Use your common sense!
You are answering your own questions as you post.

"Richard" wrote in message
...
Hi. Is there a standard way to measure antenna bandwith? Is it within
3dB
down of maximum gain, or is it between SWR limits?

I'm looking at an FM receiving yagi that is advertised as covering the
frequency range 87.5 - 108 Mhz. And I'm wondering what this means. Is the
received signal going to be 3dB down at the band edges or what?

I notice that there are commecial yagis (that are probably suitable for
transmission) that have 150-174 Mhz in their description. Yet they are
stated as having a bandwidth of say 1.3 Mhz. What's the deal here?