Full m/lab SD2000 schematics

[Geotech11]

Check if there is a frequency on the gate and drain of the mosfet transistor that enables the positive voltage of the 2n700 or that you put in, if the frequency exists it would mean that the mosfet is not working! There I also tried a bipolar transistor for example bc547 and I get 5v. The line that connects to the battery drop has nothing to do with the positive voltage! Maybe you have somewhere connected not to the mosfet that regulates 5v but to the line for voltage 5v? If something in the connection is faulty for example some component that is powered by the 5v line there will be no 5v voltage present at the output of the 2n7000 or whatever you are using at that location for that line or rail. I would remove the components from the pcb if you have a base and check the voltage, and if there is a voltage of 9.9v I would put back one component at a time and that way you can see which component is problematic or possibly there is a short circuit. Because of such problems that can occur when I solder components, I first solder the components that are in charge of powering the integrated circuits and only when I check and determine that there is normal power supply at the control points or lines, after that I solder the other components on the pcb.

Hello, thank you for your suggestions.
I have measured the 2N7000, and indeed, frequency signals are present on both its gate and drain. Could you give me a general idea of what might be causing the 2N7000 to malfunction? I measured the resistance across the +5V and -5V rails to be in the range of tens of kilohms, so there does not appear to be a short circuit. I have only soldered the components for the PULSE CCT, the SD2000 POWER SUPPLY AND REGULATOR CCT, and the LOW BAT CCT. In the PULSE CCT, the signal following the 10nF capacitor is a standard square wave; however, after passing through the 22k resistor, the waveform closely resembles a triangle wave. Is this normal?

[Orbit]

Check if there is a frequency on the gate and drain of the mosfet transistor that enables the positive voltage of the 2n700 or that you put in, if the frequency exists it would mean that the mosfet is not working! There I also tried a bipolar transistor for example bc547 and I get 5v. The line that connects to the battery drop has nothing to do with the positive voltage! Maybe you have somewhere connected not to the mosfet that regulates 5v but to the line for voltage 5v? If something in the connection is faulty for example some component that is powered by the 5v line there will be no 5v voltage present at the output of the 2n7000 or whatever you are using at that location for that line or rail. I would remove the components from the pcb if you have a base and check the voltage, and if there is a voltage of 9.9v I would put back one component at a time and that way you can see which component is problematic or possibly there is a short circuit. Because of such problems that can occur when I solder components, I first solder the components that are in charge of powering the integrated circuits and only when I check and determine that there is normal power supply at the control points or lines, after that I solder the other components on the pcb.

[Geotech11]

That they definitely have 100n on the positive and negative terminal according to gnd. And tantalum in some places.

N-channel MOSFET: PIN-D is connected to a 150 µH inductor, and PIN-S is connected to the negative terminal (-VB) of a 6V battery. Is this connection correct?

[Geotech11]

If the red connecting wires shown in the diagram are connected together, will this result in an abnormal +5V output?

[Geotech11]

The battery voltage is 6V. The low-battery detection circuit is functioning correctly; the LED flashes when the voltage drops below the threshold. The voltage measured between pins 2 and 3 of the LM336 is 2.5V. Test points at pins 2, 10, and 12 of the CD4093 measure a frequency of 62.5 kHz with a 50% duty cycle.

If the red connecting wires shown in the diagram are connected together, will this result in an abnormal +5V output?

[Geotech11]

Did anyone try this schematic ( i mean both - original and modificated) for errors? In a matter of educational purpose, did anyone make so that we know it really works?
Regards

The battery voltage is 6V. The low-battery detection circuit is functioning correctly; the LED flashes when the voltage drops below the threshold. The voltage measured between pins 2 and 3 of the LM336 is 2.5V. Test points at pins 2, 10, and 12 of the CD4093 measure a frequency of 62.5 kHz with a 50% duty cycle.

[Geotech11]

schematic was remade by Vladimir. enjoy

Hello! I encountered an issue while taking measurements: the -5V rail is functioning normally, but the +5V rail measures only around 0.1V. How should I go about troubleshooting to identify which specific section is responsible for the missing +5V?

[detectormods]

How about I put up the schematic for a design built with STM32 , ADC input, demods done inside the processor, auto ground balance, but I would need to get permission from the software engineer as it has adaptive filtering for emi.

[Orbit]

That they definitely have 100n on the positive and negative terminal according to gnd. And tantalum in some places.

[Geotech11]

https://youtube.com/shorts/zpMh56rB2...P00zKYWhw03HdI I played around a bit with adding discrilination on the sd 2000 both channels work fine here is channel 1 on the recording I spent most of my time on noise removal here no noise elimination plug and variable front circuit gain added.

Do the official circuit boards and chip power pins all have decoupling capacitors? I've noticed that schematics almost never include power decoupling capacitors like 100nF.

[Geotech11]

Thought i would share with you all the full schematics i made up for
the M/lab SD2000.Over the years with all the fiddling on the 2000
i did and the resulting hand drawn schematics,why not do the whole
thing and present it to those that have an interest.
I would like to give a special thanks to the people that helped me
identify some of the chips,with out there input many chips would
still be a mystery.
Drawing schematics is`nt my thing so i hope it looks ok,also i had
to present it in two parts because of the 1meg pdf limit.

Zed....

NOTICE FROM GEOTECH -- PLEASE READ
These schematics may contain design elements which are protected by US and/or Australian patents. Reproducing all or parts of this circuit may violate those patents. Any use of these schematics beyond the purposes of education or modifications to an existing SD2000 should be discussed with Minelab.

Do the official circuit boards and chip power pins all have decoupling capacitors? I've noticed that schematics almost never include power decoupling capacitors like 100nF.

[Geotech11]

I’m not sure whether NP0/C0G capacitors can be directly substituted for film capacitors

[Geotech11]

’ve gone through the comments several times — 66 pages in total — my eyes are almost worn out. I redrew the schematic based on ZED’s drawings and modified the battery level display circuit (CCT). I used a large number of MLCC capacitors and only a few film capacitors in certain sections. I’m not sure whether it will work successfully, but if it does, I will share the files. image widget

[Fazel]

Hi friends, can you email me the sd2000 or 2200 gerber files or pcb file??
[email protected]
thank you

[Orbit]

https://youtube.com/shorts/zpMh56rB2...P00zKYWhw03HdI I played around a bit with adding discrilination on the sd 2000 both channels work fine here is channel 1 on the recording I spent most of my time on noise removal here no noise elimination plug and variable front circuit gain added.