Nokta velox one coil reverse engineering

[Coilbrain]

Try this thread (found by doing a search on "Velox"):

https://www.geotech1.com/forums/foru...okta-velox-one

Note that Cirak only posted twice, 7 years ago. You can try to PM him.

https://www.linkedin.com/in/cirak/ I believe that's him but he's yet to reply to my messages

[Mike 55]

Good afternoon friends. A year ago I tried to build a large sensor for the Turkish Nokta Velox device One. https://www.youtube.com/watch v=8FXx90_RIAo. https://www.youtube.com/watch?v=MECapmy9BbE. The factory coil is not sorted it out. I assembled a test sensor in DD 9*11 foam. It works well for its size. On the forum:
http://www.md4u.ru/viewtopic.php?f=91&t=12092 briefly described. The coil circuit is similar to the coil for G-Maxx2 (so I think). I made a large DD20 sensor. By air 50 cm for an average maneta. In the ground 35 cm. The ground signal is very strong. I did not conduct any more experiments. Sorry for my English.

[Coilbrain]

Good afternoon friends. A year ago I tried to build a large sensor for the Turkish Nokta Velox device One. https://www.youtube.com/watch v=8FXx90_RIAo. https://www.youtube.com/watch?v=MECapmy9BbE. The factory coil is not sorted it out. I assembled a test sensor in DD 9*11 foam. It works well for its size. On the forum:
http://www.md4u.ru/viewtopic.php?f=91&t=12092 briefly described. The coil circuit is similar to the coil for G-Maxx2 (so I think). I made a large DD20 sensor. By air 50 cm for an average maneta. In the ground 35 cm. The ground signal is very strong. I did not conduct any more experiments. Sorry for my English.

very interested in your info can you share a bit more of your data ?

[Mike 55]

I am glad to help. I'll watch the recordings. What are you interested in?

[Coilbrain]

Mike 55 the youtube link you provided is not working (first one) and do you have pictures or inductance values resistance how many windings etc I'm working on a 45 cm coil. Can you supply info on the coil you built and how did you achieve compatibility (also what type of shielding did you use) .

[Coilbrain]

Mike 55 can you also attach files from russian forum as it cannot be viewed (only for members)

[Mike 55]

Good afternoon. Link: "https://www.youtube.com/watch?v=8FXx90_RIAo". The video shows how the Velox Detector sees a gold coin with a diameter of 36 mm. at a depth of 60 cm in clay?!
This struck me as a surprising result.
I don't see the NOKTA VELOX ONE schematic on the MD4U forum, I took it from the Geotech forum and reported it. The second diagram is the NOKTA VELOX ONE sensor diagram (my guess). I’ll try to write more about my sensors over the weekend. The transmitting coil can be measured. My Tx resistance on the factory sensor is 2.3 Ohm, I’ll write the inductance later. Copper wire 0.5 mm, later 0.8 mm!
Sensor diagram for construction:

[Mike 55]

https://www.youtube.com/watch?v=8FXx90_RIAo. You can search: Velox Detector; Depth Test Large Coil - Velox Dedektör; Derinlik Testi Buyuk Bobin.

[Coilbrain]

Mike 55 Thank you very much i appreciate it and waiting for you in the weekend

[Mike 55]

Good afternoon. A little about how I made the coil for the Nokta Velox One. I used the coil diagram from G-Maxx2 as a basis; I read on the forums that these devices are similar. The transmitting coil of the device at connector 4-5 shows 2.4 Ohm, 1.31 mH. Rx Failed to make a call. Before making a large sensor, I decided to repeat the factory one. Tx shook to the maximum voltage wire 0.5mm. The result was 51 turns, voltage 80 volts. Rx wire 0.2, approximately 170 turns. Rx resistance 38 Ohm, inductance 15.4 mH. Capacitor C- 5 nF. I selected the number of turns and capacity, comparing it with the factory one by cutting off ferrite, foil, and copper. The coil turned out to be 23*30 cm. The body is made of polystyrene foam. I used graphite as a screen.
To make a large sensor (Berta), I bought a 45*45 cm housing. Tx was wound 0.5 mm. The result was 35 turns, 3.9 Ohm, 1.32 mH. Rx approximately 109 turns. 44.6 Ohm, 15.7 mH, C - 5.45 nF. The coil was filled with resin, but when the resin polymerized, the balance disappeared. I made it again, the range for an average coin is about 45-47 cm in the air. It is not enough. I wound Tx with 0.8 mm copper wire. 2.0 Ohm, 1.32 mH, voltage 102 v. By air for a coin of 50-55 cm. Changed the number of turns
By installing the coil, changing the capacitance, installing a transistor with a large static current transfer coefficient h21e-Bc517.
Didn't get good results. There is a lot of interference and noise. Conducted tests on the ground. The first coil is working fine. Bertha sees the coin in the ground up to 35 cm, at 40 cm as ferrous metal. The ground signal and noise obscure the useful signal from the target. Resistance and inductance measured LCR-T4-H. Transistor Tester.

[Coilbrain]

so Mike 55 what you are saying is you didn't get the depth you needed nor the sensitivity ? can you please elaborate !

[Mike 55]

I couldn’t see the coin in the ground in a color deeper than 35 cm. Maybe it was necessary to change the number of turns and the capacitance of the capacitor? I bought a Nokta Velox One after repair, maybe the device is at fault.

[Coilbrain]

Mike 55 do you have whatsapp so we can remain in contact and share some files i have some data i can share and if you have some pointers you can give me while doing the build also what type of insulation did you use im trying the pic u attached but its low resolution if you can upload a bette quality one

[Mike 55]

Email is better. WhatsApp is full of spammers and scammers. Please write your email. I haven't used Nokta Velox One for a long time. Now I'm making a sensor for GARRETT ACE APEX. Decipher the question what type of insulation? Maybe the sensor circuit is wrong? The best thing to do is to disassemble the factory sensor.

[Coilbrain]

Mike 55 [email protected]