TVS HD SDI output to CVBS

We just bought a TVS HD for our church and need to feed the output into our existing NTSC CVBS system, so I am looking for a reasonably priced (cheap) converter. The Wiistar one I bought won't handle the 1920x1080p60 output, it seems to think that it is 1920x1080i60.

Any suggestions will be greatly appreciated.

I know, the Blackmagic Mini Converter SDI to Analog works fine for 1080i50 to analog. Looking to the tech specs, it will also work with 1080p signals. So I would give it a try.

If this is to expensive, you may try to cascade a cheep SDI to HDMI und a HDMI to analog converter. There are some models at Amazon, which seems to work...