Let's re-visit the thread which ran back in 2016
on the subject of RF Voltmeters
https://www.vintage-radio.net/forum/...ltmeter&page=3. Inevitably, probes were a key issue in the discussion. IIRC, the objective was to come up with a design for an RF voltmeter which would operate over quite a range (1-150MHz ?) with a sensitivity of a few uV (as achieved by Marconi, Booton et al).
Quite a few published designs were found which claimed to achieve this requirement, but when a number of these were built and tested, serious disappointment was the main outcome. Of course, this is not quite the same as IsquaredR, is looking for, but beware...
If IsqaredR builds the Haigh design, I hope he let's us know what he thinks of it.
B