'KROT2-XM' (mole), new project Xmega32

[darkfibre]

And the menu options explained;

http://radiodom.org/K2-48_GAIN-S_opisanie.doc

[reptooyep]

Hi Smity,
I use the K2-GAIN-SGold firmware. I can't see "ZERO ADC" menu in this firmware.
I've seen those explanation once before but they don't explain how to mechanicaly tune the coil. Is it the same methode as the TGSL project (with an oscilloscope) ?

For darkfibre :
I started few days ago to translate this file but as i said earlyer, this is for the previous firmware, not for K2-GAIN-SGold.

Thanks for hepling

[WM6]

I started few days ago to translate this file

Is this translation not good enough for your needs:

http://www.geotech1.com/forums/showt...727#post182727

[reptooyep]

Your translation is good but i does not help me about the coil nulling and the phase relation between TX and RX ..
Thanks

[WM6]

Coil nulling is separate problem from Mole settings procedure.

You can use signal generator (on TX coil) and AVO meter with 200mV range (on RX coil) for coil nulling, following known VLF/IB coil nulling way. Be careful in next step with coil potting, to not re-tune your coil.

If coil working frequency is set in Mole working frequencies range, Mole can manage your coil using settings procedure (proper phase inclusive).

[reptooyep]

Thanks WM6,
May i use the MOLE TX circuit to null the coil ?
I should detect the tx frequency in setting menu, then, i null the coil by the TGSL methode with the oscilloscope ? Is that right ?

I have another question, the TX capacitor i use is a 300nF one (i used the post 8 values) and my coil has an inductance of 22.8mH.
The frequency should be :
1/(2*PI*RootSquare(L*C))

The mole unit gives me 8836 HZ but by calculation (22.8mH and 300nF, i find 1926HZ). I don't understand why..

[timekiller]

Hi Smity,
I use the K2-GAIN-SGold firmware. I can't see "ZERO ADC" menu in this firmware.
I've seen those explanation once before but they don't explain how to mechanicaly tune the coil. Is it the same methode as the TGSL project (with an oscilloscope) ?

For darkfibre :
I started few days ago to translate this file but as i said earlyer, this is for the previous firmware, not for K2-GAIN-SGold.

Thanks for hepling

"ZERO ADC" not present in this firmware K2-GAIN-SGold . From GAIN-SP - "ZERO ADC" not present.
The mole unit gives me 8836 HZ but by calculation (22.8mH and 300nF, i find 1926HZ). I don't understand why..
Calculation is wrong . Measurement is better to place directly on the sensor.

[reptooyep]

Sorry, i'm stupid
i took the RX inductance for TX calculation ..
I have Ltx=1.06mH
By calculation, i find 8928 HZ ...
The capacitor should not be excactly 300nF, that explain the difference (8836HZ on the mole).

There is no ZERO ADC menu, do you mean that it's now automatic ?

[timekiller]

There is no ZERO ADC menu, do you mean that it's now automatic ?
Yes , it's now automatic .You can get what you want frequency change C0 , coil must be Balancing on this frequency or close.

[reptooyep]

What kind of capacitor is the best for C0 ? I use 3X100nF (100v) polystyren film capacitors in parallel (military quality).
If i can't get a null on RX, what i can do is adjusting the TX frequency a bit and try again nulling.
What i want to know is the phase relation between rx and tx.

[timekiller]

Capacitors as WIMA are suitable . Try to use one capacitor, not in package. There are different ways to achieve balance , I do not know who would be suitable for your skills. voltage Rx must be changed in + ,from 50-60 mV without turning phase - it's my understanding .

[smity]

You need...
1. Set the resonance TX.
I advise you, for good sensitivity, frequency set 10-15 kHz.
2. Balance the coils.
3. Perform SETUP (calibration) on the ferrite phase.


Phase, "Mole" itself, will automatically adjust.

[reptooyep]

Hi, I hope someone can explain what i'm doing wrong :
I t tryed several C1 values (150nF; 220 nF and 300nF).
For each TX frequency, i can't have a RX signal less than 2 or 3 volts (seen on the oscilloscope AC coupling).
I use for TX : 45turns of 0.4mm (1.06 mH, 3.6 ohm)
and for RX : 200turns of 0.15mm (L=22.8mH, R=127ohms)
I found those data on post 8, this should be good for a 8-9khz TX.
The rest of the detector seems to work as it should.
What can i do for that ?

Maybe i sould wind anothe coil and take of turns until i can have a good nulling ?

I don't know

[timekiller]

Hello, as I wrote ratio inductance Rx Tx too much . Balancing becomes difficult . Now you'll need a little magic a correction Rx coil , or to make a new Rx .

[reptooyep]

Hello, as I wrote ratio inductance Rx Tx too much . Balancing becomes difficult . Now you'll need a little magic a correction Rx coil , or to make a new Rx .

Oh, too bad for me.
What do you mean by "l little magic a correction" ?
Too late to modify my coil. Hopefully, i have some 0.15mm wire. But i don't have enough of 0.4mm for a new TX.
What would you advice me, make a new TX or make a new RX ?
Thanks for helping, this is my first SMD project but my biggest failing is to finish the whole assembly before tuning ...