IDX-PRO+VDI

[golfnut]

Hi, yes Barry, making one in a scratch cover is do able the hard bit is getting the mountiong lugs/ears done . I did a write up on here somewhere I made a concentric whith a whites 8 or 9" - quite thick plastic actually - rigid.

Ive casted one in glass fibre and resin on a plastic camping plate one time, Ive made small monos on a kids table tennins bat - and pulled roman coins with it! Would not recommend - fiddly and heavy

Georgi on here does a black 27cm DD shell and they are OK. - but often to get free post you have to buy 10 I think - check his terms in buy/sell section..


There was a web shop in eatern europe the does shell too. .... here

http://crazy-tech.net/index.php?rout...&product_id=53

I have one of these in white if your interested - they are a touch heavy when potted as the central area is voluminous... I tack in loads of closed cell foam blocks and offcuts to reduce mass. Also the cable entry is right on the centre of these and looks a tad odd to me..

The same site does an elongated DD type which Is in two bits a bottom plate with a lip and top half - which is more akin to regular shell. If you used this, you may be able to pop it open again and re mod if not happy with performance - just a thought, Bit like a teknetiks shape ... http://www.tekneticst2.com/

[golfnut]

A few coils and shells for ideas

[dfbowers]

What has your experience been with the "butterfly" coils? I haven't tried making one of those yet.
All kinds of things to consider when building. Pin pointing, ground coverage, ground signal cancellation, EMF cancellation, depth, maneuverability,
weight, buoyancy, target separation. All coil geometries have their merits!
Don.

[golfnut]

Your right Don 2 bits of required info are, what do you want to hunt and what are the conditions like.

I was using a 27 DD and it was fine - general purpose. At 12khz Tx 8khx Rx - to see smaller items.


The butterfly is not a depth beast, its use is ground coverage in record time... - mine is 13"? long but only 8 wide.

I wanted to cover a little more ground per unit time, I went for a NEL Hunter ~ Not the deepest- but handles europe clean soil well. This also doesnt like wet grass.
I got a high frequency version designed for a Tejon. It has no caps in the coil so you need Tx and Rx cap in box.
I messed about with the cap values to give me phasing / some depth and a usable null. 12k Tx - I pull small silver to 6" reliably with it - the photo earlier of roman and medieval was from this NEL. Its cable has 2 coaxes. in shotgun, one fro Tx and one for Rx.

The depth is about 90% of the smaller dimension, from experience.

Lots of uk guys put a dual ellipse / butterfly on a 250 and do real well relatively. ~As the original 250 coil is a bit lame.

I have a modified 250 that takes my nel hunter and runs 15,5k Tx - needs some work though.


The Deus lads rape it, they all have bad knees, as theyre always on them digging finds while spectrum and rapierII owners wander aimlessly.

Steve

[hoadlies]

THANKS,STEVE ,,for the Pics ,nice to see the empty shells for idea/s & links to Shells..

I will get something organized soon..

CHEERS,,, BARRY..

[golfnut]

Hi Barry I got a pcb through from andy but it was an older one with a short I don't think I made myself clear, I will contact him again. S

[Schatztaucher]

Hi guys,

can someone tell me how important the diameter of the cable for the switches, potentiometers, etc are? and if so, what should you take?

regards, marc

[Koala]

Hi guys,

can someone tell me how important the diameter of the cable for the switches, potentiometers, etc are? and if so, what should you take?

regards, marc

Not important.

You do have to be careful of noise though. Twist wires together seem to work well. Keep them as short as possible. Metal POT's are best and ground them together with the coil connector shell. Not vital but the detector will run much smoother. Testing is also much more consistent.

Don't worry to much does not make that much difference. Ran mine grounded and not grounded twisted not twisted on the bench the only one that made much difference was the grounding of the coil connector.

I used a metal box and the outer edge of the silverdog PCB as ground which is not a true ground. This means I have to insulate the headphone jack.

[hoadlies]

HI ALL ,, WELL The kit fired up 1st time, I connected it to my coils [unscreened & not nulled as yet] but I did get some signal ..
I have a lot to learn on the various control-pot settings ..
I should screen[Faraday] the coils & do the Nulling ???.. & then continyou with further testing etc..

A question reguarding the USB2 cable I have selected the one [from 2 differing types] that the screen will solder as some seem to be stainless??? & do not tin.. any way my query is the USB-2 has 4 cables ,2x cables are red& black the heavier cable & then 2x lighter ones ..''Which would be best to use on TX '' & or RX .???.. I have the Heavier cable on RX at present ..

Secondly I notice touching pots [touchy] Should I ground the Pot bodies To the ground surrounding the board [as described above],I thought when finished I would use a plastic tupperware box lined with alluminium shield tape ??? I could buy a project metal box but I do not have a good size one here ..

I am pleased with the initial power-up & I Thank all those that have helped me get this far with my 1st build ..

OK,,,,,,, STEVE ,,,,,,,,,, A dedicated Schem for this latest board will be a great help to us all so,, Thamks for perservering to get it done ..As its a bit confusing seeing the various schems & boards ..[for a Newbie especially]..


CHEERS TO ALL,,,,,,,,,,,,BARRY..

[Schatztaucher]

Thanks Koala!

[Silver Dollar]

On my USB cables I noticed the same thing the shield wouldn't solder then I found a tiny drain wire made out
of copper that sits inside the stainless mesh. So I cut away the stainless and only used the tiny copper wire.

I had to ground the shells of the pots too to keep them stable. Thew ground balance is especially sensitive...

[hoadlies]

On my USB cables I noticed the same thing the shield wouldn't solder then I found a tiny drain wire made out
of copper that sits inside the stainless mesh. So I cut away the stainless and only used the tiny copper wire.


I had to ground the shells of the pots too to keep them stable. Thew ground balance is especially sensitive...

YES S/D,, I had that in mind as well slipping in a bare copper wire ,But as I wrecked 3x USB-2-Cables One of them had solderable screen as well as the Alluminium screen ,,ALL have the same 4x wire specs as to guage the Red& black's are heavier, than the other 2..
well-Mate its certainly a learning proccess HA.Haar ..

I, will balance the DD coil ,next & try testing again..

CHEERS TO you MATE iS it still Cold over there ???BARRY..

[Silver Dollar]

Well today it is 20F (-7C) and we just ran out of propane for our furnace!...

[golfnut]

Hi Barry, I would use the red black for Tx -- also Id say solder the drain wire of the cable as the foil is all and of course does not take solder.

If you send a pm with your email in I will send you an interactive schematic with scope traces on the test points S

[hoadlies]

Well today it is 20F (-7C) and we just ran out of propane for our furnace!...

WOW,, Thats Bl**%#y cold mate

Brass-monkey Cold..

Do you have large propane Cyl & or Bottles ..
I use LPG in my Car & the price at present is really high @ $1.00 per litre..[some world paraday pricing excuse] ..
Unleaded petrol [Gas] is $1.50 per litre ..
Getting too expensive to travell places..

CHEERS MATE ,,Stay-warm ,RUG-UP,,BARRY..