Hello, I am fairly new to electronics and I try and be as respectful as possible when it comes to asking a question on the forum. I have noticed as a new member that SOME elder member gives disrespectful, condescending remarks for no apparent reason and really discourages me from asking questions and learning. Here is a question I posted just yesterday with the title "beginner circuit question"
(tell me your opinion on whether he was giving advice or just being rude and disrespectful)
"A series resistor is not necessary if the voltage can be regulated to match the LEDs (Vf). One way to do this is to match a battery to the LEDs. If your LEDs forward voltage is 1.2v, you can string ten of them (10x1.2v=12V) and power them from a 12v battery and not need a series equivalent resistor.
My question is how would you calculate the math for resistance and current when there is no resistor. Thank again for the help
raschemmel -commented my post with
That's the dumbest idea I've heard in a long time, mainly for the reasons already indicated but given the post title "Beginner Question it is completely appropriate. On the other hand, one might easily conclude "You're a beginner and ALREADY too lazy to use a resistor !?"
Try to spend your time more wisely.
This is someone with 35yr experience talking down to some who has maybe a year under my belt!
Don't be so thin skinned. You have people with decades of experience in electronics and programming offering you free advice on any question you want to ask. Even at the cost of an occasional rude comment you're still getting a tremendous bargain. When you break forum rules, such as by cross posting, we consider that quite rude and you can expect the same treatment in return.
I'm inclined to think it is a dumb idea also. What happens if one of the LEDs has a threshold of 1.19v ? Or if one of the LEDs has a threshold of 1.21v? Or if the power supply output is actually 12.1v?
A diode is like a weir in a river. if the water level is below the top of the weir no water flows. If the water is higher than the top of the weir there is no limit to the flow rate.