The DTC-100 will only put out HD on the DB-15 or NTSC from the Composite / Y/C / RF outputs, but not both simultaneously. There are Crestron .ir drivers that will allow discrete HD / NTSC mode selection and even aspect ratio mode control, but there is no way that the 2 devices that you mentioned can display video simultaneously.
Solutions... Get a VGA to video transcoder. Extron, Inline, among others, make good units that should give decent results. This is a somewhat expensive solution. There will be aspect ratio problems on certain channels, however.
OR...
Have a second standard definition satellite receiver installed to drive just the NTSC monitor. I'm sure that you would be able to build an interface that would make the presense of 2 different receivers transparent to the user. I guess problems would occur when pay per view shows were ordered.
In my own opinion, and I've voiced this before, high definition receivers do not do well upconverting standard definition material. There is no reason to output high def if you are not watching a high def channel. Another thing with that receiver is that it puts out 540p when it does upconvert. This can cause issues with some projector / monitor / video processor setups.
The other HD DSS receivers that I've used exhibit the same characteristics. Even the new Zenith model says that it will not output HD and NTSC simultaneously. If someone made a box that did, it would justify everyone in this industry to use that box 100% of the time over any other manfacturer's model no matter what... hint, hint.
