Dear all,
could you please help me with this? i am building the F5 clone and have soldered everything less the resistors and the LEDs for the f5 boards and the PSU unit from diyAudio. i bought a LED and resistor kit and the resistors there are up to 820ohms only for 12v DC. In the build, it says that the resistor should be 15k. I presume the voltage for the F5 board is only 18v DC right? Why is the resistor value so high and could i get away of using what i have or do i need to buy new ones? Thank you Philip
could you please help me with this? i am building the F5 clone and have soldered everything less the resistors and the LEDs for the f5 boards and the PSU unit from diyAudio. i bought a LED and resistor kit and the resistors there are up to 820ohms only for 12v DC. In the build, it says that the resistor should be 15k. I presume the voltage for the F5 board is only 18v DC right? Why is the resistor value so high and could i get away of using what i have or do i need to buy new ones? Thank you Philip
rule of thumb: 1K per V of rail where you want to connect
regular small size resistor is generally enough, call it 250mW or more
if too bright, increase value
example - 22V5 rail (common FW format) - use anything between 22K and 27K - whatever you have in drawer
and,yes, you can connect resistors in series, if needed
regular small size resistor is generally enough, call it 250mW or more
if too bright, increase value
example - 22V5 rail (common FW format) - use anything between 22K and 27K - whatever you have in drawer
and,yes, you can connect resistors in series, if needed
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hi - I am sorry for my ignorance but why then do I have an led which is 12v with a kit resistor of <1k? is it a special led?
i bought this kit to build something for my kids many years ago and i thought i could still use it
S093 LED-creative-set
We just made guacamole. The recipe called for three jalapeno peppers. Being mellow people, we used less.
LED brightness is the same way. Some people like their LED HOT. Others are happy with dim.
LEDs have improved a LOT over the years. Say the recipe was tested with stale peppers, and say we had fresh high Scoville zingers.
Decades ago, 12V and 500 Ohms was not too bright for office machinery.
Today, 12V and 15k (15,000 Ohms) is sometimes too bright for home or dim stages.
If you have a 820 in hand, try it tacked-in, but don't be staring at it when you switch-on. (I recently did that with a large LED and had eye-spots all day).
If you have a 15K in hand, try it. It may be bright enough for your listening room.
Not knowing the LED or the room, but a "recent" LED, I'd start with anything 2k to 10k, whatever I had too many of. (The electronics dabbler eventually ends up with dozens of every value except one critical need. The LED is not critical so can use anything close. Try higher/lower to taste.)
LED brightness is the same way. Some people like their LED HOT. Others are happy with dim.
LEDs have improved a LOT over the years. Say the recipe was tested with stale peppers, and say we had fresh high Scoville zingers.
Decades ago, 12V and 500 Ohms was not too bright for office machinery.
Today, 12V and 15k (15,000 Ohms) is sometimes too bright for home or dim stages.
If you have a 820 in hand, try it tacked-in, but don't be staring at it when you switch-on. (I recently did that with a large LED and had eye-spots all day).
If you have a 15K in hand, try it. It may be bright enough for your listening room.
Not knowing the LED or the room, but a "recent" LED, I'd start with anything 2k to 10k, whatever I had too many of. (The electronics dabbler eventually ends up with dozens of every value except one critical need. The LED is not critical so can use anything close. Try higher/lower to taste.)
I like blue for the same reason, it’s reminiscent of Cherenkov radiation -
Cherenkov radiation - Wikipedia
Cherenkov radiation - Wikipedia
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