How can I route the cables for my TV in a basement with a "half wall"?
Cinder blocks, like concrete blocks, have voids in the center, hollow areas that make the block lighter while maintaining structural strength. cables can often be routed through these voids.



The hardest part might be finding a void. The blocks are staggered in a wall, but the voids still usually line up. You probably need to cut a hole in the drywall just above the top of the block wall. You may be able to see the voids, or you may need to drill test holes through the lower framing plate until you find one.

What happens next depends on where you are routing the wires and what is below the cinder block wall. You can drill through the cinder block at the base of the wall directly below the void and route the wires to either side of the wall. However, if you are routing AC power cables, they must be encased in an electrical box, conduit or metal raceway if they are in a living area.

You may be able to drill a hole directly into the basement area or an unfinished area (crawl space, etc) depending on what is near the wall and where you need to go for power and connection. If drilling in cinder block or concrete, use a masonry drill.

After you finish bringing the wires up into the drywall area, you can patch the access hole you made above the cinder block.

You need to properly mount any cables leading to the back of your TV. Consider a combination box that handles both line voltage and low voltage.



Supplement based on comment

You could put a combination box behind the TV, route the cables in the wall to just above the cinder blocks. Then put another box in the wall at the top of the cinder block. Cover this box with a raceway adapter.



This box will be a junction box with a blank plate on it, painted to match the wall. Then run a raceway channel down the face of the wall and install another raceway box deep enough for an outlet. If you are running both AC and low voltage, they need to be in approved dual or separate channels and boxes.

You still need to connect to the power at some point, so the raceway channel needs to continue to another conventional junction box.