When adding a PL-259 connector to a radio that doesn't have one (a radio
that is set up for longwire only), is it OK to just wire it straight in, or
is it best to add some sort of impedance-matching circuit? Obviously the
long-wire connector is going to be high-impedance, while the coax coming in
will be 50ohm.

I often see radios that someone has added the connector. I'd like to add
one to an old DX-150A, just for convenience since my longwire comes into the
house via coax. A already use a MLB between the longwire outside and the
coax; the antenna works great on radios with a 50ohm input.

Any advice? Thanks.

Jeff