Random flicker in 8th out of 13 boards in a series.

[dilgod]

Hi guys,

I have a wierd problem. I have 13 boards (a mix of V3, V4 and V5 boards). One of the V3 boards started acting up today in the middle of a show.    It is the 8th board in the series. This board worked fine last year.

When I remove the cat 5 cable and run the tests, the lights turn on sequentially. Once I plug in the Cat5 cable, and power up the board, all the lights start flickering randomly - including the 7 segment display on the board. All the 3 7seg display do not display the channel numbers or the words PRG TST etc correctly during startup with the Cat5 cable plugged in. The mode button does not switch to test mode. When the cat5 Cable is removed and the power reset on the board, the board behaves normally.  What could be wrong? Luckily I have a spare board for the show to go on... I am afraid if another one starts acting up, I am toast. Help needed.

All other boards are working fine - while still connected to the one that is playing up.
Dilip

[magic8192]

I may not be much help, but I had flickering problems last year and my resolutions were as follows: I resoldered the triacs  to fix one, replaced the pic in one and reflashed the pic in another. 

[dilgod]

I have a spare pic and I can try to replace it and see. Will the V5 pic be compatible with the V3 pic?

Also, it was working for 10 whole days this year and last night it started misbehaving - but ONLY with the cat 5 cable plugged in.  The full load of the lights is also plugged in.

Any other pointers.

[memphislights]

try changing circuits where the LE is plugged in.

if leds, do you have snubbers.

look for cold solder joints.

if temps are below 37f, it could be a temp related issue for the 3.3V regulator.

[dilgod]

Came back from work just now and the board is working like nothing was wrong.
It looks like the temperature has some affect on that board. It was baking in the sun till now.
(Some nights the temperature is around 33-34 F)

I will replace the 3.3V regulator, as soon as I can (over the weekend)

Thanks for your help.

[memphislights]

Replaced the 3.3v regulators earlier this year in all of the v3 and v4 LEs that we had, but still had temp issues in about 6/12 of them.

2x c7 or c9s in the box placed near the regulators should keep it warm enough to run into the teens.

If you want to test out the temp theory, when you see odd behavior on an LE, warm up the regulators with a heat gun and see if it gets better.

[dilgod]

I will try out the theory of the heat gun... (might use a hair dryer instead).

If it does do the trick, how do I permanently fix the issue (apart from pointing the hair dryer during the display)? Is there a permanent solution?

[RJ]

Replaced the 3.3v regulators earlier this year in all of the v3 and v4 LEs that we had, but still had temp issues in about 6/12 of them.

2x c7 or c9s in the box placed near the regulators should keep it warm enough to run into the teens.

If you want to test out the temp theory, when you see odd behavior on an LE, warm up the regulators with a heat gun and see if it gets better.

What where you replacing them with. Should be the ones I sent out and they should not behave like that. They are rated to -40c

RJ

[wbuehler]

That sounds a bit odd.

I replaced 8 of my 3.3V LE Regs, with the provided replacements, and have had no issue running them in the teens.

[memphislights]

They were the regs that I got from RJ in the spring.  The "heater" seems to be a pretty solid workaround for us, so we are not going to worry about it.  All of the V5s seem to be doing well.