Signal loss?

ryanatunlock

New elf
Joined
Dec 19, 2018
Messages
20
I am trying to go live with my first little light show. Falcon F6v3 controller with a couple of Boscoyo 99 Candy Canes (100 pixel string, 12v).

All setup in the garage and working. When I put the candy canes out in the front yard they lit up but none of the sequencing effects worked, I just had static red and white lights on the candy canes.

After some troubleshooting I figured out that it was related to the cable length. I am using 2x 6m (Ray Wu) leads to each candy cane so total cable run is 12m.

Fortunately I purchased some null pixels even though I didn't really understand what they were for or how to use them. I connected the null pixel between the 6m cables. So I have falcon -> 6m cable -> null pixel -> 6m cable -> 100 pixel string.

Can someone help me understand and/or explain a better design?
 

daunce

Apprentice elf
Joined
Jun 9, 2010
Messages
91
Location
Ferntree Gully, VIC
Is it working now? What is the effect you are expecting?

I have a few runs of 14m 6 core security cable (1x data, 3+, 2-) from the F16v3 to first prop with no issues. The F16v3 has a good reputation for making it a fair distance to the first pixel.

So in the garage it was working using the same 2x 6m cables, or was it a shorter length?
 

ryanatunlock

New elf
Joined
Dec 19, 2018
Messages
20
In the garage it was working with a 50cm cable, same setup but swapped the 50cm cable to a 12m and the lights came on in a red/white stripe but it was static - not scrolling like I setup in xLights.
 

AAH

I love blinky lights :)
Community project designer
Joined
Dec 27, 2010
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3,483
Location
Eaglehawk
Check the voltage at the start and end of your prop if you can. 12m is a fair way but should be easily achievable with reasonably heavy cable. Meter the cables to confirm the correct pin connections as well.
 

ryanatunlock

New elf
Joined
Dec 19, 2018
Messages
20
Thanks AAH. I have just put together a volt ammeter inline with some ray wu pigtails so I can easily test the voltage now.
 

scamper

Dedicated elf
Joined
Jan 5, 2014
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1,081
Location
collie
If you put a null pixel in and it works, then the cable was too long for the signal to get through.
As Alan said, check for voltage drop. If you have a fair bit of drop on the voltage, you will also get drop on the data signal. Because the data signal is smaller, it doesn't take much to be too small to not work.
What a null pixel does, is takes the data signal and regenerates it so it is then large enough for the next pixel to see.
 
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