Surf Pi Professional Pcb's back in stock - NEW Prices

[satdaveuk]

Best wire to make a Surf PI coil is wire from CAT.6 UTP Network Cable (24 AWG Stranded)

You can buy 100 ft. CAT.6 UTP Network Cable on eBay for $12-$16
then remove wires from the cable and untwist twisted pairs.

You will have 8 pieces of 24 AWG wire 100 ft. each.

1. 24 AWG is an original wire size for Surf PI (0.51 mm)

2. Stranded wire will reduce eddy currents inside the wire and make your coil "fast".

3. PVC insulation will reduce coil capacitance make your coil "fast" and improve insulation of high voltage impulses.

4. PVC insulation in network cables is relatively thin so your coil will not be too bulky.

5. Saving money is OUTSTANDING !!! For $16 you will have 8 pieces of 24 AWG wire 100 ft. each.
Usually you need 55-60 ft. of wire to make 1 coil. So you can make 8 coils (and spend $2 per coil)

WARNING: Always check what you want to buy. Many China companies stealing cooper from cables
and using thin wires instead of AWG 24 even if you can see it marked as AWG 24.
To be sure that wires are good do not buy cheapest cables, ask seller about quality.
Also you can check resistance of the cable. It has to be 2.6 Ohm for 100 ft.
weight of 100 ft. Cat.6 network cable with proper wires is approx. 2.6 pounds because cooper is heavy. Light weght cables are fake.

Once I have purchased fake Cat.5 cable for $8 on eBay. (LEFT ON PICTURE)
Wires were approx. AWG 31 instead of AWG 24 and even not twisted pairs. resistance was 21 Ohm. Avoid to buy such fake.

Link-depot CAT.6 cable I have purchased for $16 was ABCOLUTELLY PERFECT (right on picture)
http://www.ebay.com/itm/120872033740

That looks like 8 core alarm cable on the left about third of the price if not less

[Waikiki_Sweep]

Best wire to make a Surf PI coil is wire from CAT.6 UTP Network Cable (24 AWG Stranded)

Best wire to make a Surf PI coil is wire from CAT.6 UTP Network Cable (24 AWG Stranded)

You can buy 100 ft. CAT.6 UTP Network Cable on eBay for $12-$16
then remove wires from the cable and untwist twisted pairs.

You will have 8 pieces of 24 AWG wire 100 ft. each.

1. 24 AWG is an original wire size for Surf PI (0.51 mm)

2. Stranded wire will reduce eddy currents inside the wire and make your coil "fast".

3. PVC insulation will reduce coil capacitance make your coil "fast" and improve insulation of high voltage impulses.

4. PVC insulation in network cables is relatively thin so your coil will not be too bulky.

5. Saving money is OUTSTANDING !!! For $16 you will have 8 pieces of 24 AWG wire 100 ft. each.
Usually you need 55-60 ft. of wire to make 1 coil. So you can make 8 coils (and spend $2 per coil)

WARNING: Always check what you want to buy. Many China companies stealing cooper from cables
and using thin wires instead of AWG 24 even if you can see it marked as AWG 24.
To be sure that wires are good do not buy cheapest cables, ask seller about quality.
Also you can check resistance of the cable. It has to be 2.6 Ohm for 100 ft.
weight of 100 ft. Cat.6 network cable with proper wires is approx. 2.6 pounds because cooper is heavy. Light weght cables are fake.

Once I have purchased fake Cat.5 cable for $8 on eBay. (LEFT ON PICTURE)
Wires were approx. AWG 31 instead of AWG 24 and even not twisted pairs. resistance was 21 Ohm. Avoid to buy such fake.

Link-depot CAT.6 cable I have purchased for $16 was ABCOLUTELLY PERFECT (right on picture)

http://www.ebay.com/itm/120872033740

[Waikiki_Sweep]

I have noticed SIGNIFICANT difference in resistors and capasitors values in the new version

Dear ApBerg,

On your photo (post #196) I can see a part of new Surf PI schematic.

I have noticed SIGNIFICANT difference in resistors and capacitors values
between the old version of Surf PI (Longboard) and this new version.
As I can see new version has to be much more sensitive.

R22 old version 100K new version 220K --- Gain increase
C6 old version 100n new version 47n --- to keep the same time constant
R20 old version 22K new version 47K --- Gain increase

Also on layout in your post #188 I can see different values RC for integrator
C5,R15,C6,R16 changed from 220K, 470N to 330K, 330N to increase Gain
but no such changes on last photo (post #196).

Can you please let us see whole schematic of this new version.

I think Longboard owners can just upgrade their detectors to new version by changing
some resistors and capacitors and adding sensitivity pot.
I would like to upgrade my detectors too.

Probably Silverdog can upgrade his Longboard kits for this new more sensitive version
without actually changing layout.

NEW AND OLD SCHEMATICS. COMPARE IT:

[Davor]

I think the Barracuda is the better DIY project...!

Now that you are stirring some strange waters, would you care to elaborate this conclusion in a few more words?

[UFO]

I think the Barracuda is the better DIY project...!

That's good to hear. I'm waiting for a couple Barracudas to arrive to build for another forum member and myself.

[ApBerg]

UFO:
Actually the longboard is cool for putting into tubes etc, but I was surprised that there was not the regular shaped board as well.



... made some 'normal' board in Sprint Layout ...the last after Carl gave the Whites Surf Pro schematic on this board.

Have not made it for real, only as pcb Sprint file, so there can be errors in it !! The potentiometers can work inverse.. there is a extra potentiometer near the 555 and a extra preset delay

If somebody can check it.. ?

Best regards

Ap

Made 2 different layouts from the Surf PiPro, not bad detectors...
In the SprintLayout JPG the pins 4093 8/9 chanced place ! ( post no. 188 ) Not ok. but the detector worked !?

I think the Barracuda is the better DIY project...!

[sparky]

Thank you! Very nicely done.

I will be starting on mine very shortly.

[Waikiki_Sweep]

more details

Can you give us more details on your detector. How many turns and what gauge wire did you use on coils? What is your coil assembly made of? How did you make the headphones waterproof? How did you waterproof the headphone wires going into the box?

Wire: AWG 24 or AWG 26, Teflon or PVC insulated, stranded.

Turns: 18 or 20 or 22 (18 for bigger coils, 22 for smaller coils) Everything will work
from 240 mH to 350 mH inductance, just need proper dumping resistor.

Coil assembly: coil covered by several layers of fiberglass, just like surfboard but no air or foam inside.

Headphones waterproofing: I have purchased mylar blanket from WalMart and Aluminum Foil Tape for waterproofing appliances. Aluminum Foil Tape looks like scotch roll, it is sticky and smells like gasoline or patches for bicycle tires.
I put speaker on mylar film face down then cover it with piece of Aluminum Foil Tape (put a few drops of sealant on wires to stop water going along speaker wires) Aluminum Foil Tape will stick to mylar to seal the speaker. You will have an envelope with one side mylar (front of speaker) and another side - Aluminum Foil Tape (back of speaker). May be it is good idea to paint Aluminum Foil Tape side to prevent corrosion. Keep mylar metalized side inside or water will corrode aluminum from mylar film. Use ohmmeter to check what side of mylar is metalized. Insulate connection points on the speaker from Aluminum Foil Tape or it will short the speaker. I am using Hot Glue to seal wires where two speakers connected together and spiral phone extension cord.

Waterproof cables: I am using big amount of Hot Glue to seal cables coming to the box inside and outside.

To make a stem I have bend PVC plastic pipe by heating it on gas burner.

I have checked that Surf PI is very stable if properly assembled so you do not need any pots outside just Turn ON/OFF switch and adjusted once it will work for years with the same settings.

Aluminum Foil Tape:

[sparky]

Can you give us more details on your detector. How many turns and what gauge wire did you use on coils? What is your coil assembly made of? How did you make the headphones waterproof? How did you waterproof the headphone wires going into the box?

[Waikiki_Sweep]

Li-Ion 18650 rechargeable batteries 3.7V should be a STANDART for 12V power supply for MD

3 cells of 18650 3.7V rechargeable batteries In full charge will give 4.18V each or 12.54V.
Also it has approx 2200 mA/h capacity that is close to regular alkaline AA.
Some new 18650 advertised to have 3800 mA/h or more.

3 cells of 18650 takes much less space and weight much less then 8 AA pack.
Also it costs you nothing because you can charge it 500 times and have LIMITLESS
source of it from broken laptop computers. Or you can just buy such cells for $2-3
on eBay.

Chargers are cheap too: http://www.ebay.com/sch/i.html?_nkw=18650
I have purchased two for $3.40 each. Last year I have assembled my own charger
with using MAX1555 IC. But chargers from China looks cheaper and easier to buy.

You will need to buy a proper case that fits your design:

http://www.ebay.com/sch/i.html?_nkw=18650+case

Regarding how long it will work with Surf PI.

As I know Surf PI is using 55 mA current. So it have to work 20-40 hours on one charge
just like regular 8 AA batteries pack before you will need to recharge it.

BUT !!! Once you noticed that now you have endless source of FREE power you will
start experimenting. No reason to care how much power suck your metal detector.

So first what I did I have increased impulse width.
In regular Surf PI you can see that 25 mA consumed by schematics and 25mA goes to
impulse magnetic field. (If you disconnect coil you will see only 25mA consuming by schematic)

In my two detectors I have 85 and 120 mA power consumption because of longer
pulses. So 60 and 95 mA goes to create much stronger magnetic fields.

2-3 times stronger magnetic field lets me to seek for dipper targets and
excite smaller targets too like small gold. (To prove it i can show gold chain 6mm wide i found)

It is not a my invention. You can read manual for Tesoro Sand Shark metal detector.
They state that longer impulse consuming more power but may increase sensitivity:

http://www.kellycodetectors.com/pdf/manuals/tesoro-sandshark.pdf

Also I think that impulses in Whites Surf PI PRO Dualfield are more powerful too
because I can hear interferance from Dualfield detectors from much far distance than
from older Surf PI on my beach.

So I am recharging batteries from one detector (120 mA) after 12 hours of work and
for second MD (85 mA) after 20 hours. Or i can charge it daily to have top voltage all the time.

With more power you can use bigger cois to cover more area and bigger wires to supply more current.
You can rise frequency to have more readings per second.
So no more limited and expensive power from AA batteries.

With Li-Ion cells you will have wide field for overclocking experiments.

Also you will GO GREEN !!! I had boxes with pounds of partially used AA batteries
before switching to Li-Ion.

[juice2839]

Laptop batteries

I noticed you used Lithion laptop batterys. I was thinking of doing this exact thing. How much time do you get with your detector with these fully charged?

[Waikiki_Sweep]

My MD's in SNAP SIGHTS UNDERWATER film camera cases

Thank you so much ApBerg for Layout update!
I will try to check this layout. I hope to see it "in production" some day.

Did you named this version yet? :-) Longboard is a famous brand this one will be too.

Also I can see Sensitivity pot in this layout.
It looks important and makes it superior to Longboard.
I have checked that Surf PI in air can work with 4 times more amplification
than in salt water. So we can adjust sensitivity when use it in land or water.

Below I am glad to present my MD's in SNAP SIGHTS UNDERWATER film camera cases I am using from 2009.

First MD has been assembled even without PCB. I have used Radioshak Prototyping board.
I second MD I'v cut Longboard in two pieces.

[smity]

Dear Appie. I really like your printed circuit boards. But the long PCBs, the best among the best! They are very convenient for use under water. You do such a variant for "Pro" version? Yours.

[ApBerg]

UFO:
Actually the longboard is cool for putting into tubes etc, but I was surprised that there was not the regular shaped board as well.



... made some 'normal' board in Sprint Layout ...the last after Carl gave the Whites Surf Pro schematic on this board.

Have not made it for real, only as pcb Sprint file, so there can be errors in it !! The potentiometers can work inverse.. there is a extra potentiometer near the 555 and a extra preset delay

If somebody can check it.. ?

Best regards

Ap

[UFO]

Lol that's funny I thought of doing the same thing.

Actually the longboard is cool for putting into tubes etc, but I was surprised that there was not the regular shaped board as well.

I picked up one of these waterproof boxes from Walmart that I plan on using for a MD project. The inside dimensions are approx 130mm x 80mm.

If you look in the second picture you will see there is a small vent to release the pressure when you open it. I prefer that it was not there but I guess it's not the end of the world, just make sure it's clean when you snap it shut. It even came with a spare rubber plug which I might have misplaced already. (I put it in a spot where I would not lose it.)

They also have larger sizes.

This one weighs approx 230 grams, without the red liners.