LED Flickering on Mains
Rev x

**From reviewing your Photo, I misread 60-D-16R as 16Ω but in fact 391 is correct and \$16E\$ is upside down was my misteak 



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Plan C

Assuming 33 mA, 390Ω,  Vtot = 2.8V*4 + 390Ω*0.033A = 24.07V ...*0.033A= =0.8W

With 60mm pitch 10m yields ~165  in parallel or 165*0.8W/string = 132W max. or 13W/m or 24V@5.5A using a Laptop universal charger ( if you can find... usually all are 19.5 V now)

Old info from insufficient data and poor description for historical ruminance

Plan B ( based on poor specs)
- Measuring the Photo the 4LED + 16R , pitch is 60mm and total power @14V= 2.367W/m
 - Thus 24W per 10 m minimum.   cooler.
  -  Suggested Supply Tolerance 14V+/-0.2V  @ 2A min pref 3A
   - 12V will work but dimmer.



In order to smoothen the flicker let's do some calculations.


First you need a bridge rectifier to make rectified AC into DC.
Second , the decay time between 10ms pulses needs to attenuate 100Hz by at least 20dB or 10:1 in current to be significantly attenuate flicker.


if they did something like use 2 diodes to run 1 string in + and another on - then the flicker rate would be really bad at 50Hz.



So what value C is needed and at what cost?


I know that 10% ripple uses RC=8t and R=10~15 Ohms (approx)  per 65mW~100mW white LED.


For an RMS voltage of 220V , let's assume there are 330 LED's split into 5 strings of 66 in series or 5P66S with a Vf of 66*3V=198Vdc
the stripleds resistance when above 198V becomes 166*15R/5 ~500 Ohms
thus C=80ms/500 Ohms=160uF !! at >400V rating with a series drop resistor of 20V/(20mA*5P)=200 Ohms @ 2W



You can substitute your values and see if you want to retire it or rewire it  with a bridge , **cap, power resistor . have fun and get extra R in case it is too bright or too hot. The resistor must be flame proof and rated for line voltage.