The Sony RDR-HX780 is a clone of the Pioneer DVR-640, minus the DVD-RAM capability but adding HDMI. As such it uses the Pioneer operating interface. Pioneer followed the design of most other brands, where if a copy restrict signal is detected the machine will lock out recording partially or completely. In your case, it appears to be a "partial" lockout: the tipoff is the alert states "Cannot record this content in video mode" instead of "Cannot record copy protected material." The first can sometimes be worked around by tricking the recorder settings, the second can only be bypassed using a digital video filter (as referenced by tomwil above).
Before describing a workaround you can try, please note you CANNOT (without a protection filter) record this type of protected signal directly onto a standard DVD. If that is what you were doing, it would explain the lockout you encountered. In Pioneer/Sony parlance, "video mode" means "standard DVD format that can be played on anything." When an anti-record signal is sensed, the first thing blocked is recording direct to a standard-format DVD-R, DVD+R or DVD+/-R/W. Recording to DVD-R/W and -R discs is possible if you use a new disc and initialize it to "VR Mode" in the Disc Setup menu, before trying to record.
So what you want to do is trick the Sony as much as possible into thinking it is NOT in "video mode." before recording the problem signal. First, go to the Home Menu, then Setup, then Initial Setup. Arrow down to highlight Recording in yellow. Right arrow to the adjoining menu, and arrow down to highlight HDD Recording Format. Arrow to the right, and select "Video Mode Off" (so that it has a little yellow square next to it). If it is already set to Video Mode Off, leave it that way and press the Home Menu remote button to exit.
You can now try to record the problem video, but must do it to the Sony HDD first (not direct to DVD). After you finish recording, try to use the High Speed Copy mode to copy the video from HDD to a standard DVD-R or DVD+R. You've got about a 50/50 chance of the Sony allowing or refusing this. You engage copy mode by loading a blank then going to Home Menu>Copy>HDD->DVD. Click on the recording as it shows in the title list, press the Enter button when you see the advisory about edit points, then arrow right and down to Next and hit Enter. On the following screen arrow right and down to Next again and press enter. Press enter when you see the yellow Start Copy button. When the copy is finished, you'll be presented with options to create a DVD menu and finalize the disc: do it. You'll then have a normal DVD.
If your Sony disallows all of this and won't open the copy to DVD screens, you're out of luck making a "standard" DVD-R or DVD+R until you get a digital protection filter to hook up between your satellite box and your recorder. You could try to copy the HDD recording onto a DVD-R/W or DVD-R disc you pre-initialize for "VR Mode", this usually works, but VR-format discs will only play in Sony or Pioneer DVD recorders (they won't play in most regular players or computer drives.
You could probably use a PC to dupe the "VR Mode" disc to a regular -R or +R, but that entails various software and tricks to modify the dupe disc into being finalized. If you don't already know how to do that sort of thing, or you have an Apple Mac instead of a Windows PC, save yourself a lot of grief and invest in a video protection filter. It makes life a lot easier if most of your satellite programming is protected: connect the filter once, leave it turned on, then use your recorder normally.
Edited by CitiBear - 10/12/12 at 5:27pm