Modified SD2000s to GP3000s

Well it has been 5 years since my first posting on this forum when I congratulated Ismael for opening up this website for operators of his modified SD2000. Since then I have added several postings of my thoughts and experiences with some testing results thrown in for good measure. Also other members and their contributions to the forum has added valuable insite.

Ismael has changed the format of this site a couple or so times all for the better and although the forum ticks over at a snails pace Ismael has keep the site alive to this day so once again well done Ismael.

I have just finished watching another of Woody’s YouTube videos demos from a SD2000 modification to the latest on modification to a GP3000. The 1st mods on a 2000 were to increase sensitivity to smaller targets to match later models and now mods for the 3000 to do the same. It will be interesting to see if further 3000 modifications will match the overall depth potential that further 2000 modifications produced during in-ground testing in Victoria even up against the 4000 series.

As Ismael named this a Minelabmods SD/GP information site than hopefully some modified GP3000s in-field reports and test results can filter through onto this site also. Of course I am a little bias since I own a modified SD2000 and a stock GP3000 with a wait a see on its modifications.

Gary.

Gary I have enjoyed your constant contribution to this forum and without it Ismael may have thought to close the forum down by now due to lack of interest. It does look as though there are very few modified 2000s being used now even Ismael gpm models as no one says much about them here anymore. I gather from what you say you use a 3000 more often than your gpm 2000. Anyway I off to sit on the fence once again. Brian

Brian I too have enjoyed posting here and wish there was more activity. It seems so, as you mentioned, there may not be to many modified 2000s out there still in use.

I see Kris over on the GoldprospectinginOz forum says he is still operating one of Ismael's modified 2000s. It would be good if Kris would post here on a regular basis and therefore fly the flag for faith in his 2000. I still have faith in my old girl and wonder what differences in the number and size of my nugget haul if I had not bought the 3000.

I have become familiar with operating a 3000 and now confident with mono coils and receiving some success as well. When operating my modified 2000 I was reluctant to keep a mono coil connected although since my experience with the 3000 I feel I would not hesitate using a mono on the 2000 by running its mods accordingly.

Actually a few day ago I was playing around with my 2000 indoors using its 11"DD to help cancel any noise as I performed some air tests using a Silent Threshold. I then tested different Gain settings while in silent mode on both small and large targets as well to compare any interference. I could not increase Gain above 50% and my air results still showed to me that using a minimal threshold produced to best results over nil threshold.

I have tried using nil threshold with the 3000 while out on the goldfield but the mineralised conditions kept breaking through as threshold and was to much of an annoyance.

Now back to my 2000 and another observation. I was unable to connect my 3000's 6 volt gel-cell battery via my external Sakina variable voltage regulator even when it was set at 6 volts. For some reason when I switched the 2000 on its threshold started surging and its low battery light started pulsating as well. However once I connected the 6 volt gel-cell straight into the detector it worked fine. I have no idea why this was so?

Kris have you tried using a zero threshold setting on your 2000 while out on the goldfield with any success and has your GPM Gain settings been of any assistance where you detect?

GaryQ.

Gary to answer your last question first,yes I did try last time I was out to run zero threshhold it worked ok but there was a lot of iron trash in the area and it came in with a bang and would rattle my brain with the amp. at max.I think I will stay with a threshold.
Here is a run down on how I set up the machine, Commander 245mm DD Elliptical 99.9% of the time.
Channel,1 at max.
Channel,2 75% to max.
Threshold Low
Voltage 8.5
I think minelab would would have a market for a new model that was as simple as this to set up LOL
Gary mono coils here in Vic. are a big no no for machines other than the 4000/4500.
You may be interested to know I purchased a AI/Salt coil last week so I can do tests at home in the shed,works quite well but doesn`t like the cheap chinese fluro. globes LOL but still 100% over a mono and much better than a DD,and at odd times maybe handy in the field, you can pick them up real cheap.
I don`t do much depth testing building better earphones and external speaker systems is my passion maybe you saw one of my setups on Pos/oz.
Anyway I`m still quite happy with my old banger and don`t see a need to upgrade at this moment it`s found me twenty small nuggets over the last month I will try and post some photo`s I tried last week but it said the file was to big, I will have to get the daughter to check it out for me LOL
regards
kris

Kris I finally got around to a reply and thanks for the run down on your 2000 GPM settings.

I have a Commander coil also but it is the 200mm mono Round and got to try it out on my Isy modded 2000 when I loaned my 3000. I was surprised how smooth the Commander mono ran over some cranky ground considering Gain was wound up 75% using Freq 3 although had voltage in the 6 volt range. I believe the Commander series are a very competitive coil and it is a shame the larger ones are on the heavy side in weight.

It certainely seems the 4000 series with their new timings have done away the need to operate with the DD coil in extreme ground conditions such as in Victoria. Aluvium's results with a mono coil are sure impressive under these conditions.

Yes I did read your posting on Pos/oz regarding DIY headphones and just goes to show what ingenuity can produce. I see you have a passion with building better audio systems and you mostly use a Telex underchin system depending on certain weather conditions.

Previously I used an Audio Telex set of headphones and followed further advice to rewire the transformer in the input earpiece to parallel instead of in series, which did increased the volume level from my 2000. However I see you found that wiring those speakers in series for your DIY headphone they then almost blew your head off.

I have returned to using headphones after a stint with an external speaker system although my headphones only have an impedance of 32 ohms although the external speaker was only 8 ohms.

I wonder what impedance those speakers used in your DIY headphones are that produced the awesome results that even Zed Troy confirmed to you.

Impedance mostly optimises volume so would features such as the speaker efficiency, magnets, materials and durability be the most important factors.

Kris in your experience what do you consider to be important factors for a good earphone.

Gaz.

Did not expect to get answers to my questions, so I will stick with my thoughts.

Hi Gary & Co,
I am now at the stage where I reckon I'll go back to a 2000 very soon. I'd really like to try Izzy's latest 2000 mods...if the sensitive smooth switch works well, it should handle one of the new 12" NF ellip mono's. This is a killer coil on small gold, I've never seen anything like it! Case in point: 16 bits of gold in one afternoon using a 3000 with this coil ON A SPOT I HAD ALREADY GRIDDED WITH MY OLD 2000GPM AND AN 8" MONO COIL! I also got 82 bits of tiny junk....mostly lead shot and .177 air rifle pellets. The spot was only 2 acres or so. Plenty left there for sure!
Izzy, how much for your new mod?
Left you an email but no response.Any cheaper if the BJ mods are already done to the unit?
Cheers, Dwt

G'day Pennyweight,

Ismael's latest mods sure sound enticing and hopefully Izzy can give you and the forum some idea of costings.

My NF 18" round mono has now taken over as my favoured coil on my 3000 and snagged some nice gold for their size at good depth on my last trip to Clermont so good to hear another Nuggetfinder is performing well.

Do you think the NF 12" elip mono would it be any deadlier on small nuggets than the Commander 8" mono I been also using on my 3000 to date.

In other words had the 3000 with the 8 " mono also been over your nugget spot in question and missed some of those nuggets the 2000GPM managed to miss.

Regards,
Gary.

Hi Gary,
yes, the NF coils are the go lately here in Central Victoria....the 18" round mono and the 24X12 ellip mono
are producing the goods for the pro's seeking larger, deeper gold.
What I was stunned to learn was the 12" ellip mono being able to find so many tiny bits DEEPER. It is so superior in finding species too. 4 of the bits I got from my patch were in quartz....2 were on the surface! Remember, I gridded this spot....the 8" mono on my 2000GPM didn't hear any of them! My modded 2000 beat the arse off any GP previously. The key was definitely the coil. What clinched it for me was the fact that the spongy gold species and so many .177 air rifle pellets were found...these are notoriously difficult to hear with any machine or coil combo because they are hollow. A super modded 2000 with this coil would clean up any small gold in the first 8" of dirt I am sure! I can see ounces in my jar in the not so distant future Cheers, Dwt

Hi Guys
I have'nt posted here in ages,but I have just been reading that you guys seem to be able to run nuggetfinder mono coils on your gpm 2000,s
I bought a woody modified sd2000 from jack lang a little while ago and before it arrived I messaged Woody to ask which coils worked best on his modded machines.
he told me a big coiltek mono was the go and that nugget finder monos dont work because they have the wrong Q factor.
I have a coiltek 24 inch mono that works in both the high and low frequencys.
i also have the 11 dd coil that came with it from jack and a coiltek 17x11 wallaby dd coil.
both the 11 dd and wallaby dd coils will not work at all in the lower frequency (the machine just goes nuts)
I borrowed a 18dd nuggetfinder coil just to try it out in the lower frequency,and it worked smooth as glass.
but it picked up mineralisation with a sharp target like signal.
I told Woody about this and he sent a brief message saying.

The SD2000 is only meant to work with big Mono coils.

I just would like to know your thoughts
As I am in victoria which is hot for monos, and I see that you guys can also use dd coils on your gpm 2000,s
I would love to be able to use a double d coil in the lower frequency and get the full potential out of this detector.
I am sure if I can get the coil combo right it will be a kick ass machine.
Thanks from Scott.