Is it Really "Digital Cable"?

   It is sometimes hard to know what can and can't be done in home theater.  Between the rapid changes in technology, the technical nature of the subject, and variation in the capabilities of components from manufacturer to manufacturer staying on top of things is a daunting task.  One area that can be especially confusing is that of conversions from digital and analog signals and vise versa.

Digital Cable & Signal Converters

    As an example, let's say you have a cable TV converter (cable box for this article) provided from your cable company that receives the signal they transmit.  If this cable box only has analog outputs, such as composite connections, it does not mean that the cable company is trying to pull the wool over your eyes when they say they provide "digital cable".  What will take place inside the cable box is the digital signal that it receives is converted into analog using a digital-to-analog converter (DAC).  The new analog signal is then output though the composite connections.  If the signal is sent to a device like DVD recorder that needs digital information to create a DVD, the analog signal is converted back to digital with an analog-to-digital converter (ADC) from within that device.

Digital Cable: Can I do this?

    You may ask yourself, is there a way to get the digital information to the DVD recorder through a digital coaxial cable with an adapter of some kind?  The only issue with this is that any adapter would come into play after the DAC in the cable box has already done its job.  Essentially, this would have the same effect as connecting directly to the DVD recorder only now there is an additional element that may increase degradation in the signal.

Inspired by a question from J.T.