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 BulbDial Works but some red LED's switch on
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By: Anonymous: MisterD () on Thursday, December 31 2009 @ 05:16 AM PST (Read 4153 times)  
Anonymous: MisterD

Hiya.
Thanks for reading.

Just wondering if anyone else has this or if its a "problem" at all.

The main 3 LED's work I.e HMS but I've noticed that in addition to the hour LED lighting, there are other red LED's that switch on but not as bright..
Almost as if it's adding ambient lighting to the clock face.

Is this right or is this a known issue?

Thanks
MisterD





       
   
By: Windell (offline) on Thursday, December 31 2009 @ 09:27 AM PST  
Windell

There may be some faint ghosting, but it should only be apparent if you're looking, carefully, at the LEDs themselves-- it should definitely NOT be visible to a casual observer. If it's more than that-- like the LEDs are really "on" --then there are still remaining issues.

You should go back to alignment mode to look at the situation more carefully and evaluate when the extra LEDs come on-- is it only when the red ring is on, or is it the case for blue and green as well? Are there any LED sequencing issues, or is this just always the case?

In any case, you might want to touch up R10 and the various connections to the wire jumpers on the main board and top ring-- a flaky connection there can definitely cause this sort of thing.


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By: Anonymous: riese () on Tuesday, January 05 2010 @ 12:21 PM PST  
Anonymous: riese

Quote by: Windell

There may be some faint ghosting, but it should only be apparent if you're looking, carefully, at the LEDs themselves-- it should definitely NOT be visible to a casual observer. If it's more than that-- like the LEDs are really "on" --then there are still remaining issues.

You should go back to alignment mode to look at the situation more carefully and evaluate when the extra LEDs come on-- is it only when the red ring is on, or is it the case for blue and green as well? Are there any LED sequencing issues, or is this just always the case?

In any case, you might want to touch up R10 and the various connections to the wire jumpers on the main board and top ring-- a flaky connection there can definitely cause this sort of thing.



I'm having the same probs here. blue and green worked fine - after installing the red one two reds are lighting with each blue one. e.a. blue D14 on -> reds at positions one and eight are on, blue D24 on -> reds ad 2 and 8 are on, D34 on -> 6 and 8 are on,
D54 -> reds 8 + 10
D64 -> reds 5 + 8
D15 -> r eds 1 + 11
D25 -> reds 2 + 11
D35 -> reds 6 + 11
....
Any ideas?

the red ring itself works fine. in the calibration mode just one red is lighting at one time. in calibration mode for blue ring the effect is each time the same (described above)...





       
   
By: Windell (offline) on Tuesday, January 05 2010 @ 01:14 PM PST  
Windell

>I'm having the same probs here.

Are the red LEDs turning on at high brightness, or is this only at the very dim level-- as discussed -- that you can primarily see by looking at the LEDs themselves?


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By: Anonymous: riese () on Wednesday, January 06 2010 @ 01:02 AM PST  
Anonymous: riese

Quote by: Windell

>I'm having the same probs here.

Are the red LEDs turning on at high brightness, or is this only at the very dim level-- as discussed -- that you can primarily see by looking at the LEDs themselves?



they are not as bright as the hour red led - but there is a shadow visible -> you see 1 "dark" hour shadow and 2 "lightgray" shadows...





       
   
By: Windell (offline) on Wednesday, January 06 2010 @ 02:49 AM PST  
Windell

On mine, the red LEDs do come on *just a little bit* while in blue alignment mode. It's the faintest ghosting. I can tell this by holding a business card *right in front* of the LED and looking at it there light-- I cannot see any projected spot at all in a moderately lit room, and certainly not in a bright room or when all three LED rings are lit. Actually, I can't see any shadow at all from the red even when I block the blue LEDs in a not-very-well lit room. It should be possible to get yours to the same level. Not 100% off, but pretty darned close-- a casual observer should *never* see extra red shadows.

Zeroth observation: Everything that I'm going to discuss in the following supposes that every single red LED lights correctly in sequence. (If the red LEDs light out of sequence, or one is off but only lit when its neighbor is, you probably have a backwards LED.)

First observation: There are a number of places that poor solder joints can cause multiple red LEDs to come on at a time. This isn't my first guess... assuming that all of your red LEDs come on (roughly) equally bright, it's not likely that you have a symmetric arrangement of errors. Wink

First question: What value resistor do you have at location R10? The wrong value could cause this.

Second question: Is your red unusually bright? If (for whatever reason) your red is much brighter than it should be, you might see something like this. You may wish to play with the color balance mode. If the RGB levels are correct, you should see good looking cyan, magenta, and yellow in the shadow regions.


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By: Anonymous: riese () on Wednesday, January 06 2010 @ 04:12 AM PST  
Anonymous: riese

Zeroth observation: Everything that I'm going to discuss in the following supposes that every single red LED lights correctly in sequence. (If the red LEDs light out of sequence, or one is off but only lit when its neighbor is, you probably have a backwards LED.)

First observation: There are a number of places that poor solder joints can cause multiple red LEDs to come on at a time. This isn't my first guess... assuming that all of your red LEDs come on (roughly) equally bright, it's not likely that you have a symmetric arrangement of errors. Wink

First question: What value resistor do you have at location R10? The wrong value could cause this.

Second question: Is your red unusually bright? If (for whatever reason) your red is much brighter than it should be, you might see something like this. You may wish to play with the color balance mode. If the RGB levels are correct, you should see good looking cyan, magenta, and yellow in the shadow regions.
[/p]



Ok... In the alignment mode everything works fine on the green and the red ring -> all LEDs are comming up in the right sequence, no two leds at once, no LED staying dark. In this mode every red LED is equally bright - even in clock mode the hour LED is as bright as the blue and greens are. -> color mixing is perfect CMY.

Resistor R10 is 68 Ohm. When it is desoldered Red Hour is disabled, but the effect that two reds are on with every blue stays. There are seconds on which the reds are very dim level (21) and some (9) where they are brighter - but not as bright as the "right" hour LED but with a noteable shadow.





       
   
By: Windell (offline) on Wednesday, January 06 2010 @ 04:43 AM PST  
Windell

> There are seconds on which the reds are very dim level (21) and some (9) where they are brighter

Can you tell me which values lead to a brighter case?

When R10 is removed, there should be *zero* light coming out of the red LEDs-- they are not connected to the matrix. Perhaps you have a partial connection somewhere to R10... Perhaps some puddles of nonmetallic solder residue?


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By: Anonymous: riese () on Wednesday, January 06 2010 @ 05:22 AM PST  
Anonymous: riese

Quote by: Windell

>

When R10 is removed, there should be *zero* light coming out of the red LEDs-- they are not connected to the matrix. Perhaps you have a partial connection somewhere to R10... Perhaps some puddles of nonmetallic solder residue?



Lets take a little quiz... what's the difference between 5V printed on a switching power supply and the measured voltage on the output? right - 2V -> 5 + 2 = 7 ... :-(
Thanks to AVR's wide voltage range it worked without burning the mcu, but 7V is enough that the two reds are on with the blue one... grabbed another power supply with exact 5V and now it works perfect...

thanks for your help!





       
   
By: Windell (offline) on Wednesday, January 06 2010 @ 05:34 AM PST  
Windell

Every example that I've seen so far gives about 5.3 V under standard load. Did you really see 7 V under load? (!)

If this really is the cause-- that the power supply is too high under load, you could compensate by (1) adding a resistor instead of a jumper at JP1 or (2) using a larger value for R10.

In any case, if you look at the circuit diagram, every single LED on the hour ring is connected on one end or the other to R10-- if you disconnect R10 and the LEDs are still lighting up, then there really is something else wrong on the board as well; that is potentially cause for concern.

EDIT: Turns out this was not a standard power supply. Also, I was in error in the second part above-- applying 7 V to the matrix can indeed turn on the red LEDs if R10 is disconnected.


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