Nokta velox one coil reverse engineering

[Carl-NC]

You need an LCR meter to measure inductance & capacitance. You can't reasonably do this job without one.
Here is my take on the internals:


Having the cable gland on the RX side is a bit unusual, you normally want it on the TX side to minimize RX pickup of cable flexing. Anyway, the single wire straight up the middle is a ground drain embedded in the shield of the upper housing. There is a second drain wire that is embedded in the shield paint of the lower housing (under the TX winding, you can't see it). These are connected to the RX(-) side, which acts as the shield ground connection all the way to the main box. Likely the 5-pin connector only uses 4 pins.

I agree with the others that the 3-pin device is probably a trim pot. The proper values and pot setting will be difficult to determine. This is where you will need an oscope and maybe a signal generator.

[pito]

what is tha wire for ? = Shield wire, not captured on Xray, or could be the single vertical wire on the center.


the fifth wire (ground wire ) can be connected to washer under nut of cable fitter.

[pito]

high res pictures = the fifth pin may be not used, on the first PCB pad (on the top ) you have
1. ground wire bottom side
2.ground wire bottom top ide
3. Rx wire

[kt315]

I highly appreciate your input pito and all members as well I was wondering how can I get accurate readings of set capacitors and coils so I may replicate, also as part of the project I'm trying to make a bigger coil and possibly a better one in the hopes of going deeper even though at the cost of no longer picking up small objects (small objects not my target all areas I wanna work have very deep large objects). furthermore, if I were to produce a larger coil to accomplish set goal can it have same specs as the small one but upscaled or it has to be reworked from scratch ? sorry for all these questions I am not expert at this I am learning here

on your pic low capacitor has to be change on a resistor.

[Coilbrain]

can someone point me to a thread or a tutorial that might help me execute these steps so I may replicate them

[Coilbrain]

You need to use an LCR meter such as this one -> https://www.amazon.co.uk/Capacitance...ps%2C95&sr=8-5

does this cheap LCR meter have the accuracy to conduct the tests ? or do i need a benchtop lab grade one ?

[Carl-NC]

2.5% accuracy on reactance is sufficient.
I don't know of a tutorial on building DD coils. Various people have posted info on what they've done, you'll have to poke around to find the info.

[ivconic]

The percentage of accuracy of the measuring instrument is completely irrelevant; IN THE CASE when you measure the original and when you make a copy using the same instrument and measurements.
Accurate data is important only when generating a database and transferring the same data to others.
If the coil is realistically 2mH and you measure 2.2mH with a cheap instrument; when you make a copy, you use the same instrument to check that you have wound 2.2 mH, which in reality will be 2 mH again.
Much more important is the accuracy of the ratio between TX/RX coils, provided that the coil is not wideband. If it is wideband; then it doesn't matter even then.
...
I only had the opportunity to work with the Velox One once for a few hours. It was the first truly successful machine by Nokta (Macro). Until then, they made bad detectors.
And from Velox One, their "recovery" starts and they make good machines.
Then (x years ago) I publicly suspected here on the forum that it was a copy of the XP Gold Max Power detector. Because the Velox One behaved identically on the field.
It would be good to find out.

[kt315]

My aim here is to produce a bigger coil tuned for deeper larger objects relics cashes and

Delta Pulse coil is 1 meter on 1 meter. you can dig on 1.5+ meter depth.

[kt315]

[Smirnov-Arta]

. you can dig on 1.5+ meter depth.

The minimum dimensions of the target at a depth of 1.5m with a 1x1m coil?

[kt315]

The minimum dimensions of the target at a depth of 1.5m with a 1x1m coil?

standart test on cola can. but this is not good target for the test because small. kaska holm douche german helmet is good.

[Smirnov-Arta]

///

I'm really sorry that I asked you that!!! Because I knew the answer in advance. I wanted the person who asked about the search for money/coins to hear it from an experienced person like you!

[Coilbrain]

The percentage of accuracy of the measuring instrument is completely irrelevant; IN THE CASE when you measure the original and when you make a copy using the same instrument and measurements.
Accurate data is important only when generating a database and transferring the same data to others.
If the coil is realistically 2mH and you measure 2.2mH with a cheap instrument; when you make a copy, you use the same instrument to check that you have wound 2.2 mH, which in reality will be 2 mH again.
Much more important is the accuracy of the ratio between TX/RX coils, provided that the coil is not wideband. If it is wideband; then it doesn't matter even then.
...
I only had the opportunity to work with the Velox One once for a few hours. It was the first truly successful machine by Nokta (Macro). Until then, they made bad detectors.
And from Velox One, their "recovery" starts and they make good machines.
Then (x years ago) I publicly suspected here on the forum that it was a copy of the XP Gold Max Power detector. Because the Velox One behaved identically on the field.
It would be good to find out.

indeed there are rumors and speculations going around for a long time that nokta reverse engineers and copies competitors, and regarding the meter i agree if its the same device doing both reading and calibrating

[Coilbrain]

Would this oscilloscope do the trick for designing the coil

https://www.aliexpress.com/item/1005...510002684784_2