"Mark S. Holden" wrote:

My guess is they expected leaving the parts out of the radios for people who
didn't care about the port would do more for the bottom line than selling the
accessory for those who wanted the capability.

It also should be noted that Yaesu's CAT adapter (or *one* of them if
they did multiple designs) was more than a level converter -- it had
optical isolation to avoid any ugliness with ground loops or the like.

--
Eric F. Richards

"Nature abhors a vacuum tube." -- Myron Glass,
often attributed to J. R. Pierce, Bell Labs, c. 1940