Barracuda.....update(2)

Hi,
I just looked at the datasheet, the power supply schematic, the PCB layout, and your picture of your PCB. The negative supply circuit looks correct. I would double check to make sure the part is a 79l05 installed on the PCB and if so, pull the output leg out of the board so it is contacting nothing and measure the output. It will most likely read properly indicating that the power supply is working ok but your PCB had a problem elsewhere.
Good luck,
Boattow

Hi,
Your 7660 sounds like it is working correctly if you have -11.7v out of it. That means the problem has to be with the 79l05 regulator. First, I would recheck and make sure it is wired correctly. If it is, then look again at the part number and verify that it is a 79l05 soldered in there. If it is, then I would unsolder the output leg of the regulator and pull it up out of the board. Measure the voltage on it. If it is still -2.5V, then replace it. If it is now reading -5V, then you have a problem elsewhere loading the output of the regulator. These 79L series regulators can only source 100ma so it wouldn't take much of a problem somewhere else to load it down and read low. That is most likely going to be your problem.
Good luck,
Boattow

[Leto]

still non working

HI
Thank you Geo and Michael.
Michael: I verified the 7xL05 pinouts and as I see from here both are installed right (no mistake). Please download both datasheets!!
79l05 (gnd-in-out)
78l05(out-gnd-in)
To your list I would add:
C1 is missing but this can be easily installed off-board.
Have put 1M resistor and C8 on solder side..

Can not understand that power supply:confused: ...
ICL7660 Vout is at -11.7V
79L05 Vout (Vss) is at -2.5V ... Why use two negative converters in row???
78L05 Vout (Vdd) is regular +5V.... Should not be Vdd and Vss opposite (-5/+5V)??
NE5534 pin6 is at 4.5V and no pot no matter how much I turn it makes no difference... also constant 337hz from speaker - same as coil.
Almost forgot Geo:
Oscilator is working! at 337Hz completly stable. It's driving coil (measured with DMM) with 6.6V at 0.43A So at least this is working..
I have replaced 2N transistors with appropriate BFs.. Maybe I should use originals??
So this is sadly it ... Opened to any ideas .... Can someone figure out that power supp.
Is this working circuit at all??? :confused:

[mbiondo]

79L05 Pin numbers

Leto, did you verify the pin connections on your 79L05 rather than going by the schematic? The datasheet I have shows Pin 1 - GRD; Pin 2 - IN; Pin 3 -OUT. The schematic shows incorrect pin numbers ---

If the schematic is correct, I also found several errors with the PCB layout:
Pin numbers on the 78L05
R22 missing
R25 missing
R29 pin 1 open - s/b to Vdd
R40 shorted
east side (on PCB layout) of C8 incorrect; should go U1 - pin 9 and C9

Michael

[Geo]

Try

Hi Leto. Try to connect the pin7 of U1(CD40106) to -Bat no to Vss . To work properly the ICL7660 we must have oscilations from U1. So connect pin7 to gnd to make the gates to oscilate . Good luck .

[Leto]

EEs help needed

Hi,
I completed the board and it's not working :confused: , so help is needed.
Can someone check the power supply:
Something is wrong with Vss - can not make this negative.
I wired +c18 to Vbat, but this not help either...
There are also few other mistakes on PCB posted on this forum but will discuss those later.

[nelson]

Barracuda

Hi Leto and Geo

Yes i agree, this circuit and comments about barracuda, looks promising.
The circuit looks not to complicate to build it.
I was looking to my local electronics parts supplier and i can get almost everything from my country, the rest will be supply by foring stores.
Good work Leto, after you finish it, please post results.
I have also to finish my Delta Pulse that is turning me out of my mind.
I ll start building barracuda after january 20, because by now i ll lieve on vacations to the beach and i ll carry on my Clone PI mateal detector that is doing a good job for beach hunting.
Finally i have collected schematics for barracuda and pcb, but if you have any other information that can help, would you matter to share it.
My email is [email protected]
Best regards and happy new year to everyone.
Nelson
Santiago-CHILE, SA.

Timing on this PI is done with Hex Schmitt Trigger!
There is resistor missing on PCB -> 1M between pin2 and pin6 of NE5534..

Also a question for EEs:
Can I replace 2N5485 and 2N5484 with 2N3819 in this circuit??

There's not much information available on net about Barracuda PI MD.. it was produced by Anchor Electronics and costed about $795
Nelson I'm just about to finish this project, few transistors and caps is all I'm missing.

[Geo]

Can I replace 2N5485 and 2N5484 with 2N3819 in this circuit??

.

I believe that there is not problem .
Try it but i think that you must change the pins (gate and source). Also you can try BF245
Good Luck

[Leto]

Anchor Electronics

Timing on this PI is done with Hex Schmitt Trigger!
There is resistor missing on PCB -> 1M between pin2 and pin6 of NE5534..

Also a question for EEs:
Can I replace 2N5485 and 2N5484 with 2N3819 in this circuit??

There's not much information available on net about Barracuda PI MD.. it was produced by Anchor Electronics and costed about $795
Nelson I'm just about to finish this project, few transistors and caps is all I'm missing.

[Geo]

One of the best PI detectors. It is about the same with some other detectors (if i remember good with whites...)

[nelson]

Barracuda performance

Does any one have information on how barracuda pi performs. Any expirence with it?
Also, does any of the components put any problem to find out it?
Regards
Nelson

Hi. At this PCB there is a problem. Is absent the above side. Here is the right.

Geo

[Geo]

http://thunting.com/geotech/forums/s...d.php4?t=11238

Hi. At this PCB there is a problem. Is absent the above side. Here is the right.

Geo

[Roberto]

PCB barracuda !!!

http://thunting.com/geotech/forums/s...d.php4?t=11238

[ismail surek]

hii to all

i need to Barracuda s PCB
could you help me_?
good working

USE IRFANVIEW FREE PROGRAM

Find in the web Irfanview download. Install this program on your computer.

When you wish print a circuit select in printer box, feature option, "landscape". Select "best fit to page". With this program you can print large plans. You can costumize, etc.