Can this string be repaired?

[DILA]

I am new to pixels, so not sure how to proceed. I have tested about 20 Paul Zhang 12v ws2811 100ct resistor strings and this is the first one with a problem. The first 20 pixels respond correctly, then it repeats red, green, blue, white, dead for the last 80. I turned off test mode in FPP and the first 20 went off, rest stayed on with the same pattern, almost I did get some purple. Powered down Kulp16 and when back on now only first 20 pixels respond. Tried another string on same port and port is fine. Any ideas on whats wrong? If its just a bad pixel I'll cut it out instead of the hassle of getting one string replaced.

thanks

Bob

[angus40]

You have nothing to lose by cutting out pixel #21 and reconnecting pixel # 22 to pixel # 20.
I would make the connections here temporary just to confirm #21 is the culprit.
It could be pixel # 20 is not passing the data to pixel # 21

Some folks just chop out the last working pixel and the first not working pixel as a quick solve ,but I like to save the last good pixel if it is not the issue .

[pakeonoahu]

I believe Paul Zhang keep pixels at Amazon warehouse, contact him and you should get a replacement fast, I made purchases from him in the past, so as my cousin did this year, Paul will make it right especially you have a bad string.

[MartinMueller2003]

Normally I cut out the last working and first non working pixel. You dont know if the issue is that the last working pixel is sending garbage or that the first non working pixel is actually broken.

[Barnabybear]

Hi, to be most efficient and keep joints to a minimum. If 20 works and 21 doesn’t, cut the string between 20 and 21, then attach 21 to your data. If 21 works then 20 is at fault and can be removed, if 21 doesn’t work then it can be removed.

[rayhjr]

You said you were new to pixels and the question of how to repair has been answered. My advice to you is if you're going to have pixels, then at some point your going to have to make repairs, get use to it. Whether or not you choose to repair or ask for a replacement is entirely up to you.
It depends on when I find a problem pixel as to how I go about repair. I keep solder sleeves, and those 3m push on crimps on hand for a "show is running make a quick repair and take out last working one and first not working one" and keep things running.
If I'm on the bench testing them I'll find the problem as described about and just remove the bad one and solder it in and heat shrink.
Some people don't like even cutting a few extra off a prop just do they don't have the added splice, and that's fine if that's how they want to do thing. But somewhere down the line removing a bad pixel is going to have to happen. Might as well get into the habit if knowing how to find it and repair it.

[dirknerkle]

Ray made some salient points! I'll add another.

Your time has value. You alone have to determine whether it's worth your time to repair strings when they go bad. Having the extra parts is worthwhile, but sometimes, the amount of effort required to make things right can become heroic -- in both the initial diagnosis and the eventual repair. Sometimes, the fastest and most sure fix is just to replace the darned lights.

Another sure-fire fix is to unplug them for good.

[MartinMueller2003]

Another sure-fire fix is to unplug them for good.

Nooooo. Dark is bad

[DILA]

You said you were new to pixels and the question of how to repair has been answered. My advice to you is if you're going to have pixels, then at some point your going to have to make repairs, get use to it. Whether or not you choose to repair or ask for a replacement is entirely up to you.
It depends on when I find a problem pixel as to how I go about repair. I keep solder sleeves, and those 3m push on crimps on hand for a "show is running make a quick repair and take out last working one and first not working one" and keep things running.
If I'm on the bench testing them I'll find the problem as described about and just remove the bad one and solder it in and heat shrink.
Some people don't like even cutting a few extra off a prop just do they don't have the added splice, and that's fine if that's how they want to do thing. But somewhere down the line removing a bad pixel is going to have to happen. Might as well get into the habit if knowing how to find it and repair it.

I started with building a grinch 15 years ago so no problems with cutting and repairing wires. My newbie status is in understanding the data and power flow in the strings. Yesterday 20 pixels worked 80 acted crazy, turn power off and on and 20 work 80 dead. I powered them up today and first 69 working, 70 dead, 71 constant red and the next 29 dead. After 5 minutes 69 working pixels, 70 turned on white, 71 still red and next 29 dead. 2 minutes later all 100 started working correctly. Could it be cold solder joints around pixels 20,21 and 69,70 causing this? I really don't want to return the string to Amazon, it has been a royal pain with shipping, it started when 2000 pixels were "undeliverable" 2 weeks ago and it hasn't got any better since.

thanks

Bob

[MartinMueller2003]

I would replace 20/21 and the restart testing. FYI: Anything you see after a 'bad' pixel is random garbage. After 20/21 are replaced, watch for the next point at which the pixels are not behaving and replace those.