[SATLUG] Using computer with tv that has only coaxial input

Don Wright satlug at wricomp.org
Tue Oct 30 23:23:27 CDT 2012

Christopher Lemire wrote:

>My television has Coaxial for input only. My video card has two DVI
>ports. I can use a DVI to vga adapter if needed. I have one. Is it
>possible to play video on my computer and have it shown on my
>television with this setup?

Not easily and not cheaply.

The coaxial input is for broadcast TV, carried by a radio frequency (RF) signal.
Cable TV also uses RF signals, but carries them in the cable as opposed to
broadcast to an antenna. You may have a VCR or DTV adapter with a Composite (RCA
HiFi type, large center hole, body usually yellow) or S-Video (4 small pins)
input and RF (screw on, small center hole) output, typically on channel 3 or 4
for use with older sets.

Your computer outputs a digital video signal designed for direct connection to a
flat panel display. The DVI digital signal is compatible with HDMI TVs and
monitors using a DVI to HDMI adapter. You mention your computer video card also
includes the older VGA analog signal so it will work (through the correct
adapter) with the older VGA displays. Neither of these is an RF signal which
your TV can use, and even the analog VGA signal carries each of the three colors
and image timing information on separate wires. A much more complex device is
needed to convert DVI or VGA to Composite or S-Video.

So while you can throw money and complex connections at the problem, it's much
simpler and just about as cheap to get a newer TV that has HDMI inputs already.

Happy Halloween.  --Don

Be well - or at least have interesting symptoms!

More information about the SATLUG mailing list