Thanks George,
i made a fault entering the passwords.
One has to confirm with "ENTER" and not "SELECT".
Was not aware of this difference, noticed it when reading the original Manual.
I managed to unlock the device with the default passwords.
Changed level 1 password, so it is written to eeprom, bit error "EEPROM checksum" is still there.
Output fed to oscilloscope shows more than one frequency. Unfortunately i don't have a spectrum analyzer.
Error 501 and Error 502 "Fractional-N loop low, Fractional-N loop high" also still there.
I'm unsure if i shoul investigate in this errors first or if they are a follow up from the eeprom fault...
Dave DL2MDV