Bandido uMax not working

[solmer2]

I fixed all the cables and checked them twice but Bandido 2 uMax don't work.

When I try to turn it on I only get a weird sound (very short) similar to a click.
I've that sound recorded you can download it from the link:

http://www.megaupload.com/?d=758IB4E2

I've not idea what is the problem, a bad IC ¿? Audio block ¿?
Any help will be appreciated. I need to resurrect my machine

Thanks in advance for your invaluable help,

Good luck and happy finds !

[Merc]

Are you working on an original factory built Bandido II or one you built yourself?

Merc

[solmer2]

Hi Merc, my unit is an original one, Tesoro Bandido II uMax, I only get a click when i turn on the machine, I don't hear the battery test tone for a few seconds but a click.

Thanks in advance.


Solmer

[Merc]

Check the supply voltages. I think it should be +5V and -4V on the Bandido II. If the +5V is good but the -4V is bad then check your coil connections. Negative supply relies on the transmit coil oscillator working properly.

Merc

[solmer2]

Bandido II uMax

Hi Merc, excuse my ignorance but i don't know where to check for +5V and -4V, should I check them at the board? My electronic knowledge is a bit rusty, ACtually I work with sound and video , I left analog electronic ten years ago.....

Thanks in advance for your time and help.

[Merc]

Check the voltages on one of the 8 pin ICs. All are op-amps or comparators with the same pin arrangements....positive supply on pin 8 and negative supply on pin 4.

Merc

[solmer2]

Thanks again for your help I'll check it on Monday 'cause I need to replace my Multimeter . I guess that the problem is a bad IC, if i turn on the unit it emits a short click and if i turn off and then on again i don't get any sound, i have to remove the battery and wait a few seconds to hear the click again.... extrange....

Thanks one more time.
Cheers.

[Merc]

Could be an IC but it could also be a connection problem to the search coil. If the search coil is not properly connected the detector will not give the usual battery check beep on power-up.

Merc

[solmer2]

Opppss , I need to check coil connector, I disassembled it some months ago due a problem with the contacts.... I'll fix it soon, is my backup machine, i have a minelab explorer as main unit but sometimes i need to relax my arm ! it weighs a ton

Thanks again for your time

Cheers,

Solmer

[Merc]

I'm not sure if all Tesoro coils use the same color wires in the cable, however, here is the way my white 8" open center coil for my Golden Sabre is wired.

1 Red
2 Not Connected
3 Green
4 White
5 Shield Drain Wire

[solmer2]

Voltages

Hi, I have checked the voltages and I get 9volts between gnd and + Batt. so battery is ok.
I've checked the Volt. in the ICs and I got +5v in all Ics (Between gnd and pin 8 (for smd 8pin ics) or (for 14 smd ics). I got 4 volts (or -4v changing the test leads) between Vcc(pin 8 or 14) and pin Vee(pin 4 or 7).

Is this correct?

My connector is wired as follows:
(looking at the front of the male conn.)

(4 3)
( 5 )
(2 1)
(___)

pin 1 Violet
pin 2 nc
pin 3 Orange
pin 4 Grey
pin 5 GND (shield, no colour)

I've checked the coil connector too (I've not an oscilloscope to test the signals) I've used my multimeter and i got

20-21 Ohms between 1-3
20-21 Ohms between 5-3
40-41 Ohms between 3-4

I've checked that the connector is firmly attached but stills not working....



Thanks again for your time and help

Cheers.

[woody]

try swapping pin 1 violet and pin 3 orange around

[solmer2]

Bandido II uMax FIXED !!!!

Hi Merc and Woody !

My Bandido is working again ! Thanks for bringing it to life again.

Now my arm can rest.

Thank for your time and support.

Good luck and happy finds!

Solmer

[solmer2]

And the problem was...

Oops, I forgot to explain the problem..... I disassembled the unit this summer to make it waterproof and everything was OK. A few days after building my waterproof unit I bought a Tesoro Tiger Shark so I decided to reverse the process and put the Bandido back into the original box. I connected everything OK but I made a mistake soldering Violet wire on the Orange pin..... A stupid mistake .

Thanks again.
PS: I'll post some pictures of my waterproof Bandido.

Solmer