Rob wrote:
"What would the equivalent diode be for up to 2.6GNz ?"
The microwave SWR meter page reference Rob gives says: "---a good
quality microwave diode would be used ---."

I recall using the venerable 1N23 for many microwave applications. My
ancient ECG Manual says that Sylvania`s ECG equivalent was 1N415C or
1N415E.

The 1N415C is tested at 9375 MHz for a maximum noise figure of 9,5 dB as
a mixer. The 1N415E is tested at 9375 MHz for a maximum noise figure of
7.5 dB as a mixer.

For a meter rectifier, you don`t care what the noise figure is, so
either diode would work just fine as the diodes are otherwise
equivalent.

A generic microwave silicon diode should be fine. The lower junction
voltage of a hot-carrier diode will allow greater sensitivity in a power
meter but may burn out more easily. The silicon diode will withstand 2
ergs.

Best regards, Richard Harrison, KB5WZI