Your Digital Media Has Never Looked So Good

 
barrygordon
Topic Author
Posts: 275
Joined: Thu Aug 19, 2004 6:33 am
Location: Merritt Island FL
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Dead Photobridge (MB not PSU)

Tue Jan 02, 2007 1:39 pm

Well the older one of my two HD1000 Photobridge's has just died. It was repaired by Roku several years ago. This time it is not the Power supply, at least I do not believe so. All the power supply voltages read fine when connected (under load).

The visual conditions were originally that yhe "Power Light Bar" was on as was the "Busy LED", as soon as the unit was plugged in. Pushing the power button did nothing. Today it is slightly different in that the "Power Light Bar" is never on, the "Busy LED" is always on and pushing the power button still does nothing.

I suspect there is a MB issue.

It Is sad that a really elegant looking piece of gear that worked very well for what it did (especially when added to by the third party developers) has to suffer from a very very bad engineering implementation and a general lack of "We stand behind what we sell.." by Roku management.

Since I believe it is a MB problem, although I welcome any comments or ideas to the contrary, I am looking for a "dead Roku" that has died because of a PSU problem. In that way perhaps I can make one good one out of two dead ones at some reasonable cost. really all I wnt is the MB

I can not even find a number to call Roku at for RMA repair!
 
zephyr
Posts: 23
Joined: Sat Jan 14, 2006 12:53 pm

Tue Jan 02, 2007 6:53 pm

My questions:

1. How do we conclusively discover whether the issue with a non-operative Photobridge is a power supply or the mainboard? I want to avoid purchasing a HD1000 from someone claiming it is a power supply issue only to realize that installing a new power supply did no good.

2. If I bought a working replacement of the Photobridge, and then did the power supply replacement to one external to the Roku cabinet --- thus eliminating the heat issues --- would it still be a matter of (short) time until I have mainboard issues? Or would such a thing have a reasonable expectation of more than one or two years of service?
 
barrygordon
Topic Author
Posts: 275
Joined: Thu Aug 19, 2004 6:33 am
Location: Merritt Island FL
Contact:

Tue Jan 02, 2007 7:09 pm

Good questions.

If the proper power supply voltages are at the motherboard connector, then the Power supply is probably Okay. If one of the voltages is missing, is low (by 10% or more) or has a bad ripple factor (you would need an oscilliscope to see that) then it is AT LEAST a bad power supply.

The Photobridge mothernoards fail a lot, but probably not as much as the power supply. I have had two fail (Mother boards).

Good questions and I can not answer the second one.
 
dashman
Posts: 3
Joined: Fri Jan 19, 2007 10:03 pm

REPAIRING a Dead HD1000 when the Power Supply test OK !!!???

Wed Jan 24, 2007 6:53 pm

After doing some research on this...I discovered something....
You could replace the capacitors with QUALITY hi-Temp ones....Or....
When your power supply has not cooked the capacitors up to nothing,
The next big failure is.....Core Voltage Regulator......

There are THREE regulators on the motherboard.
If any one fails, you have a RokuBrick.
THe supplys are +1.8v (CPU) +2.5v (RAM) and +1.5v CPU.
They all have test-points...
(Thanks Roku (not) for absolutely no information on this email request.......Sarc)

The 1.8v & 2.5v supplys run cool.
On mine, the +1.5v went out...showed signs of heat.
I replaced the regulator ($3.00) and the Roku is ALIVE again.
All fine...except the Regulator runs at a Cool 80 Degrees C. !!!!!
Well within the 125 degree datasheet, but that is at Room Temperature.
Put that in a case with a Hot power supply 1/2" away and I think we
know why the HD1000 are failing !!!!!

The heat-sinking area on the motherboard is undersized (Very Small)
I will be conducting current measurements from the power supply to find
an appropriate supply. There are very good 'Medical Grade' externals
that I will be using with a 5 pin DIN.

I hope you all dont 'trash' your bricked HD1000's because of a $3 part....
Why do so many companies miss the basic things ??
Heat Kills...I Test things for a living...For Shame Roku.......

By the way, this IS A VERY DELICATE REPAIR....THESE PARTS ARE SMALL
MOST will be unable to do this...really....they are REALLY small, not to mentioned the ROHAS Solder which does not melt (Hate that stuff!!!)

Funny, all my old VCR's are still running...Most of the newer ones have Died (supplies)

By the way, even when the HD1000 is OFF, the regulator is still at 80 DegCelc. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! (ROKU---SLeep Mode ?????)
Even our company went to China....Ughhhh

Hey Roku, LOVE your products...really...Just build them to last=Customer for life !!

Eric

"More Roku Products in the house than TV's"
DesignNut
 
barrygordon
Topic Author
Posts: 275
Joined: Thu Aug 19, 2004 6:33 am
Location: Merritt Island FL
Contact:

Wed Jan 24, 2007 7:12 pm

The regulater is a national semiconductor part LP3965EMP-ADJ. All three regulaters are the same. The ADJ means adjustable based on external componets. The EMP designation is to get the right physical configuration, SO223-5 case if I remember correctly. They are $2.88 apiece from Digikey. The problem is in the removing of the bad SMT components and replacing them. Genrally need some special equipment or someone with experience in the field. I am going to look for the later in my area.
 
Burkhardi
Posts: 1943
Joined: Tue Jun 07, 2005 11:06 am
Location: Austin, Texas ...Y'all

Shuold all three regulators (on the MoBo) be on at sleep?

Thu Jan 25, 2007 1:46 pm

Should all three have voltage output even in standby, or just when it's on (green light). When my unit (spare one) it in standby/sleep (well, that's all I have since it will not power on I guess) I only have output voltage on two of the three. I found this out about 3 motnhs ago, but never looked further due to the holidays and such. After seeing this post, I have a new flame under my butt :P
Thanks, Matt

PS, yes, I think I remember that all three are the same part, just different values of compnents in the circuit to set the output voltage.

barrygordon wrote:
The regulater is a national semiconductor part LP3965EMP-ADJ. All three regulaters are the same. The ADJ means adjustable based on external componets. The EMP designation is to get the right physical configuration, SO223-5 case if I remember correctly. They are $2.88 apiece from Digikey. The problem is in the removing of the bad SMT components and replacing them. Genrally need some special equipment or someone with experience in the field. I am going to look for the later in my area.
Roku3 and Roku HD1000 [Rev B] on a Samsung HLP5674W DLP in the living room; a Roku2 and two Roku XS and a few SoundBridges.Win7; Kubuntu and XP via RT-N66U, E2000 and a switch or two. I own stock in Roku, it's just all in the form of hardware.Viva la Roku
 
dashman
Posts: 3
Joined: Fri Jan 19, 2007 10:03 pm

HD1000 Internal Power Supplies

Thu Jan 25, 2007 4:48 pm

The 3 voltages are there allways....It never sleeps.....Its allways HOT
Allways drawing mega current for the CPU core....

I first added a 4 sq inch copper heatsink and dropped the temp by 30 degrees !

I will be adding a flat fan, because although the copper heatsink works,
when you button it up, the temp fires up...too much for me....

Put a small value resistor inline with the fan and it will run slower & quieter...
3 watt, or higher, depending on fan....

BE CAREFULL...if you even THINK of doing this........Inspect with
magnifying lenses...or else......Mods like this stink...Hopefully ROKU
will impliment this in their NEXT version.......IT IS NEEDED !!!!!!!!!!!!!!!!

Eric
DesignNut
 
Burkhardi
Posts: 1943
Joined: Tue Jun 07, 2005 11:06 am
Location: Austin, Texas ...Y'all

Re: HD1000 Internal Power Supplies

Thu Jan 25, 2007 6:56 pm

Well one of mine has no output so Digikey, here I come!
Thanks, Matt

dashman wrote:
The 3 voltages are there allways....It never sleeps.....Its allways HOT
Allways drawing mega current for the CPU core....

I first added a 4 sq inch copper heatsink and dropped the temp by 30 degrees !

I will be adding a flat fan, because although the copper heatsink works,
when you button it up, the temp fires up...too much for me....

Put a small value resistor inline with the fan and it will run slower & quieter...
3 watt, or higher, depending on fan....

BE CAREFULL...if you even THINK of doing this........Inspect with
magnifying lenses...or else......Mods like this stink...Hopefully ROKU
will impliment this in their NEXT version.......IT IS NEEDED !!!!!!!!!!!!!!!!

Eric
Roku3 and Roku HD1000 [Rev B] on a Samsung HLP5674W DLP in the living room; a Roku2 and two Roku XS and a few SoundBridges.Win7; Kubuntu and XP via RT-N66U, E2000 and a switch or two. I own stock in Roku, it's just all in the form of hardware.Viva la Roku
 
dashman
Posts: 3
Joined: Fri Jan 19, 2007 10:03 pm

Fix-A-Brick - Replacing a Voltage Regulator---Caution !!

Thu Jan 25, 2007 7:27 pm

Remember, Thats Lead-Free Solder I believe...It requires a Hotter Temp to melt, and its soldered to a ground plane........

Good Luck!
DesignNut
 
Burkhardi
Posts: 1943
Joined: Tue Jun 07, 2005 11:06 am
Location: Austin, Texas ...Y'all

Re: Fix-A-Brick - Replacing a Voltage Regulator---Caution !!

Fri Jan 26, 2007 7:50 am

Dashman- Well good gravy, I didn't know that. I assumed it was like the power supply solder.
I'll have to go to my friends shop and do it there. Thanks for the great info!!
Thanks, Matt

dashman wrote:
Remember, Thats Lead-Free Solder I believe...It requires a Hotter Temp to melt, and its soldered to a ground plane........

Good Luck!
Roku3 and Roku HD1000 [Rev B] on a Samsung HLP5674W DLP in the living room; a Roku2 and two Roku XS and a few SoundBridges.Win7; Kubuntu and XP via RT-N66U, E2000 and a switch or two. I own stock in Roku, it's just all in the form of hardware.Viva la Roku

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