Not sure if that would be considered protection.

Maybe it's really a diode tester or a hand warmer...

 

While a series diode is a poor choice in a battery powered system you may want to provide some sort of reverse voltage protection, otherwise one time putting the batteries in backwards will brick your circuit.

This is a good place for a MOSFET used as reverse protection device, if you can get one with a tiny Vgs on voltage.

 

The next time you see such a poorly drawn schematic, make a note of the source, ignore it, and never use information from that source again.

Unfortunately, the web is filled to the brims with such sites.
The problem is not constrained to electronics. It affects every area of human-interest spectrum.

 

Unfortunately, the web is filled to the brims with such sites.
The problem is not constrained to electronics. It affects every area of human-interest spectrum.

I apply the same methodology for everything on the WEB.

I have relatives who get their news almost exclusively from Facebook. I have never done Facebook and never will; that's a complete waste of time and bandwidth...

 

Where did you find that nonsense?

If we assume that the inductors are being used as chokes, you wouldn't need the one on the negative battery terminal. You also wouldn't need the one on the positive terminal. If there was any noise, preventing it from affecting the power source would be the least of your concerns.

If we assume that the parallel capacitors were for decoupling, they would offer better suppression if they were placed near components that were either generating noise, or could be affected by it.

The next time you see such a poorly drawn schematic, make a note of the source, ignore it, and never use information from that source again.

Sorry I didnt save the web, just took note of the circuit as many other things I note, next time I will be more careful about the source

I totally agree with you about the decoupling capacitors, there would offer good suppression when placed as close to the IC as possible.

About the inductors, I think that they could be there because of EMI as far as they were talking about RF noises in a radio system. I will try to find the source just for the reference


Thank you,

 

Sorry I didnt save the web

Browser history??

just took note of the circuit as many other things I note, next time I will be more careful about the source

It's common courtesy to give attribution for intellectual property that isn't your own.

 

Crude drawings aside, you could keep the diode and use a self resettable fuse in series with the battery. And I agree that the choke inductors have no point in that position.