Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
Hi to everybody, Yesterday 1-2 minutes after powerup i heard a loud pop from the speakers and the Buffalo II stopped working. AVCC module and Tridents leds are lit, but except the 3.3V VDD_XO trident, other voltages seem not correct. The lock led stays always lit but dimmed regardless of digital input presence. The Placid powering the Buffalo Board seems to be working fine. Can you please help continue troubleshooting? Edited by user Saturday, May 28, 2011 3:46:14 AM(UTC)
| Reason: Not specified
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 6/17/2008(UTC) Posts: 921  Thanks: 1 times
Was thanked: 70 time(s) in 69 post(s)
|
It seems that you have a Trident that has given up.
Try removing it and reinsert the ferrite bead. Is you BII working now ?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
I removed the 1.2V trident and reinseted the L6 ferrite bead. That caused the voltage to drop at Placid output, like having some kind of short circuit, measuring 1.75V.
Removing L6 reverts Placid output to a normal 5.5V.
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
This is an indication that there could be a short or possibly a damaged DAC chip,
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
I cannot think how a short could happen, it's more probable that something damaged the DAC chip.
Is there any way to repair?
|
|
|
|
|
|
Rank: Advanced Member
Groups: Member
Joined: 3/31/2011(UTC)
Posts: 45
Location: Malaysia
|
First post you mention 3.3v VDD_XO trident not lite up, the next you do is removed the 1.2v trident! Why?
Why don't you removed all 3 tridents? Do you smell something burn when it happen?
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
Maybe i didn't explain this clearly.
With all Tridents installed, all regulator leds are lit (Tridents and AVCC) but the only voltage that seems correct is the one from the 3.3V VDD_XO Trident.
I removed the 1.2V Tridend as i was measuring a few mV there and inseted the L6 ferrite bead. That worked as a kind of short to the Placid as i was measuring about 1.75V at its output. Of course none of Buffalo's leds were lit.
I thought that if the 1.2V Trident failed for some reason, reverting to the original regulator would bring me at least this 1.2V right. Then i would continue with the other tridents. This did't happen so i guess that there is a problem on the "after regulator" side.
I will remove all regulator modules and test them isolated from the board.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
Measured voltage of isolated regulators (no output load, Vin=5.5V)
3.3V Trident1: 3.35V
3.3V Trident2: 3.31V
1.2V Trident3: 1.215V
AVCC Mod out1: 3.52V
AVCC Mod out2: 3.52V
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
Yep, sounds like the problem is after the regulator. The 1.2V pins of the DAC chip are the most sensitive to ESD. Unfortunately from here that's what sounds like happened to your DAC. The only cure for that is to replace the DAC.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
You mean replace the DAC chip or the whole DAC board?
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
You could probably replace the chip. But that is no simple task.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
I understand and i don't have the necessary tools to do it.
Could you provide such a service?
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 3,979
Location: Nashville, TN
Thanks: 25 times
Was thanked: 89 time(s) in 83 post(s)
|
Unfortunately I cannot. It it is likely not cost effective in any case.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 11/3/2010(UTC) Posts: 169  Location: Quebec
|
I have a customer that can easily do this task. They're in the satellite business
You would still have to buy a spare ES9018 which is around 60$ plus shipping both ways and if you're lucky I can get this job done for free.
You also have to make sure nothing else is damaged otherwise it is of no use...
Best option would be to buy a new unit when they're available again.
Russ, Brian,
Could you PM me if you have a used Placid BP model in stock, generation just before the Placid HD? I have 3 of this generation and would require another one to complete my setup.
Thanks
Do
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
There is a possibility that something else is also damaged, but i don't know how to check this.
I could buy a new DAC board, but i see there's not any pre-order date in the near future.
Pinnoccio,
Thank you for be willing in helping me, i will take my chances and try changing the DAC chip.
I will PM you for details.
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 11/3/2010(UTC) Posts: 169 Location: Quebec
|
If we can have it repaired by my customer, once I get it back I'll be able to test it since I have spare IVY III and power supply.
I will keep you updated
Thanks
Do
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
This is great! Thank you for your help. Edited by user Thursday, June 2, 2011 5:56:07 AM(UTC)
| Reason: Not specified
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 11/3/2010(UTC) Posts: 169 Location: Quebec
|
Hey ManosP,
Great news for you my friend! My customer will do it as a favor, so no charges!
Just keep in mind that if other parts are defective, like the opamps/regulators then it still won't work after the chip change. You're taking a chance.
I will PM you the shipping information.
Ciao!
|
|
|
|
|
|
Rank: Member
Groups: Member
Joined: 5/28/2011(UTC)
Posts: 17
Location: Athens
|
Great news indeed!
I understand the risk but i'll take my chances.
I feel lucky.
Best Regards.
|
|
|
|
|
|
Rank: Administration
Groups: Administration, Customer
Joined: 10/24/2006(UTC)
Posts: 2,868
Location: Massachusetts, USA
Thanks: 2 times
Was thanked: 141 time(s) in 134 post(s)
|
Testing the onboard regulators should be easy. Just remove the ferrites (the ones you remove for trident installations), power the DAC and measure the voltages at the ferrite locations.
There are no opamps on the board, so no troubles there.
|
|
|
|
|
|
Forum Jump
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.
