karelian

Once mounted, it is difficult to remove the 6" concentric from the GMX, it is simply that good. Some images of the coil mounted on the GMX and other images for comparison. I'm very pleased Garrett has continued with the 24k, worthy of a second chance.

Only a matter of time before these start to ship out in Australia. Full credit to Garrett for doing a better job in marketing and sales, they are moving fast. Now available for sale in Australia.

Snake Skinz are not waterproof, it will shade the cable preventing or slowing further UV damage. You can still inspect the coil when the Snake Skinz is on. I repair coils with tape, heat shrink rubber tubing, liquid rubber film that is painted on. All effective but look terrible, the Snake Skinz is purely cosmetic in that it improves UV protection and appearance. I applied these remedies before the cable broke and exposed the inner wires. Living in Australia I think it is a good preventative for sun damage, whilst looking kind of cool. All the best.

I had one coil that had a cable that was badly sun burnt and brittle. A bit of heat shrink and tape fixed it, but looked nasty. The Snake Skinz covered the mess nicely. Looks like a useful solution to a common problem. Probably will fit most coils, certaily good camo for repairs. All the best.

Curl, try Snake Skinz as they sound like just what you are after.

I like the Tdi Pro and Tdi Sl, but I am a beach detectorist who sometimes likes to go bush and explore the goldfields. So having used these machines almost under 'all conditions' I have some idea of how they perform at their best. Mainly on the beach, that is where they make the most sense. They will however allow decent peformance when relic hunting and prospecting or even coin hunting on specific locations. For an PI machine they offer us the ability to set the machine up for a variety of conditions. If I ever hunt in the UK for Roman or Viking treasure, I'll have at least a Tdi Pro or SL with me. This versatility, ability and the price were major considerations. As I am slowly moving towards 'gearing up' with the addition of a 4x4, camper trailer etc, the idea of spending tens of thousand on these items and then not buying something like the GPX 6000 does not really make sense. Minelab make excellent prospecting detectors and investments in technology that translate into increased peformance. For the beach I will probably continue with the Tdi, it does it so well. Other companies may step up to the plate and offer an alternative to the GPX 6000, I am not in a hurry. Pity Whites is gone but Minelab is doing well in advancing the game for both professionals and folks like me who consider it a hobby. I no longer shoot film in my cameras, digital all the way and I'm better for it. A GPX for prospecting and the Tdi for the beach. Technology moves on and more often than not, it is to our benefit. Now begins the 'long' wait for GPX 6000 machines to appear on the used market. I'll keep saving and wait for the opportunity to make the updates. Until then I'll keep using what I have, still bringing home some good finds and having lots of fun in the process. All the best.

Must mention that whilst a small DD is great, a small six inch concentric will offer excellent results. On my GMX that flat bottomed coil is nothing short of superb. New Garrett 24k customers should chase up the older coil or hopefully new ones will soon be on offer. With the MXT I often used the Eclipse 5.3, even when the ground made it noisy. The 24K flat bottom designed six inch concentric is nicer but the older Eclipse performed well, despite being a bit fat or chunky in comparison. If the ground will allow it, outperforms all DD coils for depth and sensitivity on the smaller targets. All the best.

Tony I have managed to run the MXT in awful ground, the key for me has been the smaller 6x4 DD Shooter coil combined with lowering the gain. Just lower the gain until the machine is stable. In trash I use audio disc, zip vs grunt. Start by digging everything and getting an idea of the type of rubbish in the area. Some areas have few if any bullets, pull tabs or other modern junk. Sometimes rusty iron, old tin cans, rusty tools or even metal gold pans dominate. After digging everything in trashy sites I'll go hard with disc if modern trash dominates or continue to dig everything if 'old' trash or 'relics' are present. In gold country the 6x4 DD is my go to coil with the MXT. Great for crevicing and bedrock. Your MX7 with a small DD should give you an idea of what is possible. Some good advice on this thread, no need for another machine, just mount a small DD coil. Tony what coils do you have for your MX7?

The 6 inch concentric coil on the 24k/GMX is fantastic, excellent in moderate ground but still usable as the ground gets hotter. For hot ground with trash, the 6x4DD or an equivalent would be a better choice. A time goes on there may be more coil choices available. WA is an area that makes any VLF hard work, not sure the 24k would be any different. For exposed bedrock, surfaced areas or very shallow ground the pain may be worth the gain. Trashy areas combined with very nasty ground, I'd walk away or reach for my MXT with the 6x4DD. I know the MXT well and have more confidence with it in such a demanding scenario. A few more hundred hours with the GMX, maybe I'd have a go. Tony, put that small coil on the Xl Pro, run in hot rock reject, SAT GEB, with low gain and see how it goes. I took mine out to Dunolly for a run, found a six pence and a half penny hidden among trash. A bit of fun. It's old tech but it id's iron well enough. I'd be very interested to see if the old girl can run smooth on the Mars landscape you have out West.

The GPX6000 sounds like a winning formula, performance matched to light weight and good balance.. Tony I'm keen for people to buy a load of them, in a year or two I will be looking at the used market. Sometimes it pays to take a step back and let the dust settle. Time is on our side, more information, accessories etc I will make a better educated purchase when the time is right. All the best.

There is no numeric answer, we set the gain to match the ground conditions, the hotter the ground the less gain.. In hot ground a gain of 3 or 4 is decent for the first Tdi machines and the Tdi Pro. Don't fall into the trap of thinking you need to have maximum gain to get results. A smooth and stable machine is usually the best bet, even if it comes at the expense of having to search at a lower gain. When ground balancing do it with a lower gain at first and then experiment with the gain to see how high you can go without making the machine unstable. Every time you adjust the gain, repeat the ground balance. Every time I go to a new location I experiment with the machine to see which combination of threshold, ground balancing and gain works best. Always carry a test nugget, I use a 1 grain gold ingot.. Give yourself a bit of time to experiment and play at the start of your hunt, to see what settings work best for that location. The type of gold found in the area, the amount of iron trash etc determine Hi Low or ALL conductivity and coil selection. Again with the original Tdi, in hot ground a threshold of 3 or 4 sounds alright and I don't think you are missing anything.

Just a bit of information on the Vaughan area as shown on old and new maps. The drone footage was over Ballarat Hill with the maps showing the same area.

The Porcupine Ridge Rd area is reputed to have produced some larger gold. Surprisingly little historical information compared to other areas. A very interesting area full of promise still. Lots of bullets on the hillside above the river, rabbits still hopping around. Met a very large brown snake who didn't stop to say hello, thank goodness.. I'll be spending some more time in the area. The mineral water at the spring tasted awful.. not going back for seconds. Ballarat Hill is quite distinct and even more so from the air. Pity the larger portion being on private property. Took me a while to work out the boundaries but once you figure it out there is still a decent area to detect. Moving south there is less private land and things open right up. The lack of a 4x4 has hampered my efforts to some extent but I've got a decent pair of boots that compensates. I think I left a few bits of my car on the Wewak Track. The sound of my car crunching and scraping on rocks is equal to fingernails on a chalk board, just more expensive. The situation with the bridge is a disgrace and symbolic in so many ways with local governments priorities not reflecting community needs. Years ago I drove over the bridge on a few occasions and it always looked as if it was ready to give way.. I've just spent a bit of time in Eastern Victoria and the scrub was so thick it was challenging to swing the detector.. with a Red Bellied Blacksnake for every hundred meters of creek.. Vaughan is a much easier place to prospect despite the occasional brown..

I've got all my fingers, like to keep it that way... a healthy respect for those high rpm propellers. The Mavic is so stable that hand launches and retrievals are almost routine with some operators, I'm not there yet..

I'm using a DJI Mavic Air, mated to an ipad with the controller. I carry four spare batteries and spares etc Everything fits into a smallish Pelican style carry case to keep dirt and dust away. Because I always fly within visual range as per rules.. I sometimes use a spotter with binoculars, safe range out to 1 km, often much less. I use mining records and maps to find locations of interest. Google earth narrows it down a bit also. Finally once I have arrived on the goldfield the drone allows me to fine focus my attention on specific locations. I print out a hard copy mini map of areas I intend to search, then use a pen to mark areas of interest as I search that area by drone and on foot. A printed map works for me, digital alternatives on the ipad are used in camp to plan the days search. Research and planning.. analog and digital. Quickly learned that large metal objects like cars and hot mineralized ground play havoc with the drones electronic compass. Calibrate well away from the car and off the ground, then launch the drone from a tree stump if available.. The birds eye view helps me find the best parking spot and camp site. Quickly identifies the boundaries between private property and public land. Just a very useful tool in new areas. All the best.

The importance of using a good quality metal detector suitable for prospecting has been widely explored in great detail. The introduction of the GPX 6000 highlights the gains in technology and thank goodness, ergonomics. Weight and Balance, at last. Matched by performance and cutting edge technology.. The one fact remains that at the end of the day the key is to get the coil over the gold. Some truly magnificent gold that has been found, could have been detected by any half decent prospecting machine. Still we should invest in quality and the new Minelab sounds superb. We need to utilize every tool at our disposal. Often after extensive research, Google Earth images, maps, books and word of mouth can all lead us to a certain goldfields. When we arrive there is a lot of suitable ground to explore. Perhaps too much ground and not enough time to give it the attention it deserves.. In an effort to narrow the search I have started to use a drone when exploring a new area. It allows me to gain perspective, to more clearly focus on areas and features of interest. When the terrain allows it, this will same me a lot of time and increase my odds of putting a coil over a target. Viewed from the ground vegetation can mask features which kind of pop up when viewed from the air, the drone allows me to focus on a smaller area of interest.

They say the devil is in the detail. If you are handy with an soldering iron and have young eyes then it does not really matter which style of pug you go for. The big chunky ones have the plus and minus connectors labels on them, are much easier to connect and for anyone with arthritis or poor eyes are recommended. Small and finicky vs large and practical, my opinions and experiences only...

I've been using my brothers smart charger with this power pack, had to replace the dedicated chargers connector which plugs into the male 2.1mm plug. A faulty female plug needs to be replaced, still waiting for the post man.. When the charger arrived it came with a male 2.1mm plug, which I swapped over for the female connector, which worked great for a couple times and then failed. Maybe I was a bit rough or it was too delicate, not complaining about a part that cost one dollar.. Ordered a different brand female plug, looks a bit more robust.. just like to get the parts right before final parts list and review.. Again the dedicated charger works with the 5 x 18650 battery pack and is the better option for those of us who don't have expensive smart hobby chargers.. More to follow, all the best.

Love these orange packs. I bought two back in 2017 for my Tdi Sl. Now use them in the Xl Pro and MXT. So three years without any problems. Yes it is a very good idea to use quality protected cells, good 18650 cells are an investment and cannot be recommended highly enough. Shaves a bit of weight off as well compared to alkaline batteries. The voltage is not too high and there is enough power to go for days on end with the VLF machines. The ability to swap out for fresh cells in the field is an added bonus when using the Tdi Sl.. You are on a winner.. All the best.

I tend to play it safe with my machines, but the modified Tdi Pro has been the exception. I've pushed that baby hard, like driving a rental.. Since it was already modified I just wanted to see how much the higher voltage battery could push things. Baby steps all the way, just that bit extra depth every time. The Tdi Pro just hits hard all the way, maximum performance until the PCB kicks in at 16 volts. I agree Tony that it is not worth pushing safety margins for a few extra centimeters, plan on enjoying my machines for some time yet. Who knows a few years from now I might cast an eye on a second hand GPX 6000. Until then I'll have at least one Tdi Pro to swing on the beaches and the goldfields. Last trip with this machine will be to a less well known mining area, I'll work around the edges where I know there was large gold. Large nuggets found between two and three feet. I'll mount the larger 14 x 8 Digger coil and run her hot until the PCB spoils the party at 16 volts.... All the best.

Results of the battery endurance test. No surprises here, I've used the battery enough to know that a full charge will see you to 4 hours. From 21.5 volts to 16 volts is 4 hours. Today I used the speaker and started at a lower voltage, just over three hours and twenty minutes runtime. The PCB will cut the power at 16 volts so you cannot overly discharge the cells. No warning the machine just turns OFF. That is a good thing. Started at 19.53 volts, an hour later 18.47 volts. An hour later 17.74 volts , an hour later 16.76 volts and twenty minutes later it cut out at 15.97 volts. Three hours and twenty minutes, use a set of headphones and you will get extra runtime. Ok maybe I need three battery packs for a full days detecting...? All for now, all the best.

Now that White's is gone, pays to nurse the machines. I keep the SL machines well under 16 volts, just peace of mind. My standard Tdi Pro had standard battery packs that are 16.8 volts hot off the charger, no problems there. The modified Tdi Pro is the machine that gets the hotter 5 x 18650 battery pack, in for a penny in for a pound.. Hot off the charger it has 21.5 volts if I let it. I use a timer and try and keep it at 20 volts max or just a bit under. Just started a discharge experiment, battery was in the machine for a month after being charged to 20 volts. Starting voltage was 19.53 and I'll check it every hour after that to see how much run time if provides. I am looking to go down to roughly 3.2 volts per cell or 16 volts for the pack. So maximum charge of 20 volts and maximum discharge to 16 volts. We have to draw our lines somewhere. That leave run times. I'll have the answer to that shortly. Ok so after one hour or run time starting at 19.53 volts it is down to 18.47 volts. . no outward signs of heat issues. Removed battery and checked the machine for warm spots etc. Have used this setup on the beach for many hours and the Tdi Pro seems to work without any issues at the higher voltages. Long term wear or strain on components is another issue, so far so good.

Just finished my second attempt at the heat shrink wrap. This time I used a hair dryer, perfect for this material. Stay away from flame lighters etc. Just wanted it simple and tidy. Perfect fit no issues. Kept the battery in the machine for over a month, naughty but I wanted to check for parasitic drain. None found. Next job was to run the machine until the battery was run down and then recharge. Then repeat a few times.. Again so far no issues found. Setup seems to work well. The heat shrink wrap was new to me, once I worked out that a hair dryer is best I was comfortable with the material and should only improve my technique. Important since I will be refurbishing older factory packs with new cells in the near future. Again giving the Tdi Pro a boost and longer service life. The issue of older battery packs is now much less of an issue for me since the idea of refurbishing them seems less of a challenge. We learn as we go along. Once I've fully tested the 5 x 18650 battery pack I'll consider making a second one since I've got enough spare parts and cells for the project. Two upgraded battery packs will provide the Tdi Pro modified unit with enough power for a full days detecting. So far so good, next step is to give her a good run out in the goldfields. All the best.

Sorry for the delay, it's been a distracting year or so. Will complete testing the Tdi Pro modified with the upgraded battery, as soon as it stops raining... in the goldfields with targets in the ground. I'll include the parts list etc. The modified pro with that 18 x 6 mono coil has performed very well on the beach, punches deep and covers lots of ground. The modified unit is going soon but I'm keeping the standard machine. Apparently 'she who must be obeyed' just noticed there are two Tdi Pro machines and is on the warpath.. I just need to give it a final run on the goldfields. Some testing and opinions to follow shortly. Rain permitting.. All the best. Karelian

GeoBill I have not turned the machine back into a Tdi Sl, just yet. Have been 'playing' with it as a SPP. I'll put the PCB back and attempt the adjustment just to see if that is the fix. If the fix works I'll keep it as the SL, but keep the spare SPP PCB for a rainy day.. Sorry for the slow response.