I'm aware that the 7L13 50Mhz calibrator signal is stated as -30dBm into 50 ohms, but how accurate is that spec...?
It should be as accurate as the 7L13 instrument itself. Note however that given their age, each 7L13 today most likely requires full calibration to achieve the factory specs. I had to calibrate mine, including the calibrator level. Fortunately the procedure is not very difficult although it takes time and effort.
HTH,
Best regards,
Nenad F.
