Author Topic: how do you test the 4 pin LDO for the Aether II colors?  (Read 205 times)

Offline arw01

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Think a wiring error when I changed from cat 5 pigtails to a 4 wire Ray plug fried the red LDO regulator.  But before I remove it and put in a new one, wondering what the troubleshooting method is for one of them with a multimeter?

LM2941T/NOPB

is the Manufacturer part

Offline tbone321

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #1 on: November 06, 2017, »
Why would that happen?  There should be no connection there.  The Cat 5 connector should only be connected to the RS485 to send data to the device and the only other connector should be for 16 VAC to the bridge rectifier to power the unit.  What changes were you making to the wiring?
If at first you don't succeed,
your not cut out for sky diving

Offline arw01

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #2 on: November 06, 2017, »
Why would that happen?  There should be no connection there.  The Cat 5 connector should only be connected to the RS485 to send data to the device and the only other connector should be for 16 VAC to the bridge rectifier to power the unit.  What changes were you making to the wiring?

There are 4 wires that come in, crossing a ac line with a data in line..

Blue, White, and Green all function.  Red comes up with white off the top of my head.

Offline JoeFromOzarks

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #3 on: November 07, 2017, »
One would think that if the AC was connected to the DMX input, the RS485 chip would toast, not smoke a LM2941 regulator.   (I don't have a schematic to verify, but it seems logical.)  Connecting a DMX signal to the AC in wouldn't toast a regulator LM2941 either.

Sounds like a tad bit more troubleshooting is in order.

:) joe




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Why would that happen?  There should be no connection there.  The Cat 5 connector should only be connected to the RS485 to send data to the device and the only other connector should be for 16 VAC to the bridge rectifier to power the unit.  What changes were you making to the wiring?

There are 4 wires that come in, crossing a ac line with a data in line..

Blue, White, and Green all function.  Red comes up with white off the top of my head.
« Last Edit: November 07, 2017, by JoeFromOzarks »
"If it was easy, everybody would be doin' it!!!"        :)

Offline arw01

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #4 on: November 08, 2017, »
I was thinking of the RS485 fried it would not respond to well, but all colors are fine except the red does not come on alone. 

I was trying to find a pin out for the LDO, but only found the chip package one off the Mouser link.

Will check the PIC tonight, bought a spare just in case with a spare LDO. At $90 a light, it is worth pretty extreme work to fix it.

Offline tbone321

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #5 on: November 08, 2017, »
I would also check the connections on the LED and make sure that there are no cold solder joints or broken wires.  Be sure to check on the board as well as the LED.
If at first you don't succeed,
your not cut out for sky diving

Offline arw01

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #6 on: November 09, 2017, »
Personally never had a cold solder joint.

Replaced the RS485 today just because and no change, am working on getting Pickit 3 going with Windows 10, and that is a "treat" so far!

Offline arw01

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #7 on: November 11, 2017, »
Re-programming the pic chip did not solve.

What ultimately became the solution was when I busted off the data leads (white orange and white wire type data leads) and started chasing those down to make sure I had them correct.

Turned out when I made the initial error of getting the ac crossed up, I had also messed up the other signal wire that would have carried the other side of the differential signal.  Basically I had 2 + differential lines and no connected - differential line.

After some pulling of snipped pigtails and soldering in tight spaces I believe I have a functioning Aether II again and will be putting it back into its shell in a few hours.

Offline tbone321

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Re: how do you test the 4 pin LDO for the Aether II colors?
« Reply #8 on: November 11, 2017, »
Glad to hear you got it working.  I have about 6 or 7 of those to build yet.  I finally got around to building the 3 original Aethers I have.  They worked well for Halloween but do have some minor issues.
If at first you don't succeed,
your not cut out for sky diving