The regs were quoted a couple of messages back and it says - exerpted:
1. 50 watts ERP
2. And defines a dipole as shall be considered 0 dBd for the purposes
of this regulation in defining ERP (as opposed to the usual 6.14 dBi
over average ground)...

Now, typical of anything the feds define, it will be unintelligible...
It is clear to me that the intent was to define the dipole as having a
power gain of 1 (one) for the purposes of defining what constitutes 50
ERP when driven with 50 watts...

So, one might assume that it means that 50 watts into a dipole is
considered 50 ERP - but it does not say that,,, It says for regulatory
purposes that the power gain of a dipole is considered to be ZERO...
Which means - as I my math teacher proved - that 50 X 0 = 0 - per
the regulation...

No it does not!!!

It says that the gain is zero *dB*, to convert from dB to a linear quantity,
which you can multiply, you must divide by 10 and then take the antilog.

So 0/10 = 0,
and antilog 0 = 1

So your sum is actually 50 X 1 = 50, not 50 X 0 = 0

It is much easier if you work in dB where you just have to add or subtract.
50W = 17dBW
so 17dBW plus a gain of 0dB = 17dBW

73
Jeff