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LED Christmas lights - love 'em or hate 'em?
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tom66:
Generally, I like them, but I find the multicoloured ones fairly tacky.  The warm white ones are pleasant;  not sure I like the cold or cool white ones at all. 
25 CPS:
I'm curious, does anybody know what the utility companies position on LED lighting is?  I remember reading about a 1970s TV regulated power supply circuit that introduced a nonlinear current waveform that caused some issues in places where it was in common use at the same time of day so I was wondering if LED lighting, Christmas or otherwise, being a nonlinear load has been a problem or at least something that's noticeable from the electricity utility end?
Red Squirrel:

--- Quote from: james_s on November 27, 2020, 09:27:35 pm ---I've never seen retrofit bulbs sold, but there is nothing stopping you from installing ordinary LEDs and then add a suitable current limiting resistor or proper constant current power supply to each string, ready made LED mini lights usually just have a resistor in series.

How many bulbs are in each segment? 20 used to be common but now most are 35 or 50 using 3.5 and 2.5V bulbs respectively so the 6V bulbs required for the 20 light segments are somewhat difficult to find. Things are complicated by the fact that some bulbs use more current than others so you may replace a 3.5V bulb with another 3.5V bulb and find that it runs high or low, throwing off the voltage on the rest of the bulbs in the string. I usually wait until right after Christmas and then buy up a bunch of bulbs at steeply discounted prices and then in my vintage strings I'll replace all the bulbs in a segment if the spares I have don't perfectly match.

A light dimmer set at 80-90% will dramatically increase the lifespan of incandescent lights for only a modest penalty in apparent brightness.

--- End quote ---

Hard to tell because of how they are built into the tree, my guess is like 25.   And yeah I would not be against altering the voltage, just can't seem to find actual replacement bulbs that are LED.  I think through hole LEDs would maybe work but those are not bright at all as they are only really meant for indicators.

Never thought of adding a dimmer I suppose that may be an option to make them last longer.   And yeah with a diode I would see the flicker.   I have some LED lights in there too just to add some colour and I run them off rectified mains so the flicker is not as bad.    Tempting to throw in a capacitor but I feel the lights may not like that as they are probably not designed to run at full duty cycle.
andy2000:

--- Quote from: Red Squirrel on November 27, 2020, 09:00:44 pm ---... Also, can someone explain this one?  If I put a 12v rated bulb, it dies immediately, while the 3v one does not.  Why would the higher voltage one die when the lower voltage one does not?  Since I did not know the voltage originally I figured I would start with highest and work my way down but that did not quite work!

--- End quote ---

That's because with series string lights, the current draw of each bulb is critical.  If you put 12v 100 mA bulb in a set designed for 3v 200 mA bulbs, the 12v bulb will see roughly 24v and blow instantly.  It's actually worse than that because the other bulbs never receive enough current to light up, so their resistance is a lot lower than when they are operating, so the 12v bulb probably sees close to 120v.   Higher voltage bulbs are usually lower current so that the power for each bulb stays reasonable. 

I generally measure the current draw of the bulbs in my lights sets and write it on the plug.  I also sort my spare bulbs the same way.  The best place to get spare bulbs is from other light sets.  For longest life you need to replace bad bulbs immediately.  If more than a few blow, the other bulbs see excessive voltage and fail quickly. 
themadhippy:
funny Ive never really noticed the flicker with incandescents

--- Quote ---Never thought of adding a dimmer
--- End quote ---
Best to check your chosen dimmer will play nicely with the load,if theres not enough you can get  very noticeable flashing
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