SMT Bandito Info/Build

[Koala]

I like Mouser good prices! I didn't know you could share a project. I wonder if you can add two projects together?
I'd like to be able to reorder the same parts again later if I get more boards. Can you order multiples of a project?

I took a copy of that board and am comparing it to our board looking for mistakes + improvements.

Yes you can order multiples of a project there is a quantity box not sure but as you can have several different project name can't see there being a problem in combining. Pretty sure you just pull down the other project name and hit buy and it would list both

Now we are on 0805 they have all but the 2.7M resistors as thin film all but two @ .5% and 25ppm/c and most are £0.06 and the others are only a few pence more no more silly prices in 0805 size

Few mistakes in it but see if this works

http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=3d6026fa2b

[Silver Dollar]

Now that's what I'm talking about! 0.5% and dirt cheap. gotta love it! Mouser is the best!

Here's some pics of the Dual Layout, it's my first try at board layout it's kinda fun, like a puzzle.
I still have the original, original with mods, with mods and SmD caps and this monster;

[Koala]

"I'm not sure I will even have more boards made as no one seems interested in building some. I
probably have enough boards around to do what I need..."

Does not have the following on here as the TGS.


Bandido does not have the "air" depth of some of the more modern machines. Pretty sure much of it is psychological and the grass is greener on the other side. People who have had them even pay over the odds to replace with a secondhand one after playing with the latest bells and whistles detector.

I went on a rally recently with my IDX did better than most so nothing wrong with old tech.

Your new layout looks clean

I can give you write privileges to the parts list and we can both work with the same list but don't know if it will work with US/UK difference.

[Silver Dollar]

Some of the depth problem could be related to the 5V used for the transmitter. If you noticed I sent the battery voltage
over there to allow a second regulator to isolate the transmitter but you could also use 9V for it to gain some depth.

I might try running the
TGSL on +-12V to see how much difference a bigger supply makes too. The +5V -3V may loose some depth too.

The Bandito is very similar to TGSL and Tesoro called the Umax II a deeper design though we don't have schematics
from each one to see how it evolved.

I like the non motion PP myself. I may experiment with allowing a slower search speed too.

[Koala]

updated the parts list now includes all the IC's with the best specs I could find ie lowest offset, lowest current

non motion all metal mode interested me also as I normally hunt in all metal and switch to disc when over the target seem to miss less that way plus I can hear via the threshold tone when I am near an occupation area.

[Silver Dollar]

Cool. Good work! Thanks for setting that up for us. I might get 4 sets.
I have a lot of the parts but they are "only" 1% and I'm not sure if thin or thick film.

[Koala]

started on the capacitors did not reilise they were all different sizes so will have to start again

can't find the 10uf on the board

on the board there are two over the RX but on the schematics there is only one.

have you recieved your board yet. Transistor that's on the CD4024 has very small pads might have to find a different transistor for it

C14-8.2pf :0805
C13-10pf :1206
C10-22pf C18-22pf
C16-39pf :0805
C9-100pf :0805
C12-180pf :0805
C22-10nf C2 4-10nf C23-10nf :1206
C32-22nf C33-22nf :1206
C15-33nf :through 5mm
C2-47nf :through 5mm TX coil
C19-100nf C21-100nf C20-100nf C34-100nf C36-100nf C25-100nf C28-10nf C29-10nf C35-10nf :1206
C17-220nf :1206
C1-470nf :through 5 TX COIL
C37-0.47Uf C31-0.47Uf C30-0.47Uf :1206
C38-4.7Uf C39-4.7Uf :through 2mm
C7-10Uf
C4-100UF C5-100UF C42-100UF :through 3.5
C6-220Uf C8-220Uf :through 3.5

C3-??
C11-??
C26-??
C27-??
C40-??

[Koala]

Tesoro used a three turn POT for the ground. Very expensive at Mouser. So added a 1 turn. Might knock it off and use a 10 turn from eBay. Used a 10 turn on my IDX works very well. Does not take too long to adjust as you are not moving it far from the last time you used the detector.

[Silver Dollar]

I think the 10uf is a mistake Sorry! I thought the same thing get the pots from Ebay.

The optional cap for the RX us a small value (1 - 2 pf) to tune it a bit. Probably not needed.

No board yet and I wonder if I ordered one as I had emailed Silver Dog and then sent him some money
and thought I was all set but then he PM'ed me here saying he has a board available for me. Not sure
what's going on. Maybe he has one more?

I got a reply from Paypal saying I have a package coming...

[Koala]

fasted I have seen from the USA is a week and a half by air and longest via overland is a month

take it
C3-??
C11-??
C26-??
C27-??
C40-??

Don't exist have not got access to the program on the laptop as it's running OS X

[Silver Dollar]

Here's my list. Some caps were on other schematics I guess.

C1-470nf
C2-47nf
C3-??
C4-100UF
C5-100UF
C6-220Uf
C7-10Uf
C8-220Uf
C9-100pf
C10-22pf
C11-??
C12-180pf
C13-10pf
C14-8.2pf
C15-33nf
C16-39pf
C17-220nf
C18-22pf
C19-100nf
C20-100nf
C21-100nf
C22-10nf
C23-10nf
C24-10nf
C25-100nf
C26-??
C27-??
C28-10nf
C29-10nf
C30-0.47Uf
C31-0.47Uf
C32-22nf
C33-22nf
C34-100nf
C35-10nf
C36-100nf
C37-0.47Uf
C38-4.7Uf
C39-4.7Uf
C40-??
C42-100UF

[Silver Dollar]

I just scored a real Bandito from back in the day. It's the original 1990's one
with 2 boards (??). No one has documented the difference between that one
(with 2 batteries) and the newer ones. I'll have to check it out!.

I'll probably put this SMT one in a Tracker case as my efforts to improve it
have been futile! There's just the question of should I use the Tracker coil or
a DD with Minelab specs...

[Koala]

I just scored a real Bandito from back in the day. It's the original 1990's one
with 2 boards (??). No one has documented the difference between that one
(with 2 batteries) and the newer ones. I'll have to check it out!.

I'll probably put this SMT one in a Tracker case as my efforts to improve it
have been futile! There's just the question of should I use the Tracker coil or
a DD with Minelab specs...

Excellent you will be able to compare the performance with the Monte nail board test as the original is regarded as the best Tesoro in an iron infested area or is that a myth. I for one will be interested in the results. I suspect there will be nothing between them. I have noticed on YouTube that the audio of the original is slightly sharper (very nice short sharp beep) on targets but that could be the quality of the videos. Where as the newer umax seems softer longer beep.

BOM on Mouser now has caps resistor transistors and diodes added another 2 standard diodes to try before swapping to schottky


What is the advantage of the Minlab spec coils of the standard Tesoro

[Silver Dollar]

TX has less windings so more field strength (ampturns).
RX has more turns so more signal.

[Silver Dollar]

If you look in the IGSL thread around page 5 you will find info on the Minelab mod.

http://www.geotech1.com/forums/showthread.php?17861-IGSL/page5&highlight=igsl

Basically Ivonic got tired of making coils and could buy the Minelab ones for a
reasonable price so he tried a different oscillator and got good results. The
coil is TX 1 mh - 45 Turns
RX 14.7 mh - 200 Turns

VS TX 5.9 mh - 100 turns
RX 6.5 mh - 105 turns

So the TX generates more ampturns and the reciever gets more signal.

If I was using a stock Tesoro I'd use that but winding my own I'd use the Minelab one.
Not sure in the ground how much difference there is but it should be a bit better....