"jim" wrote in message
...
On Jan 31, 5:54 pm, pp wrote:

Unless you are in the UK where triple scale hydrometers made after
1983 seem to feature a different version of PA to anyone elses heh
heh...

I think the only change was to the temp standard used for calibration.
I still have the older ones that used 60f as the standard. I think
most of the newer ones use 68f as the standard. The standard used
should be printed on the each hydrometer. Temp compensate and
you should end up with the same numbers.