Sdi ports

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FrankApollonio

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Sdi ports

PostTue Feb 27, 2018 2:55 am

Hey! So my sdi main went a few months ago and ive been awkwardly skipping waiing for (hopeful nab canera) and now my freaking front sdi is going... this is what im talking about... charge me an extra grand and have everything be a tank... i dont want to send my camera in... i honestly cant bc i have shoots every week... why would you make ******** sdi ports!?!?!? They are so sensitive.
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Xtreemtec

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Re: Sdi ports

PostTue Feb 27, 2018 10:59 am

I really wonder what you have hanging on those SDI ports and how you power that.. SDI ports don't just break..

Also not using propper BNC connectors can physically damage your SDI connectors to the point that they are bend to much to the outside they don't make conact anymore.

So without a propper background on how you are using it, there is no way telling you why they have failed.. ;)

As you are talking about front and backport i assume that we are talking Ursa? (Ursa mini?? )
What cables / connectors do you use?
Daniel Wittenaar .:: Xtreemtec Media Productions ::. -= www.xtreemtec.nl =-
4K OBV, ATEM TVS HD, 1M/E 4K, 2M/E Broadcast Studio 4K, Hyperdeck Studio Mini, SONY FS7 4K, Ursa Broadcast 4K
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Anatoly Mashanov

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Re: Sdi ports

PostTue Feb 27, 2018 12:47 pm

1. Be sure that you power your camera and your monitor from separate batteries. Never economize on batteries.
2. As I understand, SDI is scrambled. So a small capacitor in serial and some TVI suppressor, for instance, Philips PESD in parallel, would suffice for protection of SDI. I wonder why it was not done before.
3. I have repaired lots of stuff killed with static. In half of cases there were Philips PESD which were burned and shorted the link. Maybe it's already a burned protector that shorts your output?
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Xtreemtec

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Re: Sdi ports

PostTue Feb 27, 2018 2:09 pm

Anatoly Mashanov wrote:1. Be sure that you power your camera and your monitor from separate batteries. Never economize on batteries.

This even creates power issues.. ;) There will be potencial voltage differences between power sources.

Anatoly Mashanov wrote:2. As I understand, SDI is scrambled. So a small capacitor in serial and some TVI suppressor, for instance, Philips PESD in parallel, would suffice for protection of SDI. I wonder why it was not done before.

Every SDI input and output has a small capacitor directly behind the connector. A PESD will influence the SDI signal in the wrong way. Impendance of SDI comes very critical.
Anatoly Mashanov wrote:3. I have repaired lots of stuff killed with static. In half of cases there were Philips PESD which were burned and shorted the link. Maybe it's already a burned protector that shorts your output?

There is no PESD in there.. Small capacitor and some resistors to do 75 Ohm coupling. After that it goes directly into the driver or receiver for monitors and mixers..

SDI is +/- 400mv signal. So max 800/900mv peak..

If you have a power potential difference that is greater then 10V or so the capacitor will not protect you anymore.. Grounding people, grounding is everything!!
Daniel Wittenaar .:: Xtreemtec Media Productions ::. -= www.xtreemtec.nl =-
4K OBV, ATEM TVS HD, 1M/E 4K, 2M/E Broadcast Studio 4K, Hyperdeck Studio Mini, SONY FS7 4K, Ursa Broadcast 4K
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FrankApollonio

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Re: Sdi ports

PostTue Feb 27, 2018 4:05 pm

ursa min, using smallhd 2ft sdi cables... the thin ones for movi pro work. I don't abuse my gear at all... I have been powering my 702 from the camera battery. but that shouldn't kill a port... or why would they give you the option.
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Denny Smith

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Re: Sdi ports

PostTue Feb 27, 2018 7:19 pm

How are you,powering it from th camera battery, the 4-pin xlr on the camera front, or the DTap from the rear or straight from the battery DTap? The first two are somewhat island should be fine, directly from the battery could cause issues.
Cheers
Denny Smith
SHA Productions
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FrankApollonio

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Re: Sdi ports

PostTue Feb 27, 2018 8:29 pm

i tend to power smallhd702 from battery plate.
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Anatoly Mashanov

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Re: Sdi ports

PostWed Feb 28, 2018 2:05 am

Xtreemtec wrote:Every SDI input and output has a small capacitor directly behind the connector. A PESD will influence the SDI signal in the wrong way. Impendance of SDI comes very critical.

Philips PESD series is a specialized series of semiconductor devices designed specifically for this purpose (such as HDMI and Ethernet, gigabit included), with capacity about 1 pF. And they are dinistors, not avalanche diodes as traditional TVS and transzorbers.

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