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Watch out for Greatleds


plasmadrive

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Dear All,

Sometime back I found what I thought would be a great company to deal with...(they were until it went sideways) and a great product to buy.. Pixel strings with 6803 chips. The build quality was pretty good but they flicker badly. Turns out that as near as my engineer can tell, they have the PWM driven from the clock and not internally which means that none of the controllers we normally buy will run them correctly. They will flicker something awful except at full on.

After spending hundreds of dollars on samples as well as hours and hours of time by us, the company Greatleds will not make good on them. The price may have seemed ok, but they simply WILL NOT WORK with the controllers we all use.. as least the ones I have found.

This TOFT is on me. Stick with who we know!

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How were you trying to use them?

A sandevices 681 controller, or similar (j1sys) will run them just fine, assuming they are your standard 6803 pixel string.

Were you trying to run them with a standard DC controller?

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I tried them on a 6803 controller.. actually two of them.

The problem my programmer seems to think it is, is that they don't use internal PWM but rather the PWM freq is tied to the clock so you have to feed them a continuous clock or they flicker badly. Most controllers he tells me don't do that.. as a matter of fact, we could not find one that did.. We only tried 3 or 4 though.

I have not however tried the sandevices 681 controller you suggested. I have moved to other pixel strings and they work just fine on the 6803 controllers we are using..

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6803 are 5 bit pixels anyway, so they are not going to perform as well as 2801s, 3001s, etc. There are a few work-arounds, but at the end of the day, if you are doing anything pixel-intensive, its worth looking at the 2801s or 3001s.

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You are correct.. after these guys flaked I went to the 2801s from Ray Wu.. mucha mo betta!

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This is the wrong forum for this reply, but it is in The Coffee Shop, so I guess it is okay.

How many LEDs are you trying to drive? If the count is high enough, the voltage drop could be significant enough to cause the flicker. The voltage drop will be maximum when all three LEDS on each node are on. To the best of my knowledge no nodes have onboard clocks for the PWM because it would increase the cost of each node. I could be wrong as my knowledge is limited to only a few pixel series.

It could be your wire diameter or even your power supply capacity too.

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A link to the 6803 pixels may help to determine what these may actually be. Can you give us the link so i can take a look

Thanks

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"How many LEDs are you trying to drive? If the count is high enough, the voltage drop could be significant enough to cause the flicker. The voltage drop will be maximum when all three LEDS on each node are on. To the best of my knowledge no nodes have onboard clocks for the PWM because it would increase the cost of each node. I could be wrong as my knowledge is limited to only a few pixel series.

It could be your wire diameter or even your power supply capacity too."

While I appreciate all the input trying to help me fix the problem, (we have done a lot of tests and our conclusion is as I stated), that was really NOT the reason for the OP. I wanted to warn everyone about the company itself.... not seek a fix for their product. I have done my bit to put up the red flag from my experience.. salute or not, it is up to everyone individually.

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plasmadrive wrote:

"How many LEDs are you trying to drive? If the count is high enough, the voltage drop could be significant enough to cause the flicker. The voltage drop will be maximum when all three LEDS on each node are on. To the best of my knowledge no nodes have onboard clocks for the PWM because it would increase the cost of each node. I could be wrong as my knowledge is limited to only a few pixel series.

It could be your wire diameter or even your power supply capacity too."

While I appreciate all the input trying to help me fix the problem,  (we have done a lot of tests and our conclusion is as I stated),  that was really NOT the reason for the OP.  I wanted to warn everyone about the company itself.... not seek a fix for their product.   I have done my bit to put up the red flag from my experience.. salute or not, it is up to everyone individually. 


Is it really that difficult to post a link? The people who are responding to this thread have been using pixels for a while and know a great deal about doing it the wrong way! Pixels can be very finicky. Chances are very good that you didn't even get the right chip to begin with. Hey, what do I know, I don't have my own engineer!
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Guest wbottomley

plasmadrive wrote:

Dear All,

Sometime back I found what I thought would be a great company to deal with...(they were until it went sideways) and a great product to buy.. Pixel strings with 6803 chips.  The build quality was pretty good but they flicker badly.  Turns out that as near as my engineer can tell, they have the PWM driven from the clock and not internally which means that none of the controllers we normally buy will run them correctly.  They will flicker something awful except at full on.

After spending hundreds of dollars on samples as well as hours and hours of time by us, the company Greatleds will not make good on them.   The price may have seemed ok, but they simply WILL NOT WORK with the controllers we all use.. as least the ones I have found. 

This TOFT is on me.  Stick with who we know! 



Do you have a link to the LED's you're talking about?
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Is it really that difficult to post a link? The people who are responding to this thread have been using pixels for a while and know a great deal about doing it the wrong way! Pixels can be very finicky. Chances are very good that you didn't even get the right chip to begin with. Hey, what do I know, I don't have my own engineer!

I didn't post here to advertise for that company.. only to warn you about how they do business when something doesn't go quite right. The actual product was not really that relevant to my post... so, no link..

I am an electronics engineer and I have a software engineer that works with/for me.. and I assume we have a clue what we are doing... (hopefully) Especially since architectural LED art systems are part of what we do... So chances are we got the right chip to begin with...

I posted the info I wanted to post to warn others.. Can't really see any need to discuss it further.. like I said earlier, salute or not.. it's up to you..
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edvas69 wrote:

A link to the 6803 pixels may help to determine what these may actually be. Can you give us the link so i can take a look

Thanks

I think you posted this while I was answering Al In Raleigh.. didn't see it till just now. Anyway, I am not interested in advertising for these guys.. Like I posted a few minutes ago, it was a warning about the company, not to inquiring about help with the parts.

Thanks anyway for the concern..

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IMHO, I didn't see anyone asking for advertising here. Just more info so they could have helped you.

FYI... If there is anything that I have learned being a software guy it's that even 2 well trained people can be wrong sometimes. You should NEVER feel insulted when people offer to help, even when you believe yourself to be a master in your field. Being in the field for nearly 30 years (first person who makes a punch-card joke is going to be smacked), a single day has not gone by where someone didn't teach me something.

The people that posted were trying to help in their own way. They can't help you get your money back, but they could have helped to salvage what you already have invested.

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Guest wbottomley

All we asked for is a link to the product you are bashing.

Two reasons why one is not being posted...

1) You ordered the product and not reading the full description

2) You're shifting the blame for a small mistake


If this type of pixel is something not currently supported by the latest hardware, one of those providers might be able to solve the problem. Until then, I'm ruling this out as operator error until I can see more evidence.

I'm basing an opinion on what has been presented before me. Without the company and product information... it is what it is.

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wbottomley wrote:

All we asked for is a link to the product you are bashing.

Two reasons why one is not being posted...

1) You ordered the product and not reading the full description

2) You're shifting the blame for a small mistake


If this type of pixel is something not currently supported by the latest hardware, one of those providers might be able to solve the problem. Until then, I'm ruling this out as operator error until I can see more evidence.

I'm basing an opinion on what has been presented before me. Without the company and product information... it is what it is.


I definitely have to agree with Williams' assesment here. If I got a bad item/product, first thing I'm going to do is post a link to the item in question so others can take a look at it and see, #1. is it something they've purchased and tried or #2. is this something no one has tried yet and needs further investigation. or #3. Have I misunderstood the instructions and wired something incorrectly.

To the original Poster that started this thread:

Just coming out and stating "watch out for xyz corporation" and not providing links or evidence to back up the claims, well, in most folks case, that takes on an air of suspicion as to "what is the real problem". Is it actually operator error or a misunderstanding of how the product works or is designed to work?


Just because you have an engineer working with you, and you have been in the industry for a long duration still doesn't make it crystal clear as to what the problem is with these pixel strings you're complaining about.

I've been involved in electronic prototyping engineering labs, worked with electronic and electrical engineers and they *do* make mistakes, I've caught many in my time when I was just an electro-mechanical assembler on the production floor that had to be redone and reworked because of an engineering mistake/error that didn't get caught during the initial phase of prototype tests and assembly.

I have also been an electro-mechanical tech as well, and this is a never ending learning experience due to product changes, new developments and advancements in technology.

It is literally impossible to keep up with all of these changes and advancements in the electronics world. Been there, done it, made my share of mistakes too, we're human, but to out and out bash a company without providing us any evidence here, well that wouldn't hold up very well with most of the folks I worked with, and it doesn't seem to hold up here very well either.

Supply the link for the product you claim doesn't work, this is so others can view and see for themselves if this is really a product flaw, or one that truly will not work with LOR Controllers, or was something actually missed by the end user.

No links to the evidence will, and does make one very suspicious of your claims, even if you say it isn't "relevant", which honestly HOW IS THIS NOT RELEVANT when you're the one stating the product does not work correctly? Seems pretty darn relevant to me!
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DevMike wrote:

IMHO, I didn't see anyone asking for advertising here. Just more info so they could have helped you.

FYI... If there is anything that I have learned being a software guy it's that even 2 well trained people can be wrong sometimes. You should NEVER feel insulted when people offer to help, even when you believe yourself to be a master in your field. Being in the field for nearly 30 years (first person who makes a punch-card joke is going to be smacked), a single day has not gone by where someone didn't teach me something.

The people that posted were trying to help in their own way. They can't help you get your money back, but they could have helped to salvage what you already have invested.


Punch cards Mike? LOL I remember those in my High School Days!

But you're right on with the always learning from others, and that even the experts make errors. Have my own experiences with that myself that backs up exactly what you're saying.
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plasmadrive wrote:

Is it really that difficult to post a link? The people who are responding to this thread have been using pixels for a while and know a great deal about doing it the wrong way! Pixels can be very finicky. Chances are very good that you didn't even get the right chip to begin with. Hey, what do I know, I don't have my own engineer!

I didn't post here to advertise for that company.. only to warn you about how they do business when something doesn't go quite right.  The actual product was not really that relevant to my post... so, no link..

I am an electronics engineer and I have a software engineer that works with/for me.. and I assume we have a clue what we are doing... (hopefully) Especially since architectural LED art systems are part of what we do...  So chances are we got the right chip to begin with...

I posted the info I wanted to post to warn others..  Can't really see any need to discuss it further.. like I said earlier, salute or not.. it's up to you..

What is there to warn about if we dont even know what you purchased in the first place? There were some simple questions asked to which it seems you elude to answer so how is it not know that you made the mistake and not them, and now you are just blaming them?

People here are willing to help but you are refusing to let them help see what the problem is!
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You all seem to get the product and the company issues mixed together. The product, as I stated in the first place does not operate correctly on the standard 6803 controllers. I went thru butt loads of tests and so on.. all of which I am not willing to go thru here.... you will just have to trust that I know how to hook up the four wires and run the controllers since I have lots of OTHER brands of pixels running just fine. These pixels actually address and dim as well, they just flicker except at 100% brightness, and it appears to be for the reason I stated in the first place.

I did not ask anyone for help on fixing the flicker because at this point I just don't care anymore. I have spent way to much time with them and by ourselves dealing with these issues. Their solution was "we don't know therefore go somewhere else". So all the tech data is not relevant to my intention to warn others of the company.... Of course if you believe I don't have a clue as to what I am doing.. which may very well be your opinion.. so be it..

I have warned you about the company via my experience.. take it or leave it.. again, if you don't believe me, so be it.. Doesn't bother me either way.. I have done my bit in an attempt to contribute, (won't make that mistake again).. I have moved on from them. You'll don't have to, you can look them up and spend as much money with them as you can afford... or not.. again.. it is up to you.. no one is twisting your arm..

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plasmadrive wrote:

You all seem to get the product and the company issues mixed together. The product, as I stated in the first place does not operate correctly on the standard 6803 controllers. I went thru butt loads of tests and so on.. all of which I am not willing to go thru here.... you will just have to trust that I know how to hook up the four wires and run the controllers since I have lots of OTHER brands of pixels running just fine. These pixels actually address and dim as well, they just flicker except at 100% brightness, and it appears to be for the reason I stated in the first place.

I did not ask anyone for help on fixing the flicker because at this point I just don't care anymore. I have spent way to much time with them and by ourselves dealing with these issues. Their solution was "we don't know therefore go somewhere else". So all the tech data is not relevant to my intention to warn others of the company.... Of course if you believe I don't have a clue as to what I am doing.. which may very well be your opinion.. so be it..

I have warned you about the company via my experience.. take it or leave it.. again, if you don't believe me, so be it.. Doesn't bother me either way.. I have done my bit in an attempt to contribute, (won't make that mistake again).. I have moved on from them. You'll don't have to, you can look them up and spend as much money with them as you can afford... or not.. again.. it is up to you.. no one is twisting your arm..

So how am I suppose to know what product not to buy if you don't tell us what it was??? Just asking.
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