Bipolar PI design

[Carl-NC]

The 4066 has 14 pins, the 4316 has 16 pins. They are pin-compatible except for the 2 extra pins. You can use the 4066 in the Bipolar PI design but you will need to add level translators to the micro. I think that was previously discussed in this thread.

[GeoMax]

Hello Sayan1345,

what electronic design software are you using to design your PCB?

[sayan1345]

Hello GeoMax
proteus

[sayan1345]

Hello Mr Carl thank you very much
I couldn't find PIC16F18426
Can I use PIC16F84 instead of PIC16F18426?
also I couldn't find max412

[Laith]

In Bipolar PI Rev 2.1 build, using IRF9630 for Q1/Q2 and IRF740 for Q3/Q4. Since the PCB layout is very tight, is it mandatory to use heatsinks for all four MOSFETs? Will the heat build-up cause frequency drift or affect the threshold stability and ground balance during extended use?"

[h9361]

The TDI with the GB ON (at number 8 ) detects the nugget at 10 cm. The Bipolar PI with the GB off detects it at 3 cm, and with the GB potentiometer halfway through the range, right where the hot stone is rejected, the nugget is detected at 1 cm. I'm surprised that the TDI, with the GB in any position, doesn't lose depth for the 0.5 g gold nugget, and the Bipolar PI loses depth when changing the GB value. I understand that both detectors have subtractive GB, but in different configurations. I've tried modifying the GB on the Bipolar PI to match the TDI, and it doesn't work. There's no way to reject the stones. I've put a 1 Mohm potentiometer on the GB to get a good adjustment range, and it doesn't work either.
Any ideas, Carl?
I've attached the schematic of my circuit, the one shown in the video, in case it helps anyone.

Hello
Dear eduardo
I have a question about your schematic (audio part).
Is the P5 (threshold) connected to Ground and -5V?
Thanks

[eduardo1979]

Hello.
Yes, GND and -5V.

[h9361]

Hello.
Yes, GND and -5V.

Thank you.
I have another question, please forgive me.
Can you tell me why you use R74,C43 and R75,C44?
Is it for reaching a soft audio?

[eduardo1979]

There are many versions of the schematics posted on the forum. Please attach the schematic you're referring to so we can identify the specific components you mean.

[h9361]

There are many versions of the schematics posted on the forum. Please attach the schematic you're referring to so we can identify the specific components you mean.

Your schematic, attached.
Can you tell me why you use R74,C43 and R75,C44?
Is it for reaching a soft audio?

[eduardo1979]

Capacitors are used to filter noise. I don't see resistors R74 and R75 in the schematic.

[h9361]

Capacitors are used to filter noise. I don't see resistors R74 and R75 in the schematic.

See attached (red circle).

[Carl-NC]

These are the SAT circuits. Exact same thing as in Hammerhead.

[h9361]

These are the SAT circuits. Exact same thing as in Hammerhead.

Thank you dear Carl for your information.

[Badim49]

And this schematic above is just a "picture" too, for all those who are interested, here is the schematic file.
The software that is needed is "ExpressPCB",
(don't get confused, it's a free installation package that during installation also installs a schematic part called "ExpressSCH" in which I mostly draw schematics)
and you can download it free from here: https://www.expresspcb.com/
And here is the sch file:

There is a firmware ?