AM21 not supported on a NON HD DVR

[dod1450]

Why is the AM-21 not fully supported on the a Non HD DVR receiver? I have one attach and works great, but I am unable to power it off when I turn the TV and receiver off. The am-21 power off and on with my HD DVR receiver.

 

[jcrandall]

My guess is the AM21 is always on anyway, just the blue light stays on. Perhaps only the dvr receiver software sends the command to turn the light off.