Interesting Modified SDC2300 On Gumtree

Hi bush not grubstake
Maybe need some glasses on my head
But hello to grubstake aswell

Thanks for posting Bush. Be very interested in results on a goldfield with some smaller targets than 2 grams too.
Good luck with it & keep us updated once you get out to the goldfields. That's when you'll get a better idea of how it works.
The headphones might have a broken wire or something. They should be under warranty still if you have original proof of purchase. If not you might be better off getting a Phasetech adapter lead & getting some headphones of your choice. If it's the actual detector connection point that's playing up (probably unlikely) you may need to track the modder down to see if he can fix it? Minelab would most likely not touch it now.
Don't take the tape off the bum might fall out of it :lol: Just kidding - probably a good reason for it being there though.

I`m Back !
Here it is Coil Reports Minelab SDC 2300 using Lead without Head Phones.
I will indicate in ***** as 5 top reading and * as poor
Original Coil
Depth
6`` 1g* 2g*** 5g***
8`` 2g*** 5g*** 30g****
10``5g***30g**

12`` NF Mono Advantage 1gram did not register.
6`` 2g**5g***30g**80g**
8``2g***5g*****30g*****80g**
10``5g****30g****80g**
12``5g**30g*80g*
15`` ??????? able

note: for some reason the 30g & 80g did not respond well over 10`` but small faint readings
occurred with the thresh hold on minimum.
further more:
Tested
14``x 9``NF Mono Elliptical
11``DD Commander
14``Mono Elite
8``x6`` Advantage Litz Wire
( All of these Coils were VERY UNSTABLE.) Not GOOD.

Replaced 12`` NF mono everything back to normal.

My summary on 12``NF Mono Coil.fitted to SDC2300
It over looked 1gs at 6``.
2g readings at 8`` was good.
Screamed at 5g to 30 grams between 8``& 10`` up to 12``
Lagging 80g in all cases but did get readings.
Small sound readings 12`` 5g ,30g,80g.
lite Light up at 15``barely. `As Above.
Hope that helps some Diggers.
`i` know ` i` learn`t something.
Now just need some where to use it ?
Not shore if nuggets are found around the Coffs Harbour Region.
Open to suggestions i`ll even travel and go you halveezz if you are experienced.
Yep ! `i` now have a Learners License.
Bought that GPX 4500 in Braidwood QLD as well.Well why not bargain with all those coils.
New Tools of Trade.WTF.

Bush (The Risk Taker).. Welcome to the forum and thank you for your input about the SDC, I think you have somewhat answered a question many have longed to know about changing the coils on the SDC, the mixed results are interesting and inline with my own thoughts about increasing the loop size.
At least it is not a dud and probably could be restored to its original configuration if desired, only word of warning I offer you is have caution on running very large objects (nuggets) to close to the loop as it might be overloading the front end of the detector = sizzle fizzle poof.

G`Day Diggers,
A thought to share.
My son & `i` explored some areas in the Wild Cattle State Forest District.
Using this modified SDC2300 in old river beds.
Did not get any Gold besides some in panning.
It did however seek out small bits of rusted roofing iron and a 1.8 gram lead shot.
``but`` what i discovered was the detector has taught me a lesson on where gold could be.
All the targets were pinged in vortex areas, slip streams.Behind big boulders and rolled over tree roots.
Even more surprising it penetrates targets under large rocks ``Amazing``.
PS; The seller of this unit made contact in regards to the head phone issue.
He said the head gear is working he was not hiding under ground just in an area with no mobile reception.
So it seems he has upgrade to a new machine but reserved in commenting or just busy.
`i` notified him Prospecting Australia was seeking his input on his experience with this SDC.
So who knows he may come to the party.
My next adventure will be out there with the smaller original coil fitted as think in this area sub grams are more prominent.
Happy Hunting.

Not being picky here as I know your new to detecting but a couple of things:
- detecting in creek beds most people will opt for a smaller coil (or a suitable VLF with discrimination in junky areas) & the stock 8" coil would be better suited IMO so your thinking to refit it for this area would be a good idea.
- a lot of detectors will pick up small rusty bits of iron & 1.8gram bits of lead. Don't get too excited about that - the real test will be finding gold on mineralised goldfields. All good PI detectors will "see thru" large rocks etc. Yours probably isn't doing anything amazing due to the mod. Good to see it's helped you to work out where the heavies will collect.
- hopefully the seller gave you a fix for the headphone issue? One thing I overlooked mentioning before was making sure you "squeeze" the headphone jack to get get the correct fit to the machine.
- did he say why he upgraded to a new machine after a short time with the modded SDC? I'm guessing he's got a GPZ now?

Thank you for the update Bush, not that I have a interest in modifying a SDC but it is certainly food for thought for anyone that may be thinking of going along a similar path.

Peter.

thanks Bush, that helped satisfy a lot of curious minds and we`l be interested in any other coil tests ( other 8 or 10`s )
And What a Bargain you got with the 4500 for $2200

cheers and good luck with the new toys

Dave

Thanks for the update Bush

G`Day Folks,
Cheers for the input.
No Mbasko he is very reserved in commenting, who knows maybe he was the DH that modded the machine.?
I need to contact him again to question him where in Brisbane he sent the thing to be tuned or what ever they apparently did.?
I know `i` was tired & fatigued in that purchase.Drove from Coffs to Ipswich where i purchased a GPX4500 for $2100 with lots of extras & which is working just fine.
My thoughts to were to exercise both machines with my son when i head off to those major hunting grounds.

Recently explored some areas with an old school mate in the Bulahdelah Region.
He has been detecting since 12yrs of age taught by his father , we are both now in early 50`s .
Discovered some old gold mine shafts.No color though.
Pinged a horse shoe,small bits of fencing wire & bullet casing smaller than a .22 ( not shore what that could be. ?
Hard going over grown scrub ,very hot & humid.
Using that 12`` mono N/F on the SDC. So it seems to be working OK.
He liked the GPX 4500 and seemed though with the 8``x 6`` Advantage coil was as effective as the SDC on small gold test targets ?

My question of which dumb founds `me` is why does the 12`` mono & the 8``original coil work on the SDC but the other coils previously listed
send the machine unstable and crazy.
I find this difficult to fathom ?
Any views on this would be welcome.

I find it hard to fathom too? If I was going to put money on it I would have bet that something smaller like the NF Advantage Sadie 8"x6" would have worked ok rather than the NF Advantage 12"?
I think only Minelab techs or maybe the modder could answer it & I won't be holding my breath waiting for a response from either.
At least it works with the original coil & the 12". The end result could have been far worse.

My take on the coil issue is that the electrical specs of the 12" mono and the original coil are probably pretty close. I.e. The inductance, resistance, capacitance etc. The others are probably a little out of spec and cause the machine to be unstable.

I know in my experimental units that once you start to work with very sensitive input circuitry, the specs of the coil are critical. Personally I feel that you are really lucky to even get the 12" mono to work without some loss of sensitivity or stability. You may find that another 12" mono coil, even of the same type may not work as well due to the slight variability and allowable tolerances in each coil.

If I was going to test how good the coils perform I would be using sub gram nuggets i.e. .1 or lower as these seem to be what the SDC were designed for. Most of my experimental units will pick up the targets you used at the depths you mentioned previously.

I'm only assuming from Bush's previous comments but to me it would appear that even though the 12" is running stably there seems to me to be a definite loss of sensitivity in comparison to the OEM 8". I'm just reading between the lines though & without actually using it myself couldn't be sure.
The only benefit seems to be more ground coverage with no real performance gain or possibly even a performance loss?
The best & IMO only true test would be finding the same type of in-situ sub gram nuggets with the 12" arrangement. If you could consistently find them but deeper than the standard 8" coil then that there would be your performance gain.
Having the option to switch over to the 12" for ground coverage in open areas is still a nice option to have but I'd still be wary of what's being missed if indeed there is a sensitivity loss.
My thoughts still are that Minelab engineers married the MPF technology to that coil for a very good reason. If they marry it to an elliptical 14"7" or similar down the track then it would be something of interest.
At the end of the day the SDC & MPF is what it is. If you want better depth & more ground coverage you really need to get or stick with a SD/GP/GPX/GPZ.

Cheers Folks & thanks for the response.
Interesting Topic this has become.
Bugga though ! i would have preferred The Standard SDC in being able to be compacted in size plus the water proofing back up when canoeing ect.
Such is life for The Compulsive Obsessive Purchaser but OK i guess at that price $2300 & a 5kg bag of Russian Garlic.

I ran into a fellow prospector up at sofala a few weeks back he had a 2300 that had a coil mod that was done in quensland somewhere wouldn't say much bout it but it was running very bad wouldn't ground balence or quieten up said it has never been the same after the mods just a bit of input

Muzz !
Don`t know who you were talking to ?
Don`t know anyone else that has a modded SDC2300 & i never had it prior to the modification to compare how it was prior.
So your comment quote ``never been the same after the mods`` where did you get that ?
i know i made no comment to `you` on how the machine performed . What is your Christian name ?

`i` was at Sofala 3 weeks ago with a mate & he never got to use the unit or has he any experience with SDC.
The unit pinged Dozens of .22 bullet shells , boot tacks copper & the usual bits of rubbish..
No Gold but again being a newbie to detectors i don`t have the ear for smaller lighter signals yet.
The ground was hot , the temperature was hot , Storm activity going on and power lines in the area.
So yes the unit did have some moments of troublesome but it also purred prior mid day afternoon sun.
The previous owner recently informed me that Woody had completed the modification &`i`am yet to confirm this.
So as they say ``Muzz `` or whatever your name is ? Half of what you see & nothing of what you hear.
Making profound statements of negativity based on Blar Blar is only a reflection of yourself.
Question is Muzz what did you find or detect at Sofala ?
Question is Muzz who were you talking to ?

Reflection of your self Muzz , Sorry mate ` i ` must retract that statement.
`i` did read recently that someone with an SDC also visited Sofala.
`i` don`t know if the unit was modified or this was him / her.
Diggers.
So element of doubt to you unless you were just out for a dig on these units
`i` can say referring to my mod is that both coils the 8``Original and `12 N/F , both respond well and gets targets.
Had they been Gold it was in my pocket , i dig every target & bag all the scrap.
The unit in my adventure out there functioned great in early mid morning on both Private and Crown land.
I`m not shore if Sofala Hills is known as hot ground but all the bullet casings certainly seems hot and did `i` mention boot tacks.
`i` haven`t yet weighed one but they seem sub gram ?
` i `guess how does a GPX handle hot weather and sunlight ,storm activity and power lines ?
Maximum running temperature anyone ?
At present with this modded SDC , until i can find a professional operator that is willing to examine it .
Or alternatively to speak with Woody the unit may have been sent to him via Brisbane.
Hopefully Woody may come to the Party.
It`s been 2 years now since modified & i`m happy to send it to him for a re-evaluation.
Alternatively i`m seeking directions to other Pro Modifiers that are interested in Pay.
Help here would be appreciated.

:lol: there would have been many, possibly hundreds, of SDC's go over areas of Sofala now including myself. It's possible that another modded machine has been out there? If Woody is doing them there's probably a few around - he has plenty of detractors but has supporters too.
Sofala isn't overly hot ground but like anywhere can have difficult areas & suffer from EMI. By hot I'm talking mineralisation not temperature. I don't personally think temperature plays that big of a role with detector performance & in many cases people are getting afternoon spherics i.e. storm activity & mistakingly blaming high ground temperature so aren't really in tune with what's upsetting things. Hot bullet casings wouldn't mean much if anything. My opinion only....
GPX's run well in the Sofala hills in all prevailing conditions except torrential rain :lol:. Most operators have more difficulty with weather conditions than the machines will. The recommended operating temp range for a GPX is 0 to 45 & SDC is 0 to 50. Temps outside of those ranges would find most detectorists pack up before the detector will.

Good value mbasko,
i knew it from the start.

Hey Muzz !
Think i have worked out my issue whats yours ? lol.

DetectorMods
The trouble with coils
6 August 2014

The most obvious sign of a bad coil is if you get a signal from wet grass or green vegetation, this indicates a break down of the shielding inside the coil, but it can also indicate that the lead to the detector coil has some broken strands in the outer shielding. The breakage is caused by overly tight cable glands cutting into the cable over a long period of time, this is mainly applicable to older style coils as the coil manufacturers these days are changing the way the cable mounts into the coil housing.

Nearly all coils have shielding made from Graphite or fine Carbon mixed into a carrier material to make a partially conductive paint, depending on the way the coils are made this paint is either applied inside a mould and an expanding foam surrounds the coil wire winding and then sticks to the paint on the mould or the paint is applied directly to the foam with a spray gun or paint brush. Some coils have the shielding done with paper cut outs painted with the shielding paint and glued to the foam and coil assembly. In all these coils there is a difference in the rate of thermal expansion of the coil housing and the foam core with the shielding paint, over time with thermal cycling, the two parts rub and can reduce the conductive paints effectiveness and cause ground balance issues and general coil noise.

I have included some pictures of coil cable cut by too much pressure on the cable gland. A coil that has had part of the bottom shielding paint worn away by rubbing against the coil housing, and a coil where the shielding on the side of the coil was never there in the first place, this would of sounded off on grass and greenery.

Most coils can be pulled apart and inspected for issues, most coil housings are made from ABS plastic and are glued together with MEK that melts the plastic parts together.