Another Sencore cr70 calibration question

[4thdoctorwho]

I recently bought a cr70 and was going through the field calibration/test procedure and I have a question that I hope someone can answer.

Regarding the first two steps of the field test procedure where you are supposed to get greater than 350 volts. My question is once you press and hold the rejuve button, does the voltage remain steady? On the first two steps the voltage initially reads -400V then starts dropping fast to well under -300V. It can go down to the 250V range. Is this normal?

Any help would be appreciated.
Thanks,
Tony