BM Hyperdeck Studio Minis Flicker issue

Hi everyone,
I have 3x HD SDI cameras (1080p 30fps) which are routing to 3x BlackMagic Studio Minis (inside an IT rack). All cameras have roughly 200-250 ft of coax wires. I have random flickering issues on my signal. It sometimes completely black, sometimes some flickers and sometime no flicker.

While I could see the flicker on BM, I connected wires to a monitor and saw no flicker issues.

I have made sure that BM studio minis have latest driver installed with them. But not what else I could do? What are the repeaters? Would be useful to put one and see if it fixes the issue?


Thanks
Hadi

250 ft only works using high grade coax. Can you post the cable type?
Repeaters can help, if you place them somewhere halfway.

250 ft only works using high grade coax. Can you post the cable type?
Repeaters can help, if you place them somewhere halfway.

I'm using M17/29-RG59 coax cables.

What repeaters do you recommend? I don't know why some repeaters need DC power, and some don't?
Any thoughts on these:
Datavideo VP-634 3G/HD-SDI/SDI 100 Meter Extender for the VP-633
KanexPro SDI-HDRPTPRO SDI Repeater

The last time I used rg-59 was in the analog age... not really the type used for sdi. Are we talking about a security camera instal?

All reclockers are powered. The datavideo needs a separate power injector inline. I'd look on this site. A micro converter sdi-hdmi has a reclocked loop sdi

The last time I used rg-59 was in the analog age... not really the type used for sdi. Are we talking about a security camera instal?

All reclockers are powered. The datavideo needs a separate power injector inline. I'd look on this site. A micro converter sdi-hdmi has a reclocked loop sdi

Thanks for your response, these are cameras we use on our aircraft. I chose rg-59 because it is a type of coax used on aircraft. Is there a coax you recommend? I can't see the site you are referring to.

You are probably better off with a double-shielded low-loss coaxial cable designed specifically for HD-SDI video signals. Something like Belden 1694A or Canare L-4.5CHD would be suitable for transmitting HD-SDI signals over distances of 250 ft.