> I understand that there is a problem in the silicon of the 16C73 and 16C74
> which means that you should never use BRGH=1 in the serial port.

That is correct


> Could anyone confirm that and advise if this problem is resolved in the 16C74A

It is fixed in the A version


> Anybody know what the problem does?

You may get errors in your transmission.  I've heard several different
error-rates;  from one error each 30 byte to one error each 100 byte.  I'm using
this mode myself in a project, and I have never gotten any errors...


-Dag S