The CM7004 will not allow you to watch a recorded program while it is recording a new program. You must wait until the unit is finished recording. Then you can choose a recording to watch.
There is 1 storage device that we currently recommend for the CM-7004.
"Sandisk Extreme 500 series. Model# SDSSDEXT-120G "We have tested a number of Solid State storage devices. The Sandisk Extreme 500, 120GB has consistently provided the best results.
*Enabling basic recording capability requires a USB drive (Flash or Solid State), minimum 16GB and maximum 128GB. IMPORTANT: The USB drive must be a new, first-time use device in order to be properly formatted for use with ConverterBox
Please note; The CM-7004 has been designed as a Digital signal to Analog signal converter. Primarily the CM7004 is used to accommodate older Analog TV's that do not have an HD ATSC tuner, or a Digital display that does not have a Tuner installed.
Secondary to that, it also will record programs. This is an economy set top box and has limited Recording options.