Carl's fluxgate Gradiometer ckt.

[Krzysztof]

Hi Damiafix.
Power supply decoupling is typically always use. There must be the same. There may be several nH or a dozen om. It may be a few beads ferite. FGM-3 is resistant to changes in power to a limited extent but you can always go further to protect.
Moreover, the same as the generator produces a low distortion power line in moments of change in H / L and L / H output (jumping power change).
FGM-3 is much more sensitive to temperature changes. It is good to put it in a Styrofoam.
For the trials on the table, the lack of security does nothing!
Best regards Chris.
P.S.
Subject of the film. Discard R6 and add 2.2 Kom and you will have glitches at the beginning of the measuring scale.

[damiafix]

Dear Chris,
thanks again for your help, I've a question, about the inductors L1/L2 connected on the Vcc Pin of the two sensors:
I think that I've damaged one of this inductors, maybe the internal wire is broken (infact when I move it sometime work, sometime no) I've checked the welds on the cable, but the problem is inside the component, so for now I've replaced it with a 47uHy inductor, and it seem work correctly:




Reading the Carl's document about the FMX-1 I've found something of strange about the L1/L2's value, he wrote 56nHy but on the speake's components list I read that the value is 56uHy and that could to be replaced with a 10ohm resistor, look yourself:





Unfortunately here it's very hard find a 56uHy inductor like the original.
Please, could you tell me the function of this inductor?
In every case, I should to replace also the second inductor with the same component, it must to be equal, for a good work!
What do you think?

All the best, Dam.

[Krzysztof]

Hi Damiafix, TNX.
Give conditions how in # 52 and listen what difference!
Best regards Chris

[damiafix]

Dear Chris,
this is part of the test 9:

one fluxgate FGM3 sensor connected, pin 17/18 of the SCL007 wired, and the logic analyzer connected on the pcb, r6 is around 4,5KΩ.

One sensor test


All the best, Dam.

P.S. I'm sorry for the video quality I've realized it with a easy photocamera.

[Krzysztof]

Hi Epitopios.
50% bug's.
Since R6 = 0 is directly to the Q1 emitter Pin14/15. At the same time Pin14/15 resistor to GND 2.2 Kom!
1NF from the point of R9-R10 to GND. It is to be low-pass filter!
Dle experiment C5 3.3 microF. Please listen to the answer V / f to select the better / more sensitive.
Best regards Chris.

[epitopios]

Hi Krzysztof
I make some changes as you write.
Can you see them and rebuild the foto correct if somewhere Iam wrong ??

regards, epitopios

[Krzysztof]

Hi Epitopios.
Response to post # 48th
Read # 12!
For the test on the table so qasi logic analyzer is very helpful. Can be used to test the digital lines and control drive the asking. Eats a little power on the table but do not mind.
Of course you can use these open eight lines D0-D7 to send them on the LCD but through an additional microcontroller!
Best regards Chris.

[Krzysztof]

Hi Epitopios.
Subject # 47 Fig1.
Do not.
Read # 26 Linia3-8. Test4, 5, 6.
Additional 100om resistor R6 the other hand, directly to GND.
Only for testing as a protection against short circuits Q1 in the case of R6=0. Then, exterior Q1 activation of voltage from another potentiometer. Serves to control the action of the V / f .
Subject # 47 Fig2.
Subject C7. Any type. OK.
I think I will improve the transfer of low frequencies.
Subject 1nF. Do not.
Read # 42 3rd Position.
1-10nF capacitor from this point to GND. In order to mute noise (jitter), and high harmonics.
Subject 2,2Kom. Do not.
Read # 42 1rd Position.
Listen to the # 41 MP3 from the sticky results Damiafix.
AD557 has an internal resistor 1.6 Kom and is still a little too big to stretch the scale at low frequencies.
I propose to give 2.2 Kom parallel between Pin14,15 and Pin13=GND.
Of course, R6 = 0 is removed.
In an experiment, you can just reduce the C5 up 3,3mikroF and C6 very much up to 10nF.
Best regards Chris.

[epitopios]

Hi Epitopios.
Hello again!

See post #19. The photograph you have eight lines from the center of a plate to the box, if they show something?

Best regards Chris.

dear Krzysztof , the 8 lines you see , I put them from the begining
and I just left them as it was , no reason
do you think I can use them ???
regards , epitopios

[epitopios]

R6 to GND through resistor 100om - Security transistors.

You mean something like that ???
and also :

C7 = 2,2mF : IS IT ELECTROLYTIC CAPACITOR OR SIMPE ??
are everything correct ??
thanks in advance

[Krzysztof]

Hi Epitopios.
Hello again!

cables: no-where ,.................
no measure there

See post #19. The photograph you have eight lines from the center of a plate to the box, if they show something?

did you see better different from your Gradiometer with these changes ??

Cosmetic changes, better sensitivity and a nice sound. As if the rose or the steering level of sound (sensitivity range) at low frequencies.

you have a 9 volt or 12volt/7Amh baterry ?

I do not have FMG3, Carl MAG, MAG EPE. I have my own construction of the battery-powered mobile phone 3.7V 1000mAh. Shows no magnetic properties. Type BL-5c. I add to 5V converter to drive the LCD.
Best regards Chris.

[epitopios]

Hi Damiafix
Bon Travail
Congratulations, great job.
After thinking I'd do a small change in the project, Carl.
1. Proposes to discard the R6 and give an additional 2.2 Kom parallel resistor between pins 14/13.
2. To improve the low frequency transmission Replace C7 ovens at 2,2mikroF.
3. Reduce the production of harmonics add a little bit about 1nF capacitor between R9-R10. .
4. For the "logic analyzer" experiments leave in its place. You can watch the logarithmic signal level measured!
It eats a lot of power but on the table is a big benefit.
Ready for a tour of the MAG will no longer need this analyzer.
Best regards Chris.

did you see better different from your Gradiometer with these changes ??
you have a 9 volt or 12volt/7Amh baterry ??
Regards , epitopios

[epitopios]

Hi Epitopios.
Whether your picture MAG Carl? ?????
And how goes the MAG EPE?
Where the cables go from the center of images (SLC007-AD557)?
You measure something?
Best regards Chris.

Hi Krzysztof
about MAG EPE: I send it to a friend , he is a good electronic and pc-man !!
I am waiting for some information .
cables: no-where ,.................
no measure there
Regards , epitopios

[epitopios]

Hi Epitopios,
many thanks for your reply! Yes, it's so strange....your gradiometer, work correctly?

All the best, D.

Hi guys , Damiafix and Krzystzof
unfortunatelly , i order another one which I have it already because the first one have problem , so better for a second one , I will try these days to make progress with the staff.
I watch your progress and i am impressed !!!
very hot days to stay inside , I hope you understand
Regards , epitopios

[Krzysztof]

Hi Damiafix
Bon Travail
Congratulations, great job.
After thinking I'd do a small change in the project, Carl.
1. Since the first 20dB signal distinction wrong, which means poor sensitivity to small signals.
Proposes to discard the R6 and give an additional 2.2 Kom parallel resistor between pins 14/13.
2. To improve the low frequency transmission Replace C7 ovens at 2,2mikroF.
3. Reduce the production of harmonics add a little bit about 1nF capacitor between R9-R10.
Opportunity to experiment. This gives a small low-pass filter.
4. For the "logic analyzer" experiments leave in its place. You can watch the logarithmic signal level measured!
It eats a lot of power but on the table is a big benefit.
Ready for a tour of the MAG will no longer need this analyzer.
Best regards Chris.