MY SDI input on my BMCC Stop Working

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Toroes Thomas

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MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 9:21 am

Hi I just brought a IKan D5 monitor for my BMCC. After I updated my camera to the new software and used my monitor 2 times on a music video shoot my SDI input on my my monitor and camera stop working. When I tried my monitor on a friends Bmcc it didn't work and when I tried his monitor on my cam it didn't work. I called Black magic and they want me to send it in but I am just wondering has this happened to anybody else?
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Mubarak Almubarak

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 10:26 am

Were you using an external battery?
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Alex Molas

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 7:51 pm

Pretty common issue, has happened to me and to several others...
I'm sorry to inform you that, not only your SDI interface burned itself as it also fried your monitor!

I feel your pain.
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Toroes Thomas

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 8:11 pm

Mubarak Almubarak wrote:Were you using an external battery?



Yes I was using my my external battery.
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Toroes Thomas

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 8:12 pm

Molas wrote:Pretty common issue, has happened to me and to several others...
I'm sorry to inform you that, not only your SDI interface burned itself as it also fried your monitor!

I feel your pain.


What did you do about it? and if you fixed it how much did it cost?
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Joe Kreidel

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 9:50 pm

Happened to myself as well. I sent it in to Blackmagic, and they quickly fixed it, and returned it to me at no charge.

The SDI input on my monitor also fried, and I am waiting for it to be returned from Birns and Sawyer (US Cineroid reps), who were very responsive and easy to deal with.

Since this is a common problem, does anyone know if there is a way to use an external battery and avoid the problem, or are we always likely to have this happen again?
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Alex Molas

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 03, 2014 11:50 pm

Toroes26 wrote:
Molas wrote:Pretty common issue, has happened to me and to several others...
I'm sorry to inform you that, not only your SDI interface burned itself as it also fried your monitor!

I feel your pain.


What did you do about it? and if you fixed it how much did it cost?


My BMCC was still under the warranty period so I sent it to Blackmagic and they repaired the camera for free. I had to wait about a month and a half but the camera came back in fully working condition.

Unfortunately I gave up on the monitor since the repair was way too expensive.

The thing is, I'm always thinking when this will happen again now that my BMCC is out of the warranty...It's like shooting with a time bomb :P !
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Robert Niessner

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Re: MY SDI input on my BMCC Stop Working

PostMon Aug 04, 2014 4:23 am

This has been discussed on this forum and it seems the common factor for all cases was the usage of the Tilta battery plate.
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Joel Crane

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Re: MY SDI input on my BMCC Stop Working

PostMon Aug 04, 2014 9:12 am

Robert Niessner wrote:This has been discussed on this forum and it seems the common factor for all cases was the usage of the Tilta battery plate.


It happened to me without the usage of a battery plate.
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João Gomes

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Re: MY SDI input on my BMCC Stop Working

PostMon Aug 04, 2014 2:22 pm

Same happened to me.

Fried both the camera and the Cineroid monitor. Had to wait for three months to get my camera back. I had just bought the monitor from B&H and they were super quick to send me another one.
I was using a Tilta baseplate.
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Joaquin Torrents

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Re: MY SDI input on my BMCC Stop Working

PostMon Aug 04, 2014 9:40 pm

Same here, using an Alphatron and Titla plate. Camera was under warranty and took two weeks to be repaired. Since then, I'm using a Hawk Woods plate...
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Lee Gauthier

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Re: MY SDI input on my BMCC Stop Working

PostMon Aug 04, 2014 11:26 pm

What's the best practice for avoiding frying both the port and the viewfinder? Has someone found a workaround?

Thanks
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Serena Steuart

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 10, 2014 4:42 am

I'm looking at battery power supply systems where I want 12v and 5v outputs and the Tilta battery plate looks very attractive. However having the SDI connections blown is to be avoided but it seems that no-one has identified the actual problem. Is it a problem with common ground polarity when the Tilta is rail mounted? Is see one other post with the same problem with a different plate. Any understanding of the problem? Any recommendations for plates that don't blow the SDI on cameras and monitors?
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Mubarak Almubarak

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 10, 2014 9:24 am

Serena Steuart wrote:I'm looking at battery power supply systems where I want 12v and 5v outputs and the Tilta battery plate looks very attractive. However having the SDI connections blown is to be avoided but it seems that no-one has identified the actual problem. Is it a problem with common ground polarity when the Tilta is rail mounted? Is see one other post with the same problem with a different plate. Any understanding of the problem? Any recommendations for plates that don't blow the SDI on cameras and monitors?


No one knows for sure what is causing this problem. There were some people who were using different plates and had the same problem, other people didnt even use an external battery and also had the same problem.

there were many discussions in this forum and BMCC user, and no one can identify for sure what is causing this issue
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Alex Molas

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Re: MY SDI input on my BMCC Stop Working

PostSun Aug 10, 2014 11:04 am

Yeah there isn't a pattern, this has happened to different setups with different gear, with and without converters and even without the use of an external power supply.

I guess the problem it's the camera's SDI port itself which seems to be kinda fragile.

On the other hand, some people just uses it with all sort of devices and cheap chinese converters and never had a single problem, so luck (as in everything else) also plays a part of it.
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Juan Rojas Mancha

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Re: MY SDI input on my BMCC Stop Working

PostWed Aug 13, 2014 11:47 pm

hello someone knows if this only happens with BMCC and not with BMPC 4k?
and if within the BMCC happens to the first units or all
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Chris Kurose

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Re: MY SDI input on my BMCC Stop Working

PostThu Jan 08, 2015 5:40 pm

It has happened to us twice with the BMPC 4K. It's currently out for repair for the second time now, thankfully still under warranty, but just barely. This time around in my conversations with Blackmagic product support I was told that the problem could be caused by my external battery: "There is a ground loop potential on some external systems which incorrectly puts voltage on the SDI connector. This should not be done but it happens on some setups and can damage the SDI connector." The camera is just passing out of warranty now so it's a moot point, but they told me they would not continue to repair the same issue for free after this time.

We've been using Switronix Powerbase 70's (with no battery plate, just Switronix's adapter thing to the camera and an Ikan D-tap cable to the monitor) to simultaneously power the camera and our Ikan D5 monitor, but we won't be doing that going forward, although it will be inconvenient to use two external batteries instead of one.

If anyone knows of a cost-effective solution that would allow us to keep powering multiple accessories with the same battery that would be awesome!
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rick.lang

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Re: MY SDI input on my BMCC Stop Working

PostThu Jan 08, 2015 10:42 pm

Chris, there's one or more long threads on the BMC user forum related to ground loop problems. Having separate batteries for each device is one way to avoid the ground loop problem. Perhaps having the battery connected to a battery power plate that has independent circuits for its outputs is another solution. I believe the problem was more prevalent on certain lower cost battery plates so in this case it's worth paying a little more for better quality.


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Chris Hocking

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Re: MY SDI input on my BMCC Stop Working

PostFri Jan 09, 2015 3:54 am

We blew the SDI output on our BMCC a few months back, and it was fixed under warranty. Our SmallHD monitor was fine. We're using a Wondlan V-Mount Adapter plate that powers our BMCC & SmallHD.

I think as others have suggested, the camera is just a bit fragile, as it seems to be a very common issue regardless of what monitors or external batteries you're using.
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David Green

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Re: MY SDI input on my BMCC Stop Working

PostFri Jan 09, 2015 5:53 pm

The SDI Interface is static sensitive.
Why more manufacturers do not put warnings on their SDI-equipped gear is beyond me.
Never connect or disconnect the cable while either unit is powered on.
If each device has its own power (eg. individual batteries), it would be best if there was an additional grounding cable (even temporary) between the two devices while the cable is being connected or removed.
Observe all static handling precautions when cabling any SDI device, which includes making sure that you are not carrying any static charge, discharge yourself first or use a wrist grounding strap.
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Cam Macduff

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 8:30 am

Wow, surprised this hasn't been solved yet. This problem just seems to go on and on.
Meanwhile I keep using my relatively cheap Lanparte plate and batteries to power my BMCC and Atomos Blade without issue. Very random.
Has there ever been a statement from BMD themselves on the issue?
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Mubarak Almubarak

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 9:28 am

Cam Macduff wrote:Has there ever been a statement from BMD themselves on the issue?


well, kind of.
It wasnt an official statement, it was just mentioned on the forums a while back. at the time they thought it was caused by a monitor

viewtopic.php?f=2&t=13487&p=85571&hilit=lilliput+lilliput+sdi#p85571

Eddie Wee wrote:Please be careful when connecting Lilliput 7" monitor to BMCC directly or indirectly. You may lose the SDI output of BMCC. There are few reported cases in Asia. Please update your experience after using it.


Eddie Wee wrote:The damage is caused to the SDI output of BMCC. Have to replace the main PCB board.
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Jason R. Johnston

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 3:49 pm

I have the SmallHD AC-7, the BMCC 2.4K EF and power comes from Switronix PB-70 batteries. I connect the cables to the camera and monitor first, then to the battery. I then turn the camera on first, let it give me a picture, then turn on the monitor. When shutting down, I do the exact reverse of this. I've never had a problem.
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Chris Hocking

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 8:55 pm

We have a similar setup to you Jason (BMCC + AC7) - but with a different brand of batteries. We follow the same procedure in terms of connecting and powering up/down. Our setup worked perfectly fine for months and months of continuous work - then one day, for no reason, there was no picture to the AC7, and we discovered that the BMCC had blown it's SDI port. The engineers who fixed it said it was an EXTREMELY common problem with the original BMCC. We're not exactly sure how it happened - but can only assume it was static. After we got the SDI port fixed, it's been working fine since September with the exact same setup.
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Cam Macduff

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 8:57 pm

Chris Hocking wrote:The engineers who fixed it said it was an EXTREMELY common problem with the original BMCC.


BMD Engineers?
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Chris Hocking

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 9:02 pm

Cam Macduff wrote:BMD Engineers?


Not directly - speaking with the company that we dropped the camera off to for repair - a Blackmagic importer/wholesaler that handles all the RA's in our region.
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Cam Macduff

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Re: MY SDI input on my BMCC Stop Working

PostMon Jan 12, 2015 9:05 pm

Chris Hocking wrote:Not directly - speaking with the company that we dropped the camera off to for repair - a Blackmagic importer/wholesaler that handles all the RA's in our region.


Still, that's telling if they handle all the repairs for BM.
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John Brawley

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Re: MY SDI input on my BMCC Stop Working

PostTue Jan 13, 2015 11:20 am

I've used and own a lot of BMCC 2.5K and 4K bodies...well into double digits. Mostly factory cameras.

I've been shooting with them nearly every single shoot day for months and months since they were launched. i have months of ON time with them.

I've never ever blown an SDI port ever. I'm not even careful about how I plug things in. I have different asstants working with them and have no special routines...

I've used them with Alphatron EVF's, and various on board monitors. My 7Q, Small, TV logic...

I've got several Vlock battery plates that I use. The Wooden camera ones are what I use most but I also sometimes use the BeBob and Viewfactor.

Almost always these problems seem to happen with less "prestigious" brand items...

I think David Green here on this thread did some great detective work on an earlier thread that also seemed to indicate bad internal wiring practice in some accessories...I'm hoping he'll post to it. Is that still your view David ?

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David Green

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Re: MY SDI input on my BMCC Stop Working

PostTue Jan 13, 2015 7:11 pm

John Brawley wrote:I think David Green here on this thread did some great detective work on an earlier thread that also seemed to indicate bad internal wiring practice in some accessories...I'm hoping he'll post to it. Is that still your view David ?


Thanks John.

I posted on a thread here last year regarding this issue.
I spent an afternoon looking into this along with the SDI buffer IC design (one of my hats is an electronics engineer).


The V-Mount plate shown in the thread uses isolated grounds, which may cause ground connection contact bounce when connecting the SDI cable if the camera and EVF are using the two independent power sources on the plate.
This is why I mentioned in my post above about making sure that both devices are powered off before fiddling with the cabling.
The typical SDI buffer IC specification has a design that should be able to sink the contact bounce, so this is more of a preventative measure.
I would still personally train people to not fiddle with the cables while the units are powered on.


What I was surprised to find is that whoever in the industry designed the SDI interface only designed it with ±5kV or less ESD protection on the I/O buffer IC.
This is insufficient for outward-facing interfaces, they should always be ±15kV ESD protection or higher.
This means that if you are carrying even a small static charge, you can fry the SDI buffer IC if you touch near the center contact and cause a discharge. 5kV is so low that you most likely won't even feel it, but you will notice when your SDI no longer puts out any signal.

Many of the professional rack-mount multi-SDI interfaces have warning stickers on them regarding the static sensitivity of the SDI interface.

So any SDI static sensitivity is not the fault of BMD or any of the monitor manufacturers, they will be using the ICs supplied by a semiconductor manufacturer that is designed to the SDI industry specification.
Please note that I have not seen any BMD camera schematics and I am assuming that BMD and other SDI-equipped device manufacturers are not using off-chip ESD protection devices such as TI TPD4S/8S HSVI SMDs.

Assuming that this is in fact what is damaging the BMD camera SDI output for those people posting here, and since the ESD protection is imho insufficient, I would expect to see a small number (1 in 5,000) of people who are unlucky enough to be frying their camera.
This issue will appear to be highly random across camera users, since ESD discharge issues are also quite random.

Note that when I was looking into this, I found similar posts regarding dead SDI outputs on other camera manufacturer forums, such as Canon, etc. They will be using the same/similar SDI buffer ICs with the inherent under-rated ESD protection.

I always discharge myself when handling the SSD or SDI on my BMD camera.
It is usually as easy as touching any large metal object next to you such as a metal table or metal stand.


These same static prevention measures should be followed when handling the SSD drive.
SSD drives and the SATA interface also do not have high ESD protection.
SATA is not an outward-facing interface. SATA, mSATA, etc. are only around ±4kV ESD.

When you open your SSD drive package, keep the translucent antistatic protection bag that the drive came in, and always use it for transport and storage of the drive. Note that some blister packaged drives do not include the protection bag unfortunately.

Use care and try to never touch the drive contacts.

On computer motherboards, where you typically see SATA interfaces and SSD drives, only the outward-facing interfaces are high ESD protected, such as the Serial, Parallel, Ethernet, USB, eSATA, etc.
CPU, memory, SATA, etc., require static prevention measures when handling them.
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Chris Hocking

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Re: MY SDI input on my BMCC Stop Working

PostTue Jan 13, 2015 9:35 pm

Awesome. Thanks for the detailed reply David!
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Cam Macduff

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Re: MY SDI input on my BMCC Stop Working

PostTue Jan 13, 2015 9:36 pm

Wow. Great reply David. Much appreciated.
BMD owe you a beer at least I think :-)
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rick.lang

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Re: MY SDI input on my BMCC Stop Working

PostTue Jan 13, 2015 11:05 pm

Thanks again! I thought having the various devices on independent power circuits was enough, but good to be reminded to take the time to power down devices before cabling devices together regardless of the power source.


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John Brawley

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Re: MY SDI input on my BMCC Stop Working

PostWed Jan 14, 2015 10:49 am

Couple of things I've recently learned to add to David's comments....

It's easy to blow the the SDI driver circuit by static discharging on the internal centre pin WITHOUT grounding to the outer ring. The connector is designed to make this physically difficult to do, but it seems it can be done.

It also makes NO DIFFERENCE if the camera is on or off. Static, just like with RAM and with SSD's can cause damage no matter of the device is on and powered or not.

A good precaution is to connect the cable to the other device and ground / discharge yourself by touching the external part of the SDI connector on the camera for a second or two before plugging in the cable to the body.

You could also short the SDI if you have a dodgy cable that connected the centre to the outer ground part of the SDI when plugging in....

If you tried using electronic circuit protection it would mean you wouldn't get very long runs out of the SDI cable length, something they're awesome for at the moment... The SDI / SMPTE spec doesn't allow for this as you've learned David, and this is precisely why the spec doesn't have much protection... though there's no reason why someone couldn't perhaps do this...extra curricular ?.

It would greatly reduce the length of cable run possible. I think this is also to do with the 1.5G / 3G / 6G / 12 G technologies.....It's a bit like the different ADSL technologies trying to get more bandwidth out of the same cable...

JB
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David Green

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Re: MY SDI input on my BMCC Stop Working

PostWed Jan 14, 2015 6:45 pm

John Brawley wrote:If you tried using electronic circuit protection it would mean you wouldn't get very long runs out of the SDI cable length, something they're awesome for at the moment... The SDI / SMPTE spec doesn't allow for this as you've learned David, and this is precisely why the spec doesn't have much protection... though there's no reason why someone couldn't perhaps do this...extra curricular ?.


Any ElectroStatic Discharge (ESD) protection would have to be integrated right into the device or camera, between the internal buffer IC and the BNC connector.

For example, a small disc capacitor around 1pF would increase the ESD protection level for about 1/100th of a penny in bulk cost, but most likely would soften the signal waveform.

Companies like Texas Instruments produce ESD Protection ICs in surface-mount device packages specifically for high-speed video and data lines including Low Voltage Differential Systems, Serial Link, DisplayPort, HDMI, DVI, eSATA, etc.
However, whoever designed SDI apparently decided not to integrate these into the specification.
Whether this is due to signal slew rate and waveform quality factor, I am not privvy on that information.

So most likely our only method of dealing with this is educating people on how to prevent ESD damage to the devices.
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Jason R. Johnston

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Re: MY SDI input on my BMCC Stop Working

PostWed Jan 14, 2015 10:25 pm

Great info. Thanks, David! (and John)
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Sean Miller

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Re: MY SDI input on my BMCC Stop Working

PostSat May 16, 2015 8:06 am

Mubarak Almubarak wrote:
Cam Macduff wrote:Has there ever been a statement from BMD themselves on the issue?


well, kind of.
It wasnt an official statement, it was just mentioned on the forums a while back. at the time they thought it was caused by a monitor

viewtopic.php?f=2&t=13487&p=85571&hilit=lilliput+lilliput+sdi#p85571

Eddie Wee wrote:Please be careful when connecting Lilliput 7" monitor to BMCC directly or indirectly. You may lose the SDI output of BMCC. There are few reported cases in Asia. Please update your experience after using it.


Eddie Wee wrote:The damage is caused to the SDI output of BMCC. Have to replace the main PCB board.

really?? for any connection from monitor to camera, the most important point is to shut down the power, then connecting with each other. It's forbidden to connect when power on. It'll be harmful to the camera. this is not the problem of lilliput monitor, no matter what brand. It’s the problem who operate it.
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Re: MY SDI input on my BMCC Stop Working

PostWed Jun 10, 2015 7:59 am

David Green wrote:
John Brawley wrote:I think David Green here on this thread did some great detective work on an earlier thread that also seemed to indicate bad internal wiring practice in some accessories...I'm hoping he'll post to it. Is that still your view David ?


Thanks John.

I posted on a thread here last year regarding this issue.
I spent an afternoon looking into this along with the SDI buffer IC design (one of my hats is an electronics engineer).


The V-Mount plate shown in the thread uses isolated grounds, which may cause ground connection contact bounce when connecting the SDI cable if the camera and EVF are using the two independent power sources on the plate.
This is why I mentioned in my post above about making sure that both devices are powered off before fiddling with the cabling.
The typical SDI buffer IC specification has a design that should be able to sink the contact bounce, so this is more of a preventative measure.
I would still personally train people to not fiddle with the cables while the units are powered on.


What I was surprised to find is that whoever in the industry designed the SDI interface only designed it with ±5kV or less ESD protection on the I/O buffer IC.
This is insufficient for outward-facing interfaces, they should always be ±15kV ESD protection or higher.
This means that if you are carrying even a small static charge, you can fry the SDI buffer IC if you touch near the center contact and cause a discharge. 5kV is so low that you most likely won't even feel it, but you will notice when your SDI no longer puts out any signal.

Many of the professional rack-mount multi-SDI interfaces have warning stickers on them regarding the static sensitivity of the SDI interface.

So any SDI static sensitivity is not the fault of BMD or any of the monitor manufacturers, they will be using the ICs supplied by a semiconductor manufacturer that is designed to the SDI industry specification.
Please note that I have not seen any BMD camera schematics and I am assuming that BMD and other SDI-equipped device manufacturers are not using off-chip ESD protection devices such as TI TPD4S/8S HSVI SMDs.

Assuming that this is in fact what is damaging the BMD camera SDI output for those people posting here, and since the ESD protection is imho insufficient, I would expect to see a small number (1 in 5,000) of people who are unlucky enough to be frying their camera.
This issue will appear to be highly random across camera users, since ESD discharge issues are also quite random.

Note that when I was looking into this, I found similar posts regarding dead SDI outputs on other camera manufacturer forums, such as Canon, etc. They will be using the same/similar SDI buffer ICs with the inherent under-rated ESD protection.

I always discharge myself when handling the SSD or SDI on my BMD camera.
It is usually as easy as touching any large metal object next to you such as a metal table or metal stand.


These same static prevention measures should be followed when handling the SSD drive.
SSD drives and the SATA interface also do not have high ESD protection.
SATA is not an outward-facing interface. SATA, mSATA, etc. are only around ±4kV ESD.

When you open your SSD drive package, keep the translucent antistatic protection bag that the drive came in, and always use it for transport and storage of the drive. Note that some blister packaged drives do not include the protection bag unfortunately.

Use care and try to never touch the drive contacts.

On computer motherboards, where you typically see SATA interfaces and SSD drives, only the outward-facing interfaces are high ESD protected, such as the Serial, Parallel, Ethernet, USB, eSATA, etc.
CPU, memory, SATA, etc., require static prevention measures when handling them.


i admire you.You are so professional
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Re: MY SDI input on my BMCC Stop Working

PostWed Jun 10, 2015 11:30 am

Is anybody going to try a separating transformer (maybe a ferrite ring from a satellite splitter would be OK) or a Philips PESD?
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Frank Glencairn

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Re: MY SDI input on my BMCC Stop Working

PostWed Jun 10, 2015 4:17 pm

The only pattern (kinda) that I saw, was when folks connect the camera at one of the plate outlets and the monitor via d-tap. Not sure if it was the d-tap of the battery or the one on the plate. But you get some sort of ground issue - basically what David said.
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Set your zebras to 100%, ETTR and you're golden - and NO, you can't use TB as output for an external monitor, and you can't download the footy via TB ether.
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Anatoly Mashanov

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Re: MY SDI input on my BMCC Stop Working

PostThu Jun 11, 2015 2:25 am

Frank Glencairn wrote:The only pattern (kinda) that I saw, was when folks connect the camera at one of the plate outlets and the monitor via d-tap..


This pattern means only one: That due to some construction defect the battery voltage is applied to the input/output circuits, and no reasonable protector (including the one that survives 5KV static) would survive 12VDC.

But Wikipedia states that SDI uses scrambled NRZI which means that due to scrambling it may be reasonably immune to the loss of DC part of the signal. So it may be good to try some protector that prevents the DC and overvoltages from passing to the camera. For instance, a serial capacitor and a pair of parallel Philips PESD ESD protection diodes (Actually, super low capacity dinistors). Or a transformer wound on some super high frequency core taken from a satellite TV splitter (You could not find a super ferrite simply and cheaply in other places if you are not a microwave specialist)

I have no SDI equipment so I cannot test it myself.

JFYI: The SATA (Including the CFast cards used in URSA) uses a pair of symmetric serial lines decoupled with serial capacitors so it's reasonably immune to such problems.

Hope this helps.

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