in its standard form, the SDC is optimized for small gold and small coils.
That being said, I have made some tweaks to this one I have here and can even get it to run a Nugget Finder Advantage 25" coil!

So, during the long weekend, I will be doing some field testing running the SDC with various coils. Perhaps it will be a total failure, however I don't think it will be. I am very interested to see how it behaves and hopefully capture some useful footage :goldnugget:

BTW, I know the word "mods" has a bitter taste to it, but that was nothing to do with me

Cheers Mick

 

[Bush]

Thank you Auman,
I really appreciate the input forwarded here.
`i` find myself extremely lucky to receive correspondence from yourself and members on Prospecting Australia.
Coiltec did help me out with some cable but don`t tell anyone as it maybe against their policy.
The cable though is a little different from Minelabs Standard.
Coiltec`s has it`s 3rd wire insulated / shielded maybe finer in gauge also multi stranded.
So i don`t know the up`s or downs in tolerances ect. Should be better my thoughts.

Just wondering if anyone knows if i can reconnect the cable to the coil base connections without splicing the new to the old.
I`ll also have to make up some new conductive pads for the coil.
Found some carbon laying around.Left overs from distilling filtering system.
`i`ve tested its conductivity and it seems very responsive.
I have ground it down to a powder.Now just have to find the right liquid solution mix ratio to paste on to the new pads.

``In All`` the work carried out modifying the head shaft fitting ( prior my owner-ship of this detector ) to adapt other coils was actually quit impressive.
It would not have been an easy task cutting and re-shaping that fitting knuckle to achieved the adaption.
Even the re-wiring in it`s self is an accomplishment as it`s operations is like micro surgery and not for the faint hearted .
` i base these comments on 37 years as a carpenter/builder and some electrical apprenticeship studies.
Unfortunately `i` failed in the lab work examinations.Tough calculations they were.

Not shore about the 6`` sadie coil when i first tested the variety of coils that one did not respond very well.`i` may try it again later some time.
Still would love to find a large Spoke Coil that responds to the SDC2300.
That ``16 NF `i` find tiresome in weight.Not totally verified working order on mineralized ground as yet.
Hope you have some positive results over the long week-end with the coils Auman.
I think we are All awaiting more test results. :Y:

 

[AuMan]

So, the Sadie coil, bolts up and finds gold! Literally put the coil on the detector, fired it up, put it on the ground, weeeoooo. Nah, gotta be a pellet. Cranked up gain a bit just coz, oh that brightens it up some, take a scrape, out, in my hand, 0.03g tiddler! Unfortunately I couldn't keep that kind of run going!
The Sadie worked no problems at all, same with the 12" advantage, with the detector in stock standard settings. Found a small piece of lead shot with the 12" at an inch or two, gain was up a bit.

The 16" 18" and 25" Nugget Finder Advantage coils worked well with my frequency mod, along with the gain. Salt timings seemed to give better depth on my 8.6g test nuggy and was very comparable(I ran the same coil and test on a 4500) to a 4500 running enhance. Testing was done at Avoca in some not so mild ground and I was really impressed with how well the sdc maintains its ground balance.
Unfortunately I didn't find any targets with the bigger coils on as the area I was at has been hammered to death by every man and his dog! However, seeing how it handled the ground there gives me confidence that it would. If anybody has a spare patch with some golf ball sized nuggets in it that they want to give away I'd be more than grateful O

 

[Eski]

Good stuff Auman, so frequency and gain mod .... any filtering changes to make it smoother? and how did you go with the 12 inch evo?

how did it compare to the f1a4L3

 

[AuMan]

Hi Esky,

I haven't done anything as yet to make it smoother, that is the next job on the list. It is the one thing about the sdc, it's a chattery little thing! In fact, it is also quite heavy, it feels much better balanced with an 18" coil attached to the end!

The only Evo tests I have done so far were on the bench and for some reason it doesn't like them, I didn't try them on the ground. I haven't delved into the transmit and damping circuit on the sdc yet, I suspect there are some differences there.

The F1A4L3 is a hard detector to beat! That nice smooth threshold and sensitivity just gets me every time. It still detects a 1.5g specimen I have here much better than the sdc. If the SDC can be quietened down then things may change...

Cheers Mick

 

[Eski]

Cool , the SDC is a neat lil package that could be great if it got some depth and stopped being chattery...
Good stuff. may the gold be with you.

 

[user 4485]

The SDC is great now for those who get to know it!

 

[10fp]

Great to see Mick working on mods for it

 

[user 4485]

Great to see Mick working on mods for it

Looks like people want it turned into a GPX to me?
The SDC is superb at what it does & those who know it well do very well with it as is - no mods required.
Want a smooth machine with interchangeable coils + better depth then your better off selling the SDC & buying a GPX. :Y:

 

[Bush]

Well the mechanics did the tweaks to small 4 cylinder motors to match up the speed to the big V8`s .
Anything is possible but at what expense.
RPM vs Torque in that case.
What i haven`t noticed on comments on using the SDC2300 but mentioned earlier on this post when i attempted depth tests on various coils.
Is when over the deeper targets and the sound signals faded out in depth.
There was still indication on the lights on the instrument panel control box indicating a target.
Not something one would normally notice as we tend to focus on the sound while our eyes are on the ground sweeping.

 

[madtuna]

Great to see Mick working on mods for it

Looks like people want it turned into a GPX to me?
The SDC is superb at what it does & those who know it well do very well with it as is - no mods required.
Want a smooth machine with interchangeable coils + better depth then your better off selling the SDC & buying a GPX. :Y:

Spot on!

Have been following with interest a bloke here with an SDC and the new 14" x 9".

Using my standard SDC I located 6 targets for him, 5 were gold and 1 was a tiny chip of a loader bucket. We could not hear 4 of the gold targets. The 1 gold target we only heard because we knew it was there, the bucket chip was clearly heard.
No way would the nugget we did hear have pulled us up had it not been located first.

On this same spot I found 12 more small pieces that day while he found none.
The bigger coil certainly loses the sensitivity of the standard coil and he's pretty confident he's not getting bigger bits at depth either that he's getting with his 5000.

 

[Bush]

Yep ! Seems to be the case.
Today the over head power lines were shut off most of the day.
So i decided to place the ``16 NF on the GPX4500 and sweep around the paddock.
Placed markers on around a dozen targets ``not`` that i believe there`s gold there.
but more so probably old farming bits and pieces.
Then swapped that ``16 coil onto the SDC .
At least half of the targets i would have walked over.
Maybe with the headphones on the SDC it may have had a chance.
`i` believe the ``12 NF would have but i have not dug`em up yet for any depth test.
Power is back on now so GPX is out of the question.
Try again with the SDC with ``12 NF to see where it`s at.
Cannot compare the standard ``8 coil as repairs are not accomplished yet.
Living in Hope. :brokenh:

 

[Bush]

Pandora's Box.
SDC 2300 Coil Innards .

 

[Booney]

Gday Bush , interesting to see inside the sdc coil , may I ask what is it your trying to do in there ? I've been following this thread as well as others regarding modifying the sdc with different coils , can't say I'm convinced it's a good idea, that's just my thoughts ,each to there own and nothing ventured nothing gained . I'm only guessing your trying to reattach the stock sdc coil back to the sdc , hope this all gos well for you and interested in your progress . Having owned and used the sdc for nearly 5 years I can vouch for its amazing ability to find the small bits of gold other detectors miss. I have found gold every time I have taken it out and have found hundreds of little nugget with mine . I'm sure when you get the standard coil back on your machine you will see how good the sdc is at doing what it does best , that's sniffing out the small bits .For larger deeper targets I turn to my 4500 . I have found some larger bits with The sdc up to .5g .You will know when the sdc is working properly you'll start finding lots of bird shot but that's all part of it .good luck with getting it back together mate , keep us all posted how you go .
Cheers Booney

 

[Bush]

Hi Booney,
It`s not as bad as it looks.
The cable was well over due for replacement a long time ago.
Nicks & Abrasions on the insulated and shielding wires was effecting the unit response.
Having the same issue with headphone leads.
`i` really had no option but to take on the adventure and there is always a surprise probing into the unknown.
`but` to tell you the truth `i`have a habit of dismantling things and re-building.
Probably there is some name for this phobia of mine. ha ha.
In most cases success is usually on my side.
Cameras , watches and Relation-ships `i` tend to fail at their just so intricate.
One trick is to mark and tick off everything.
All the positions and components extracted in sequence using multi color permanent markers.
`i` did this when replacing valve guide seals on a Mitsubishi motor on a 6G72 / 24 valve overhead cam -without taking the head off.
All the motor re-builders i spoke to said it could not be done on that model but i did it successfully.
Had no choice either in relating to this coil.
OBQ (one big question ) i have HRN ( here right now ) is about the faraday shield pads ?
i would like to replace those carbon pads with a full wrap around the coil winding's ``but``
Is there mean`t to be a gap between the upper and lower conductive faraday pads. ????
`i` think so from what i could see `but is that a requirement or just Minelabs coil makers method of construction.
:8

 

[Bush]

By the Way the Dogs name was Smoke.
He was on Channel 9 & 10 news and Wide World of Sport. Mid 90`s
He could count to 10 fluently and add 2 + 2 wolf wolf wolf wolf inclusive of many other slick tricks.
They say Dogs Personify their Owners. :gemstone:

 

[AuMan]

Hi Bush,

:8 What have you done??!!

Now, one thing I didn't know until very recently is that Minelab are using a separate wire for the coil shielding and joining it to coil ground at the coil plug.
Conventionally the coil shield is tapped off from the ground connection to the coil where the coax joins to the windings. It would be interesting to compare two identical coils, one with the extra shield wire and one without.

The carbon painted cardboard, leave it as it was. The gap is there for a reason. If the join the top and bottom together the shielding can start to look like a target and the coil won't settle back to 0v in time.
When you re-assemble the cardboard and go to attach the shielding wires to it, you need to make sure the wires get a good connection to the carbon on the cardboard.
In the past when I repaired a few coils, I have used a conductive silver pen to paint over the drain wire to ensure it had a good solid contact. After it dried properly I then just covered it with more masking tape.

For the cable, how bad was it? Is there still a good section? If it was broken anywhere it was most likely where it pivots down at the coil.
You may be able to straighten the curls out by stretching the cable out straight and gently warming it up with a hot air gun. Too hot and you can melt the insulation, too cold, it won't stay straight.

Good luck with it!

Cheers Mick