Stop building PI detectors!

[Nupi]

i guess FF do not know that russian one had released PI-VLF-all-in-one detector two years ago. hybrid? i do not know, this named 'universal'.
its frequencies range --- 4-12kHz (IB), 400Hz (PI)

I suppose you get a real free bottle of vodka with the detector.

http://i67.tinypic.com/6olijl.jpg

[Nupi]

I do offer Mirage PCB and component parts kit, have made about 10 u/w units over the past few years. Guys love them for saltwater beach and surf hunting.
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Just had a new batch of PCB's made. PM me if you want pricing and more info.

But, you can also make a water PI from the Barracuda, Mini-pulse, Surfmaster etc.

Looks very good.

[Nupi]

@kt315
Is that your dog ???

[kt315]

what you know about digging nupi. NOTHING.

[kt315]

[Funfinder]

The issue is that this forum suggests that building PIs would be
the best choice because 90-95% here is just about PI-projects.

Comparable as if some BFO-fan creates a forum where everyone just builts those
circuits and which gives the impression this would be "state of the art"-technology.

Under special circumstances a PI rules out all other detectors might be right and
is also Minelabs philosophy but when do occure such conditions?

Searching for natural gold at black sand or red hot rocks without any other metal
objects because that way the contrast gold vs. ground-mineralization is pretty good.
Of course very slowly because the PI doesn't likes it fast and its weight also adds.

But even if let beside the fact that a good non-motion-detector will do the same good
job under such conditions or even better because of higher speed and better discrimination
and that the market prefers to sell motion-detectors which are not good for such search-tasks:


How can anyone assume here that all people who wants to built some detector, will search
for natural gold ??? Perhaps around 20% might wants to search for nuggets in Australia
or other places which are rather rare, BUT the rests wants to have a fast and deep detector
with good discrimination!

And perhaps 5% wants to built a PI with really huge coil so they can dig big holes as we
see above from kt315 posted - and so they can save their money for expensive but
professional non-motion detectors with 1m coil like the Jeohunter or DeepHunter.

Apropos professional:
Minelab also wants to be as professional as possible with its Aussie-gold-nuggets-detectors
and people who find enough nuggets won't care about the price, but MOST treasure-hunters
can live easily and very happy without those overpriced and heavy PI-detectors!

And the same way most treasure-hunters would prefer here in this forum a realistic relation
concerning DIY-detectors to built which fits much better their needs as almost P.I. only !!!

I don't care about the ratio PI : VLF projects here, but it should be much more realistic.
And not almost 100 against Zero!
This way you also will earn more respect from those who are really missing up-to-date
and semi-professional VLF or IB selfbuilt-enthusiasm here.

btw. Of course you can't detect an airplane with a metal-detector but with radar-technology
and homebrewers ("moonshine-detector"-builders ) have a very fast success experience
when they do some in-air-tests with their fast and simple creatable PI-builts, but for PI this is very
deceiving compared with real in-ground-tests and if the PI-user finds out that its no fun being fixed
to all-metall-search every time! So please be fair and offer here at least ONE modern VLF project
so everyone has the choice between PI and IB. Modern means that it comes with good depth,
ground balance, discrimination and capable of different coil-sizes - not too complicated to built.
This even can be some non-motion detector for max. depth and cavity detection or some 2in1 -
motion plus non-motion in 1 - switchable for all purposes!


So finally we have here at least some 5:1 DIY-threads ratio PI versus VLF and not 10:0 !!!

[SVEN1]

I think the forum then needs a VLF detector as you describe but, it has to be a guaranteed working project. If a person buys the PCB adds the correct parts in the correct spaces, has a coil made exactly to specs and completes it right to specs as intended it should work. What turns new builders off are projects with schematic errors, PCB errors, parts value errors changes which create problems for most. Then everyone chimes in with a fix for this a fix for that, some work for some won't work for others. Eventually the builders get sick and tired monkeying around trying to get a project to work and it gets tossed in a junk box. I have tried many Geotech projects and failed because of errors, parts changes as described above. Only one project functioned as intended the Surfmaster. All the VLF projects I have tried failed to work or work properly. I am giving the Magnum on Steroids one last shot. Give the novice, beginner a chance and feel the pride of building a working project.

You have to wonder how many novice, beginners join Geotech with high hopes of building their own detector and finding treasure with it. How many of these members never post and or give up a project here in disgust and never come back?
If a novice beginner does complete an excellent working project, they are more likely to advance onto another project. Maybe some day even offer a project of their own to Geotech.

Once a builder has working project, then the accomplished happy builder can go onto modifying or improving the project.............................

There should be first time project to advance from. Since a mono coil is easy to build, then a PI will be the easiest to build and understand. Think George is trying hard with his Mini-Pulse Plus.
For a VLF project, there should be a ready made coil or coils known to work with the project, that builders can buy. DD coils are not easy for many or many don't have the capabilities to build one.
Unless they can buy one, a VLF project may not be viable.

Just a final thought, had it not been for the Mirage PI, not a Geotech project, which started off as a working bread board build, I would have given up trying to build a detector or still be a member of Geotech.
Because of the difficulties building projects here, I made sure when I was positively happy with the build, then I offered it to others. Geared all the building steps to the beginner in terms they could understand.
For the most part, if they soldered the right parts to the right pads that were marked with parts values without solder shorts, bridges, then built a simple mono coil, calibrated as instructed, it would work. And
Mirage performance most builders were thrilled about. A gold nugget and gold jewelery mainly and coins secondary. It works rather well in trashy areas. Still goes deep enough for most relic hunters in the US-Canada
with the 10.5" coil. If built as instructed, it will work. Those that think they can tinker with the circuit or experiment before first building a working unit, seem to be the ones that develop problems. Finding many of the
novice builders can easily build a working unit....funny how those so called claimed electronic techs engineers, who should not have any building problems, run into all sorts of problems.......some are so elementary that should not even be an issue.

These are just my thoughts about projects here, starting as a beginner-novice myself a number of years ago. By all means I am far from a electronics expert, engineer like many here...Still a self taught electronics beginner but, an expert builder that can tackle most projects.

Over the years, I have talked to many many detectorists that would love to build their own detector. Some have only solder skills others in the past bought simple electronic kits when younger and have a desire to build a detector. A good PI project with good performance, I think is a good start even if this type of person, even if they would prefer a VLF build. Start them someplace. I think George's Mini-Pulse Plus is headed in the right direction and has plenty of room for advancement in performance. Generally this is the PI I suggest as a first time Geotech project......build as George instructs.....

As I mentioned the Mag. on Steriods will be my last Geotech VLF project, working slowly on it, will keep a log on what works. Hopefully one day it can be an easy build for many that will work. Keeping my fingers crossed.

[Dave J.]

The advantage of PI as a DIY project is that most PI designs will run darn near anything as a searchcoil.
VLF requires an induction balance searchcoil. Easy in principle, difficult in practice. The solution to this problem is obvious: design the thing around a widely available commercial searchcoil.
Either a PI or VLF can be as (relatively) simple or complex as you like, but of course higher performance and more features mean a more difficult project.

When you've built a PI, what you have is a PI. They have their good points and their bad points.
When you've built a VLF, what you have is a VLF. They have their good points and their bad points.
Neither technology obsoletes the other.

[dbanner]

In my experience, good for wet sand at the beach. For less than 100 dollars you can do a barracuda clone. Sure there's no disc. but have you seen the price of tesoro tiger shark or the excal. Pi detector are easy to set up as well. Monocoil and damping resistor is all you need. A VLF motion machine will require very good shielding as well if you're going in the water. So start with a homemade pi at the beach like surf pi or barra, find as many rings as you can, then sell them, then upgrade to a factory built VLF like the tiger shark. Its about the economics as well.

[Hyena]

In my experience, good for wet sand at the beach. For less than 100 dollars you can do a barracuda clone. Sure there's no disc. but have you seen the price of tesoro tiger shark or the excal. Pi detector are easy to set up as well. Monocoil and damping resistor is all you need. A VLF motion machine will require very good shielding as well if you're going in the water. So start with a homemade pi at the beach like surf pi or barra, find as many rings as you can, then sell them, then upgrade to a factory built VLF like the tiger shark. Its about the economics as well.

Also this is not for anybody. Here in central europe we have hundreds of rusty nails, tens of bottle caps, chains and horseshoes in every hectare. Not a single beach - if you want to detect in water, you should visit some river. For less than 150€ (thanks to cheap chinese comrades) I made two TGSLs. Now for similar price I am working on two IGSLs and I started to build Magnum on steroids (I have kid now, so less time to this hobby). In 2015 and in past a made few electronic kits (and one toy-BFO-detector ). In 2016 I learned more than in my entire life thanks to (not only) TGSL thread and my worst enemy - who inserts lots of mistakes into my projects - Me

If you just want cheap and simple machine and go out soon - make simple PI.
If you want to learn something about electronics and not to dig every needle - make VLF. Like Dave Jones said - If you want to learn something about electronics design, I hope your next project will fail from the beggining

Come on, that coil is not impossible to make. You can make it and null it (with 2 channel oscope) in matter of hours. Concentric is even more simple - I dont know why it is so often labeled as more difficult than double D.

[scrungy_doolittle]

ROTFLMRO! Nice Carl.
All detectors have their place...
BFO's would make good pinpointers...

[scrungy_doolittle]

PI detectors are inherently easier to build than IB detectors, which is why you have so many PI designs floating around. I don't do beaches or hunt for gold, so a PI is limited value for me, but one day I want
to add one to my arsenal of detectors. Simply because.

[satdaveuk]

Yep. Found my first Silver quarter with a BFO ten minutes after putting batteries in the thing. They Still have a Place. Year ? 1972.....

Blast from the past
That very same year whilst still at school I built my first Metal Detector

[Teleno]

f you just want cheap and simple machine and go out soon - make simple PI.

If you want depth get a PI.

[c_batchelar]

for me i like pi because its hard to swing a detector at all in the areas i hunt in it all native nz bush
http://www.doc.govt.nz/nature/habitats/forests/
so a slowswing through furns and around trees is were im at