Yes. I referred to the Github advice and uploaded changes to the ESP as recommended. The serial monitor test shows that the ESP (IP: 192.168.1.3) it is transmitting valid data to 192.168.1.5 (my server). The router’s address incidentally is 192.168.1.1. Is there any way of checking the server’s onward transmission of this data to the mobile app?
Resolved: My local Blynk server is now fully functional. Strange, but I simply deleted the guage widget in the Blynk phone app and reconnected. Temperature displayed correctly. I did recheck the parameters for the original widget before doing this. Anyway, happy days! Thanks for all those who contributed to this post to get me started.