Bandido II coils and other stuff

[Qiaozhi]

This diagram should also be correct for my deleon coil?

I don't know the answer to your question. Have you checked the inductance of the coils according to the diagram? Even a simple connectivity check with a multimeter can be used to determine if the connections are the same.

[Max]

Greetings,

Mentioned earlier was something about teflon wire, and what seemed some trouble obtaining. could go to your local automotive engine rebuilders store, find some tef-coat or similar, empty into cooking pot place on electric stove heat and boil your coil of wire. The copper will expand and teflon will bond to it. (just like cooking projies).

About coils, have/ has anyone tried the one or two coils (depending on model and size) located in the back of TV sets.?

And the following design coil might be something to play around with if interested.



Regards

Hi,
you can find teflon insulated copper wire already made. It's not cheapy but you don't need big volumes e.g. to make a PI coil. Teflon wire is not good for VLF coils cause you need much more inductance and so more turns, that will not suit in any case if wire is too thick.
For PI coils teflon covered wire is the best out there cause gives very low capacitance to the coil itself, so aid to reduce minimum sampling time to less than 10us (if other stuff is ok too).
TV-CRT coils are not good for VLF cause inductances are too low and shape has different role than in metal detectors(deflecting moving electrons).

Best regards,
Max

[asguard]

Greetings,

Mentioned earlier was something about teflon wire, and what seemed some trouble obtaining. could go to your local automotive engine rebuilders store, find some tef-coat or similar, empty into cooking pot place on electric stove heat and boil your coil of wire. The copper will expand and teflon will bond to it. (just like cooking projies).

About coils, have/ has anyone tried the one or two coils (depending on model and size) located in the back of TV sets.?

And the following design coil might be something to play around with if interested.



Regards

[sa1ka]

this should also be correct for Deleon?

The coil connection details are incorrect. In fact, the last diagram is one that I created while trying to debug a faulty Tesoro Laser.

Here's the correct wiring:

This diagram should also be correct for my deleon coil?

[Lev-HUN]

Hi!

I've seen MAX's BanditoII project. I think I'm gonna try to build myself
one 'cause The BanditoII with the large 10*12 coil was very well rated
in the Big Detector Test in Belgium.
If anyone has any data or description of the 10*12 coil, please send to
me or link to the forum.
Is there any special info I need to know to make a coil that almost as
good as the manufactured one.

Thanks:
Levente

[chemelec]

All the Info is Now Posted here:
Including a Revised Schematic.
(This Print Nicely on an 8.5 by 14 Paper)

http://www3.telus.net/chemelec/Projects/Bandido-Split/

All Future Updates to this Will be Posted in the Bandido Section at the bottom of Geotech's main page

[Max]

Here are the PCB Layouts and some pictures.
More to come.

http://www3.telus.net/chemelec/Projects/Bandido-Split/

Hi Gary,
as always very good work!
Thanks.

Max

[chemelec]

Here are the PCB Layouts and some pictures.
More to come.

http://www3.telus.net/chemelec/Projects/Bandido-Split/

[chemelec]

Just an Update on my progress:

As I Said, It was working good, but one board had a few small errors that I temporary just fixed.

I have now Revised these "Split Bandido PCB's", to properly correct them.
I Also Re-Made the one board that had the small Errors and have re-assembled and re-tested it.

I Will Post the PCB's later today, along with Pictures of the two Assembled PCB's.

I still have some work to do to revise the schematic.
Hopefully I will get that completed this coming week.

This unit uses the MC7660 for the Negative Supply and it delivers a "Negative 4.5 volts". The Positive is still Plus 5 volts.

The board also Incorporates a 2 LED Battery Indicator.
(Good or Low battery Indication)
I think its useful, but you can Either Add these components or Leave them off.

Take care....Gary

[Max]

As to getting Wire, Besides MARS, Where do you Really Live?
Email Me.
Definately Notv Practical for a8 Pound Spool, But maybe I could do something for you.

Yes, Teflon is good for PI Coils.

**Bbsailor sent me some samples to do some coils for Comparative Testing to my coils. (VERY NICE OF HIM)
They did work slightly better, but at the Price of the Teflon wire, I don't think the Results were worth it. At least Not for My applications

Take care...Gary

Hi Gary,
Done. I found teflon is very good for PI...I've realized different ones (stuart, gs4...etc some by protoboards and others with true PCB; I have 2 stuart now...with small differences...and close performances too). A good GS4 proto also that works good but:
my real problem with PI are ceramic fragments...so I've realized I need a good disc unit...easy to use, and Reg suggest "Bandido"!
So, now I'm dealing with bandido to avoid ceramic interference, in some search fields, that are very boring and also too-digging-addicted.
I use PI when I do beach searching, but not really interested in beach searching.

I've used VLF's before but sometimes they were too low sensitive. Hoping that Bandido isn't like these old I've used in past years. Anyone talk good things about tesoro and bandido expecially but I never had one...can't say before field tests - also some older vlf sounded loud with ceramics !.

Best regards,
Max

[chemelec]

Hi Gary,
wow 25,000 feet at very good price ! I'd like to buy a roll...but unfortunately for me
I think it's not so cheap to move 8pound of stuff around the globe...don't know how much
can it costs by DHL,FEDEX or something else.

"I really doubt that Teflon wire would make that big of a difference on this coil.
And to get the Required Inductance, your going to need a Lot More Turns."

I've read the bbsailor article on fast monocoils for PI. So I've tested some teflon insulated
0.37mm diameter wire (a special wire for "hot" devices) and worked very well.
I've breaked the 8uS barrier that is very very good for me!
Yes, it's thicker than enamelled and not suitable for VLF kind of coils. But for PI is ok.

I have kilometers of old litz... very good quality but too thin for most applications.
It was used in crystal circuits...and radio in general...
I think it could stay in a museum ! (seems it was made in 40's, don't know for sure!)

Today it's not so used as in the past. Not so thin at least.

Best regards,
Max

As to getting Wire, Besides MARS, Where do you Really Live?
Email Me.
Definately Notv Practical for a8 Pound Spool, But maybe I could do something for you.

Yes, Teflon is good for PI Coils.

**Bbsailor sent me some samples to do some coils for Comparative Testing to my coils. (VERY NICE OF HIM)
They did work slightly better, but at the Price of the Teflon wire, I don't think the Results were worth it. At least Not for My applications

Take care...Gary

[Max]

My Wire Supplier is also Quite far away from me, but about 3 times a year I drive 4 hour, Each way to get more from him in Vancouver.
I Usually make it a 3 day trip and buy other stuff as well. But He doesn't have much Teflon wire and I don't really use it much either.

I use Litz wire sometimes, but I usually make my own.

I really doubt that Teflon wire would make that big of a difference on this coil. And to get the Required Inductance, your going to need a Lot More Turns.

By the way, an 8 Pound spool of 30AWG Enamel wire is about 25,000 Feet. One roll Keeps me going for a little while.

Take care.....Gary

Hi Gary,
wow 25,000 feet at very good price ! I'd like to buy a roll...but unfortunately for me
I think it's not so cheap to move 8pound of stuff around the globe...don't know how much
can it costs by DHL,FEDEX or something else.

"I really doubt that Teflon wire would make that big of a difference on this coil.
And to get the Required Inductance, your going to need a Lot More Turns."

I've read the bbsailor article on fast monocoils for PI. So I've tested some teflon insulated
0.37mm diameter wire (a special wire for "hot" devices) and worked very well.
I've breaked the 8uS barrier that is very very good for me!
Yes, it's thicker than enamelled and not suitable for VLF kind of coils. But for PI is ok.

I have kilometers of old litz... very good quality but too thin for most applications.
It was used in crystal circuits...and radio in general...
I think it could stay in a museum ! (seems it was made in 40's, don't know for sure!)

Today it's not so used as in the past. Not so thin at least.

Best regards,
Max

[chemelec]

Hi Gary,
thanks for the infos. I'm quite far away from Canada so I have to add international transport expenses and taxes if I need to buy something outside my country.

In particular I'm interested in teflon insulated wire. I have some but need more. Have to buy.

Actually I need some wire at the moment...I have a dealer that sells to me also small lenght (but not under 100 meters). But at the moment I can't go there to buy (at about 80Km from my town) because I'm very busy and no time to travel ! There are many dealer here of this stuff for transformers/motors etc but most don't sell small quantities but entire kilometrics rolls so I've to travel a bit to get about quantity I need.

Best regards,
Max

My Wire Supplier is also Quite far away from me, but about 3 times a year I drive 4 hour, Each way to get more from him in Vancouver.
I Usually make it a 3 day trip and buy other stuff as well. But He doesn't have much Teflon wire and I don't really use it much either.

I use Litz wire sometimes, but I usually make my own.

I really doubt that Teflon wire would make that big of a difference on this coil. And to get the Required Inductance, your going to need a Lot More Turns.

By the way, an 8 Pound spool of 30AWG Enamel wire is about 25,000 Feet. One roll Keeps me going for a little while.

Take care.....Gary

[Max]

The Bigger Former is the top edge of a 4 liter Ice Cream Pail. The Smaller form is one I made out of ABS Plastic on my Metal Laithe. This Coil was ONLY Made for Bench Testing Purposes. Not for outside use.

Most Wire gauges are actually pretty accurate.
But there are Definate Variations in the Insulation Thickness, Especially from one manfacturer to the other. That insulation will make more of a difference than the actual small variations in the wire size.

Besides this Normal variation in Insulation Thickness, you can also get Double and Tripple Coated wire.

I stock 8 pound spools of about 15 different gauges, just for my expermenting. (between 16 to 40 AWG)
(My cost is $35.00 Canadian a Roll, A Really GOOD Price.)
I even have some Square and Rectangle Gauges.

I Specifically Designed this Split board as a Request from someone Back in 2004.
I don't really have any need for this detector. My only purpose was to make a Working PCB. So for my testing, I just use Whatever Capacitors I have on hand.
(This Board will Never actually be used in the field)

Yes, Silver Mica, NPO and some other fancy types will Definately be Better in some places on the board.

These Two boards PLUG Together with Single Inline Pins.
** For more convenient Testing and the need to Replace Parts, A set of Ribbon cables with these "Sip Pin Plugs" (male and Female Ends), can be easly made so the boards can be operated Side by Side.

Take care.....Gary

Hi Gary,
thanks for the infos. I'm quite far away from Canada so I have to add international transport expenses and taxes if I need to buy something outside my country.

In particular I'm interested in teflon insulated wire. I have some but need more. Have to buy.

Actually I need some wire at the moment...I have a dealer that sells to me also small lenght (but not under 100 meters). But at the moment I can't go there to buy (at about 80Km from my town) because I'm very busy and no time to travel ! There are many dealer here of this stuff for transformers/motors etc but most don't sell small quantities but entire kilometrics rolls so I've to travel a bit to get about quantity I need.

"** For more convenient Testing and the need to Replace Parts, A set of Ribbon cables with these "Sip Pin Plugs" (male and Female Ends), can be easly made so the boards can be operated Side by Side."

Good idea ! I'll do this way with next board.

Yes, I use also NPO quite often where needed.

I'm wounding the "rx bucking coil" on top of TX coil now...leaving it free for further adjustments, everything is AWG30. I'm using nails and plywood as temp support.

Best regards,
Max

[chemelec]

Hi Gary,
seems a very nice work. The split and the coil ! What have you used to make the formers ? seems plastic pvc but maybe I'm wrong.

Have you used plastic capacitors in other bandido circuits ? I can see only ceramic there. I've used e.g. polyester for 470nF and 100nF, thinking they are better than ceramic for that and better matched and ceramic for small values e.g. 100 pF. Are yours NPO type ? It makes some differences ?

I have to null also...now I'm wounding another tx coil because first was about AWG30 but there are small differences in wire gauge, so I have to wound new tx and rx from a new roll that is exactly 30AWG, red enamelled copper.
I'll use sope and capacitor...on RX to have good resonance point before trying to null.

Think that split board will fit easy in a smaller container, but normal is better
for testing, soldering without disconnecting tho halves etc. I like it very much now that I have to solder , experimenting, etc to find out what's wrong with my components.

Best regards,
Max

The Bigger Former is the top edge of a 4 liter Ice Cream Pail. The Smaller form is one I made out of ABS Plastic on my Metal Laithe. This Coil was ONLY Made for Bench Testing Purposes. Not for outside use.

Most Wire gauges are actually pretty accurate.
But there are Definate Variations in the Insulation Thickness, Especially from one manfacturer to the other. That insulation will make more of a difference than the actual small variations in the wire size.

Besides this Normal variation in Insulation Thickness, you can also get Double and Tripple Coated wire.

I stock 8 pound spools of about 15 different gauges, just for my expermenting. (between 16 to 40 AWG)
(My cost is $35.00 Canadian a Roll, A Really GOOD Price.)
I even have some Square and Rectangle Gauges.

I Specifically Designed this Split board as a Request from someone Back in 2004.
I don't really have any need for this detector. My only purpose was to make a Working PCB. So for my testing, I just use Whatever Capacitors I have on hand.
(This Board will Never actually be used in the field)

Yes, Silver Mica, NPO and some other fancy types will Definately be Better in some places on the board.

These Two boards PLUG Together with Single Inline Pins.
** For more convenient Testing and the need to Replace Parts, A set of Ribbon cables with these "Sip Pin Plugs" (male and Female Ends), can be easly made so the boards can be operated Side by Side.

Take care.....Gary