Ping Tool 1.1 does not support the feature you mentioned, we will consider to add "save log file" in the future version, then you can save all history data.
However, you can protract saving times via adjust the Options. Please select "Delay Betwen PINGs" to the max. 10s, then it can keep a 13.8 hours logs. Select "Poll Interval" to the max. 5s, then it can keep a 500 hours logs.