Julian: I have a nice, cheap 120-V. Walmart night light. But flicker is discernable in one's peripheral – not direct vision. Circuit is: Left plug prong -> [diode] -> [1/4-Watt 10,000 ohm 5% resistor] -> LED[o] -> switch -> right plug prong. Nice, warm 2700K light! Why is its flicker not terribly noticeable 60 Hz halfwave flicker? Is there microcircuitry in the [o] wafer? (It has 6 leads but I can't see where they go.) Squinting, I can see that the 3 mm orange-ish yellow dot has three little bright spots inside. I assume it is a phophorescent material excited from UV LEDs beneath. Perhaps that slows ON/OFF smoothing out flicker.
How can I eliminate ALL flicker? I want to mount this in our grandmother clock aimed down to illuminate the brass chains, weights and pendulum bob. Thank you. Robert USA
Just a side question concerning cob leds which consist of a bunch of series and parallel connected leds. I assume there is no on board resistors ? If so, isn't it a bad idea to parallel leds ?
Hello Julian, I'd like to buy a DC power supply like that "trusty" one you use in this video. Can you tell me model & where did you buy it from? thanks in advance!
Sorry if this has been asked before but its hard to find a clear answer. And it seems you're the man to ask! So I will purchase a suitable LED dimmer switch. And I had some standard 4 LED aluminium 'CREE' bulbs however the room was too dark and full of shadows. I am now hoping to purchase. SMD 30 * 5050 10W LEDs which came to have 1000lumens and 120° beam. Should I plunge for these. Or should I purchase a COB bulb?
Did you ever get that phosphor off and how did you do it?
What is the best Led GU10 from Aliexpress?
Are these COB LEDs more efficient (lumen/watt) than other LED bulbs?
Julian: I have a nice, cheap 120-V. Walmart night light. But flicker is discernable in one's peripheral – not direct vision.
Circuit is: Left plug prong -> [diode] -> [1/4-Watt 10,000 ohm 5% resistor] -> LED[o] -> switch -> right plug prong.
Nice, warm 2700K light! Why is its flicker not terribly noticeable 60 Hz halfwave flicker?
Is there microcircuitry in the [o] wafer? (It has 6 leads but I can't see where they go.) Squinting, I can see that the 3 mm orange-ish yellow dot has three little bright spots inside. I assume it is a phophorescent material excited from UV LEDs beneath. Perhaps that slows ON/OFF smoothing out flicker.
How can I eliminate ALL flicker? I want to mount this in our grandmother clock aimed down to illuminate the brass chains, weights and pendulum bob. Thank you. Robert USA
Just a side question concerning cob leds which consist of a bunch of series and parallel connected leds. I assume there is no on board resistors ? If so, isn't it a bad idea to parallel leds ?
Hello Julian, I'd like to buy a DC power supply like that "trusty" one you use in this video. Can you tell me model & where did you buy it from? thanks in advance!
do you show somewhere how to build the power supply you use in that video? it looks pretty neat and i'd rather build one than buy one…
The cob grow light technology is impressive to say the least. Can't wait to see how soon the rest of the led grow lighting industry adopts it.
Are these cobs cheap enough to build a led grow light using maybe 10 cobs to make a grow light😳😳😳😳
I see 10 LEDs
why not try smd led? i think aluminum cob led do not have better heat dissipation than smd led
do you know if you can cut COB strips? I have an LED cob strip thats slightly too big
Sorry if this has been asked before but its hard to find a clear answer. And it seems you're the man to ask! So I will purchase a suitable LED dimmer switch. And I had some standard 4 LED aluminium 'CREE' bulbs however the room was too dark and full of shadows. I am now hoping to purchase. SMD 30 * 5050 10W LEDs which came to have 1000lumens and 120° beam. Should I plunge for these. Or should I purchase a COB bulb?