A glance forward for voodoo

[h9361]

Before everything, i need to thank you Mr. Qiaozhi for your project.
In this topic, i am going to add GB to the project.
Before starting, first i request you to get me your suggestion and tell me your idea about my questions.
Finally i will test and try to fix the GB part and will tell you from my results.
I hope I can solve this issue with your help.
Thank you.

[h9361]

First Question about GB part.
Dear Carl,
please see the attachments, first is deferential integrator for original Voodoo and second is my primary preposition.
Please let me know your comments and corrections before practical testing.
As you know, my proposition is based SAT for each channel. Do you think it should be here too?
Thank you.

[h9361]

Since Mr. Qiaozhi explained about why he has used double-differentiated (double beep for ferrous metals ), maybe the schematic is better.
Dear Carl, is it possible to see the two suggestions and tell me which of them is logical?
Thank you.

[Qiaozhi]

Since Mr. Qiaozhi explained about why he has used double-differentiated (double beep for ferrous metals ), maybe the schematic is better.
Dear Carl, is it possible to see the two suggestions and tell me which of them is logical?
Thank you.

In a VLF detector with 2 channels, one is used for GB and the other for DISC. In the Voodoo Project the GB channel is replace by a PI. In this case you only need to implement ground balancing in the PI channel as you did with the Hammerhead circuit.

[h9361]

In a VLF detector with 2 channels, one is used for GB and the other for DISC. In the Voodoo Project the GB channel is replace by a PI. In this case you only need to implement ground balancing in the PI channel as you did with the Hammerhead circuit.

Thank you dear Qiaozhi for your comment.
I used the schematic with SAT in my Hammerhead. Do you think i should add the design (even with SAT) to Voodoo and start to my tests?

[Qiaozhi]

Thank you dear Qiaozhi for your comment.
I used the schematic with SAT in my Hammerhead. Do you think i should add the design (even with SAT) to Voodoo and start to my tests?

You don't need a self-adjusting threshold because the double-differentiating architecture will do the same job.

[h9361]

You don't need a self-adjusting threshold because the double-differentiating architecture will do the same job.

Thank you dear Qiaozhi.
Is the architecture true?

[Qiaozhi]

Can you post the schematic of the architecture that you used for Hammerhead?

[h9361]

Can you post the schematic of the architecture that you used for Hammerhead?

you can see it, some values is different.

[Qiaozhi]

In that case the schematic in post #7 should work.

[h9361]

In that case the schematic in post #7 should work.

Thank you dear Qiaozhi.
For GB part, i have an another idea.
As you know, A1(S1-S3) - A2(S2-S4) is GB. I remember that Mr. Carl said that we can use pulse width of S2 and S4 as GB pot, instead of A2.
If the method works, so we can add a extra option for Woodoo menu called GB.
In fact, the GB is pulse width sampling of GB channel (both S2 and S4).
For schematic, i connect the my GB channel (attached) output to pin4 from PIC18F4520.

Then i acquire GB reading (pin4-PIC) as pi_GB variable.
After that, we can subtract pi_target from pi_GB before checking threshold (Decide whether to beep or not, line 890 from code).
As a result, operator will do pump and increase GB value (GB channel pulse width) and check whether this machine is balanced or not?!

What do you think about the idea?

[Qiaozhi]

That could potentially work, but you will have to try it and find out yourself.
Personally I haven't found varying sample pulse widths to achieve GB as easy to implement as adjusting the gain.

[h9361]

That could potentially work, but you will have to try it and find out yourself.
Personally I haven't found varying sample pulse widths to achieve GB as easy to implement as adjusting the gain.

Thank you dear Qiaozhi for your help.
As you know, you have used a simple beep (not like normal PI which can distinguish surface or depth target, variable pitch and level) because of doing silence mode for Iron rejection.
But my purpose is not silence, i want to make a specific effect over audio tone.
Please see the attached, i use the schematic for my PI.


The question that arise here, do you have any suggestion for connecting pin6 of micro (Audio_EN) to the schematic for this purpose?
For example, as soon as detecting Iron, my audio part makes a different tone audio so that we can easily distinguish it's Iron.

[Qiaozhi]

The question that arise here, do you have any suggestion for connecting pin6 of micro (Audio_EN) to the schematic for this purpose?
For example, as soon as detecting Iron, my audio part makes a different tone audio so that we can easily distinguish it's Iron.

I have no experience with Miketv's audio mode, so I cannot give any advice. You will just have to experiment.

[h9361]

I have no experience with Miketv's audio mode, so I cannot give any advice. You will just have to experiment.

Thank you dear Qiaozhi.
Is it possible to guide me about values timer offset for GB_dly_offset and EFE2_dly_offset?
In your code, you defined as following:
const txon_offset = 4;
const txpd_offset = 8;
const main_dly_offset = 5;
const main_smpl_offset = 4;
const efe_dly_offset = 10;
const disc_dly_offset = 9;
const disc_smpl_offset = 6;

Do you think the following const is true?
const GB_dly_offset = 6;
const efe2_dly_offset = 11;

Thank you for your helping.