[Amps] Dummy Loads & Wattmeters

[Dr. David Kirkby]

Gary Schafer wrote:
> I would like to have a modern VNA. You should be able to do a pretty good
> job with it. But most hams at best only have access to the older stuff.
> While it is not too bad and can make some pretty accurate measurements it
> must all be in cal to start with.
> I even have some of the old Fluke resistance calibration equipment and while
> it is pretty good it is a pain to use while checking everything several
> times to get it right. Modern and even not so modern high end voltmeters
> will run rings around the older cal equipment.
> 
> As far as I know Bird used the calorimeter method to do their wattmeter
> calibrations.
> 
> 73
> Gary  K4FMX

Bird might well have calorimeters, but I very doubt they would use them 
routinely for calibrating meters.

I suspect they use a Marconi/HP/Agilent/Boonton power meter and attenuator to 
routinely do it.

I do not know for sure, but I suspect unless you put a lot of effort into the 
design of a calorimeter, it would be *less* accurate than professional RF test 
equipment of the sort already mentioned.

Dave