[Electronic M]

Not enough room inside the case on almost all portables. About the best you could do is find a DTV converter box that's small and uses a wall wart of the same or lower voltage than the batteries, hook it in to the sets internal batteries, hot glue or tape it to the TV, connect the TVs whip antenna to the center lead of the antenna input on the converter box, then connect the TO TV coax on the box to the external antenna input of the TV (or where the whip used to connect on the TVs PCB, and have an ugly kludge...Also ATSC 1.0 sucks for any application where the antenna moves so you'll loose signal if you try to walk with it, use it in a moving vehicle, wind blows the antenna, etc. ATSC 3.0 is supposed to be better for mobile use but hasn't fully deployed yet, converter boxes for it don't support analog TVs and cost 3 figures.

I don't use my analog portables as away from home sets because of the downsides of mobile DTV reception and instead use my laptop and a tuner dongle for field use...I could use a portable DTV set if I wanted but the dongle was cheaper and uses less space when not in use.

How I use my portable analog sets within a block of home is by connecting the composite audio/video output of a DTV converter box or any video source I choose (in practice about 90% HDMI output of my media player PC and Roku down converted to analog) to a Blonder Tongue AM60 agile modulator feeding an antenna. The Blonder Tongue acts as a low power analog TV transmitter and any TV on my property or the block for that matter (when output is set to max) can tune it.