[JT118]

Werk, As you say it is nothing to with the WD sketch but I do not see where this is in the RX sketch.

But Wizza must alter his TX config from;

*/
#define COLLECTOR_TYPE 0.200 // Please note: Values must be in metric units. Max. resolution: 3 decimal digits
// --------------------------------------------------------------------------------------

TO:

*/
#define COLLECTOR_TYPE 0.229 // Please note: Values must be in metric units. Max. resolution: 3 decimal digits
// --------------------------------------------------------------------------------------

If he does not he will always be reading less than 18mm when 20mm has fallen an over 10% error.

As you say cumulus will not necessarily reflect this on one tip but it will sort itself out after a number of tips.

"This will also happen if you set a Collector Type of 0.22mm. On the first click Cumulus will show 0.2mm not 0.22mm, on second click 0.4mm, instead of 0.44mm, and so on... but as said the total rain value, is recorded on log files correctly. "

Alternatively break the seals and do the considerable amount of adjustment to get exactly 6.28ml in each side of the bucket tip and 628ml of water to represent 20mm of rain on the readout. Then keep the TX config at 0.200. ( I would not do this unless something is obviously out which from the photos it does not appear to be, and it is very much easier through the software.)