1k 1/4w resistor is ok as coolwin suggested.

Use  a 1/4 w, 1k ohm resistor should be ok as coolwin suggested.

The 1k resistor has Brown Black Red Gold (+/-5% or Silver +/-10%) for the color code. 

I measured a regular LED (2V , 20 mA, 5 mm in diameter, red LED, datasheet https://www.alliedelec.com/m/d/6355b8aba0b01578df0bb7b871ceefd7.pdf) with  a 12.4 V (constant Voltage) and 5A (constant cuttent) power supply, with this 1k resistor, the voltage drop on the red LED is 1.75 V, the current through the red LED is 8 mA.

5 mm LED of other colors (green, yellow etc.) should also be fine with this 1k resistor.

I haven't tried the flat LED, the 3rd on your picture yet. 20 mA 1.8-3.4 V (http://www.iled.com/class/INNOVAEditor/assets/YeniDatasheets/2715-2711(5mmkesikbas).pdf). But it should also be fine with 1 k resistor.

I don't have the first flat LED on your picture. There are some flat LEDs they use 5 V, 50 mA.

You used 360 ohm, 300 ohm and 300 ohm on the 1st, 2nd and 3rd LEDs (from the top down) on your picture (I assume the first color is Orange, not Red) is too small.

所有跟帖： 

• got it~ thanks -別在窗前等我- ♂ (997 bytes) () 05/16/2019 postreply 14:53:36

• where did you buy the yellow and white translucent LEDs? -xia23- ♂ (183 bytes) () 05/17/2019 postreply 04:01:49

• from ebay -別在窗前等我- ♂ (1922 bytes) () 05/17/2019 postreply 08:23:43

• kind of datasheets of 1W-100W High Power LED Chip COB Lights -xia23- ♂ (1433 bytes) () 05/17/2019 postreply 16:01:08

• Read my 悄悄話 please, use a 7812 voltage regulator on your LEDs. -xia23- ♂ (942 bytes) () 05/20/2019 postreply 04:19:10