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Electronics for Audiophiles: Voltage and Current (Video)

amirm

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I am starting a new educational series on simple but essential engineering concepts/lingo we use in discussing audio products. This is the introductory video on voltage, current and power supplies:


Please give feedback as to whether you find this type of video useful and I will make more of them.

Thanks.
 

Zoomer

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+1
 

DanielT

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Thanks for the video Amir. Pedagogically well done.:)

You start talking about AC/DC and High Voltage. It's impossible not to to paste::D


51lcSGjzc0L.jpg
 

nyxnyxnyx

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thank you Amir. Just about time I need to refresh and validate my knowledge while learning more :)
 

tomtoo

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To be honest iam not so happy with the video.

I think it would be better to stay for the first video just with voltage, current and resistence. Its not right that the voltage kills you, its the current through you body that kills you. That you can thouch 24V is coused by your high body resistence, that limits the current. Understanding how voltage, current, resistance interact is the A in the abc. I know that sounds like critisism for nothing. But its so importend imo to get it right from the beginning. Static has a very high voltage but does not kill you, couse it delivers not enough current.
 
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amirm

amirm

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Its not right that the voltage kills you, its the current through you body that kills you.
No, it is right for this type of video and context. Touch a high voltage source and you risk electrocution. Touch a low voltage source and you are fine. Touch a high current/low voltage source, and again, you are fine. Anyway this is a side comment so not sure how it became the core of your criticism.
 

tomtoo

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No, it is right for this type of video and context. Touch a high voltage source and you risk electrocution. Touch a low voltage source and you are fine. Touch a high current/low voltage source, and again, you are fine. Anyway this is a side comment so not sure how it became the core of your criticism.

Its the basics that your internal resistance determines the current if not the resistance of the voltage source determinse it. Its just one littel step to get it right from the beginning. So you start with its the voltage that kills. And you and i know thats not how it is. Its not good imo to start with voltage and current. It should be voltage, current and resistence. Its ohms law, it has 3 letters.
 

maty

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I am starting a new educational series on simple but essential engineering concepts/lingo we use in discussing audio products. This is the introductory video on voltage, current and power supplies:


Please give feedback as to whether you find this type of video useful and I will make more of them.

Thanks.
Education from experts always useful. Extremely welcome.
 

F1308

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Its the basics that your internal resistance determines the current if not the resistance of the voltage source determinse it. Its just one littel step to get it right from the beginning. So you start with its the voltage that kills. And you and i know thats not how it is. Its not good imo to start with voltage and current. It should be voltage, current and resistence. Its ohms law, it has 3 letters.
I was told the real thing killing you is a given amount of current reaching your heart.

From that basic point it goes that a little voltage applied directly on flesh (very low resistance) being exposed through a cut in the skin (high resistance) could certainly kill you.

Since high voltages can overcome the resistance skin have, the general idea people do remember is only high voltages are dangerous.
 

Lambda

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ouch a low voltage source and you are fine. Touch a high current/low voltage source, and again, you are fine
Because there is no(low) current flowing trough your body if you touch a low voltage source that can deliver high currents.

Also not all Powersupply's are Voltage sources with battery chargers and LEDs current limited powersupply's are typical.

And to low voltages can defiantly also cause damage.
if the device needs the same Power current goes up if voltage goes down.
if current goes up Resistiv loss goes up = heat goes up.

Also Duty cycle on DCDC converters goes Up or Down (depending on buck or boost)
If the Duty cycle is to low or high the bootstrap capacitor won't fully charge or discharge to mush and the Highside fet will blow up

If the supply voltage is also the Mosfet gate voltage in a DCDC converter with to low voltage switching time goes up and internal resistance. maybe killing the mosfet.
 
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