underwater waterproof Tiger Shark. VLF for salt water (not same as tesoro tiger shark)

[Thomas]

Yes, kt315, thank you for bringing this very interesting detector to our forum, one of the things I noticed, is the use of the low power audio amp to drive the transmitter coil? I have seen that before but not sure why it is used. Maybe someone can say why.

[sinclairuser]

Good day!
I am glad that the forum had this issue.
Unfortunately, I do not speak English, and I have to use online translator.
I am Alexander Serbin (from Kharkov, Ukraine), the author of this instrument.
Special thanks KT315, for this thread in the forum.

thanks to you, and kt315 for sharing it here!.

[AlexSerbin]

Hi hispalba!
Thank you for your understanding (my bad english)!
My fee for a metal detector: 2 to 5x11 cm...
Thomas, why do you think that the transmitter in the scheme of my low-power detector?
This metal detector is used quartz oscillator stabilized. Frequency can be selected: 8, 16, 32 kHz.
Buildup produced low frequency amplifier IC MC 34119 (for a cleaner signal sine).
Transmitter coil - series resonance. At the exit, we have decent power. I personally do it a little bit in the device suppressed resistor R22 (larger than in the circuit).
I do not need a very large capacity to work better in trashy areas.

Sincerely, Alex

[Thomas]

Thank you for the answer, now I understand. I my have more questions later

[Thomas]

I do not want you to think that I said that your detector is low power, I think It is a excellent detector, The data sheet for the MC34119 call it a low power audio amp. I just wanted to understand that choice. I have just begun to learn about Metal Detectors, It is the translator. Please do not think I am disrespectful to you.

[AlexSerbin]

I do not want you to think that I said that your detector is low power, I think It is a excellent detector, The data sheet for the MC34119 call it a low power audio amp. I just wanted to understand that choice. I have just begun to learn about Metal Detectors, It is the translator. Please do not think I am disrespectful to you.

no problem

[AlexSerbin]

Hi!
Here are a few photos of my instrument boards, first find (April 2013).
Unfortunately, could only give the link ...
1. http://yadi.sk/d/bYwAv4wkG59oP
2. http://yadi.sk/d/2E8-eczHGRjqR
3. http://yadi.sk/d/ZUAGAm8-GRjpr
4. http://yadi.sk/d/aOQP6LKaG59pg
5. http://yadi.sk/d/zb3-HuXMG59pz

Regards, Alex

[Thomas]

Alex, can you say the size of the Concentric coil?

[SVEN1]

Very nice would like to know more.

[AlexSerbin]

Alex, can you say the size of the Concentric coil?

Yes, of course.
Diameter of my sensors - 20-25 cm Winding data by wire, does not change. Only changes the capacitance (tuning circuit in resonance).

[AlexSerbin]

Currently preparing an article for their website (www.kamrad-club.ru), which will be more information on this metal detector. Already had to put it, but that's already 3 days to a server problem.
Unfortunately for you friends, the planned article in Russian.
Because preparation of the article, some information as I can not lay here. Once posted an article on the website immediately able to duplicate, or even try to translate it and put it here.

...Now we have in Ukraine is gorgeous frosty, snowy winter ... And of course I would go again, something to design.
Ideas already. And it will be a new twist in this scheme.
At this time my Tiger Shark scheme will be complemented by units from Tesoro Lobo ...

Well, perhaps some more photos Tiger Shark:
1. http://yadi.sk/d/KyrATHx3GVgeu
2. http://yadi.sk/d/uG5Tm1afGVgeb
3. http://yadi.sk/d/AmTKetirGVgeP
4. http://yadi.sk/d/G2EtZ08BGVgdz
5. http://yadi.sk/d/R_kOOf8uGVgdp
6. http://yadi.sk/d/ogBB_LpaGVgdY

Sincerely, Alex.

[Thomas]

Thank you for answering my coil question , now I have another, Is the air valve to pressurize the control box?

[SVEN1]

Just guessing. On my early waterproof PI, I had a leak that was almost impossible to find. I put an air valve on it, attached a bike tire pump to the valve and pumped some air into it.
Placed the box underwater and found the leaks instantly. Secondly a bit of air pressure into the case may just prevent water from leaking in for awhile, all depends how deep you take the water unit. Water pressure increases the deeper you go.

[AlexSerbin]

Glad I could be useful.

[AlexSerbin]

That instrument keep the board in the program Sprint Layot 5.0
Good luck to all!
http://drive.google.com/file/d/0BwE6...it?usp=sharing