300 ohms for an HF radio?

For many reasons I doubt that.

Common balanced impedances are 150, ~450 and I have seen a few 600 Ohm
RF devices.

300 would be extreme to the limits.

What type receiver is this?

Terry

It is a Realistic DX-160. I had this model as a kid and saw the DX-160
on eBay near by and bought it.

Brian