Recording limits on my CM7004 ConverterBox
*Enabling basic recording capability requires a USB drive (Flash or Solid State), minimum 16GB and maximum 128GB and must be formatted to FAT32. IMPORTANT: The USB drive must be a new, first-time use device in order to be properly formatted for use with ConverterBox. External USB Hard Drives do not work with the CM7004. External SSD drives that use SLC Flash, work well.
On an average, the CM7004 uses about 6GB for a 1 hour recording of HD (High Definition) content. That equates to about 20 hours of HD content on a 128GB Flash Drive. (Only 117GB used for storage.)
SD (standard definition) content uses much less recording space than HD content. You can average about 3 to 7 times as many SD programs compared to HD programs.
Every TV station can transmit its signals at whatever Bit Rate they choose. Highest bit rate tops out at 17Mbps. The HD signals and the SD signals share the broadcast/transport stream. e.g. If they send the 'primary' HD signal out at 12Mbps, then they have 5Mbps available for the 'secondary' SD channels. The transmit bitrate used for a certain channel can change at any time. This is why it is not possible to provide a set number of hours of recorded programs, that can be stored on any certain sized storage device.
There is 1 storage device that we currently recommend for the CM-7004. However, any USB storage device that uses SLC Flash and is formatted to FAT32 should work very well.
"Sandisk Extreme 500 series. Model# SDSSDEXT-120G "We have tested a number of Flash/Solid State storage devices. The Sandisk Extreme 500, 120GB after being formatted to FAT32, has consistently provided the best results. (It uses SLC Flash. Most USB storage sticks use MLC Flash. SLC Flash processes data much more quickly than MLC Flash.)
When you first insert the properly formatted SSD or USB Flash Drive Storage device into the CM7004, a dialog box will appear on your TV screen 'Setup in progress'. Once installed and you see 'Setup Complete', you can begin to use the DVR function's.
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.