Transmitting HDMI over SDI

Hello,

I have been in a few situations recently where I needed to run signal over a long distance, between a HDMI sink & source. Mostly I have done this with HDMI over cat v systems but occasionally I have needed to this over SDI.
When trying this with the Black Magic HDMI -> SDI & SDI -> HDMI Micro converters (all 3G versions) I have found issues where the signal makes it to the sink, but will randomly flicker if signal will come through at all.

Any pointers on where I might be going wrong on this would be greatly appreciated!

What is the brand/type number of SDI cable being used and what is the distance?
Also, what format is being sent and at what frequency? 1080i, 1080p, 25, 29, 50 etc?

BMD have an interesting product, Teranex Mini HDMI to Optical 12G. It allows you to choose beetwen SDI and fiber according to distance.

As stated before, good cable is mandatory.

I routinely send signal over 200' SDI cable using BMD's BiDirectional Convertors without issue.

We use proper cable.

How far?
There are new HDMI fiber cables now that not only go further but also faster for cheap prices.