After comparing both manuals extensively, this looks like a reskin of the HMO1202.
Specs are almost identical, some differences (some subtle, some not) :
HMO1202 had switchable 50ohm input. This is not present on RTC1000.
Input impedance was 1Mohm with 16pF +- 2pF on HMO, now 1Mohm with 14pF +- 2pF on RTC.
Haven't found anything else yet.
HMO was made in Czech Republic, can't find if that's still true for RTC.
Maybe I'm old, but I preferred the old look.