Boosting SDI over long distances with BMD Micro Converters

We have a client who requires our cameras to be around 400m away from our ATEM but we are not in a position to splash out for fibre. We are wondering whether it would be possible to 'boost' our 80m SDI cables using BMD SDI to HDMI 3G Micro Converters?

In theory, this should work as we have tested:
Camera > 80m SDI > Converter > 80m SDI > Converter > 80m SDI > ATEM
This works fine.

My question would be whether anyone has tried this with longer runs and more converters (say, 5xSDI cables/Converters). Is it stable?

I'd ask around to rent a fibre solution, especially if this is a one-off project.

Your plan would work, but requires power at each converter location, will introduce a lot more delay to your signal (might not be an issue) and provides a lot more points of failure.

My experience with the Micro Converters is they had issues with any SDI cable longer than 50' and aren't really designed as boosters and I have no clue if they would even function this way using the SDI through.

No matter what, trying to run SDI at 400m is likely to be problematic.

I agree with the previous poster that your best option is to rent a fiber solution. Depending on where you live there may be people here that can help you.

Best,

David

I don't know what a "booster" is, I reckon y'all are referrring to a re-clocker. The re-clocker in theses units should be good for 100m @3G. If the signal is only travelling 50' before pooping out I'd have a look at the cable or termination, something is wrong.

Good Luck

The OP used the term "boost". The Micro Converters as far as I can tell aren't designed as amplifiers.

The micro converters seemed to work ok with cables to about 50'. The mini converters worked to about 200' with the same cable. No issues with bad cable or termination.

OP wants to go 400m. Some of the better amplifiers are only good for 100m. Fiber is the best solution and takes away many points of failure.

Best,

David

I don't know what a "booster" is, I reckon y'all are referrring to a re-clocker. The re-clocker in theses units should be good for 100m @3G. If the signal is only travelling 50' before pooping out I'd have a look at the cable or termination, something is wrong.

Good Luck

My experience with the Micro Converters is they had issues with any SDI cable longer than 50' and aren't really designed as boosters and I have no clue if they would even function this way using the SDI through.

50 feet????

Then you're using bad quality SDI. 1694a is rated for at minimum 100 meters at 1080i, and a lot of gear quotes more than 100m at 1080p with that cable.

I'm regularly running 80m-110m runs at 1080i with 1694f (flexible variant of 1694a), have only had to do 50m at 1080p or higher so far.

The Micro Converters as far as I can tell aren't designed as amplifiers.

The 3G Micro converters have re-clockers, SDI doesn't use boosters or amplifiers per-se, a distribution amplifier is a re-clocker. They are used to reshape/reclock the square wave for re-transmission rather than boost or amplify in the analog sense.

Good Luck

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http://www.clarkwire.com/cableCD7506P.htm - this is the cable I use.

Maybe a bad batch? Exact same cable with Mini Converters worked out to 250' at 1080P 59.94. Maybe bad converters?

Either way my recommendation is the same, fiber is the best solution for a 400M run. I've never had good luck with long run SDI and I frequently have cable needs that exceed 400M. I run fiber for basically everything and only run SDI for connections to cameras at the end of the fiber.

Best,

David

My experience with the Micro Converters is they had issues with any SDI cable longer than 50' and aren't really designed as boosters and I have no clue if they would even function this way using the SDI through.

50 feet????

Then you're using bad quality SDI. 1694a is rated for at minimum 100 meters at 1080i, and a lot of gear quotes more than 100m at 1080p with that cable.

I'm regularly running 80m-110m runs at 1080i with 1694f (flexible variant of 1694a), have only had to do 50m at 1080p or higher so far.

Appreciate the clarification. I don't use SDI for long runs so it's never been something I've looked into. As I have already posted - for a 400m run I'd say fiber is going to be the undeniable winner. I'd look at renting the gear vs risking 5x5 cables/converters and power locations.

It's interesting that the Micros have re-clockers on the loop output which will allow them to work as the OP suggested.

Best,

David

The Micro Converters as far as I can tell aren't designed as amplifiers.

The 3G Micro converters have re-clockers, SDI doesn't use boosters or amplifiers per-se, a distribution amplifier is a re-clocker. They are used to reshape/reclock the square wave for re-transmission rather than boost or amplify in the analog sense.

Good Luck

time.png

Wouldn't distance be dependent on the cable used? RG6, 59 or 11?

Best,

David

I don't know what a "booster" is, I reckon y'all are referrring to a re-clocker. The re-clocker in theses units should be good for 100m @3G. If the signal is only travelling 50' before pooping out I'd have a look at the cable or termination, something is wrong.

Good Luck

Thanks all for the discussion. As I mentioned in my original post, fibre isn’t an option for us yet hence the question. We are going to do some real-world testing on Monday of 5 lengths of SDI at 85m with 4 micro converters (powered by usb battery packs) to reclock the signal. We’ll be testing across 6/7 hours so I should be able to report back after Monday!

(For those interested, we will be using a mixture of Belden 1694F and Image 1000 Stranded cable)

Wouldn't distance be dependent on the cable used? RG6, 59 or 11?

Maybe, if the cable was the only component involved. But there is a chip that transmits on one end, and a chip that receives on the other end. Some circuits do better than others, and I have many devices (non-BMD) that can far surpass the SDI on paper spec, and a few that don't even come close to meeting it. Don't forget your connectors-are they the correct flavor for this signal? Finally, just because cable is RG-whatever doesn't mean it does well with a digital signal at a given distance. And even if it does, crush the cable by stepping on it in the middle, or let the connector get snagged while you rolled it up last show and that number is suddenly 1/2 of what it was.

At the end of the day, I don't believe any published spec totally, marketing is-well marketing. Do your own tests with the actual gear and see where you get. If it works be happy, if not you'll need another plan. IMO 400m is really asking for trouble on copper.

Fiber is the only real good solution in these cases!!

That many cables and that lengths is just asking for trouble with that many points of failure....