We present the current performance of the in situ radiocarbon (14C) extraction line at the University ofBern with an improved extraction and combustion system. After three major steps of improvement, the extraction ofsample CO2gas now takes place inside a platinum crucible, supported by an outer quartz-glass crucible. This setupallows us to operate the line as a closed system for several samples without breaking the vacuum. Measurements ofprocedural blanks and samples from our reference strewn field, Jiddat al Harasis 073, performed in our system all showa good reproducibility and, for the strewn field samples, consistency with published data. We describe eachimprovement step in detail, discussing the advantages and disadvantages of all tested setups. By sharing ourknowledge, we aim to inform and prevent others from making the same or similar detours in establishing14Cextraction systems for extraterrestrial samples.
