DG4000 Calibration Restoration:
I just finished calibrating my DG4000 for Channel 1 and 2, and the frequency response is flat up to 200 MHz and well within better than +/- 0.8 dB.
So what is calibration? I have concluded that it is removing the un-calibration that you end up with after you install the firmware patch to extend the frequency!
So to calibrate (or rather restore the previous calibration of) your DG4000: Press - Utility, Test/Cal, Secure Code, (put in PW) 2010, Enter, Secure OFF, (the result should be) Secure ON, Access gained.
Then for Cal. select HFLAT, Call Point (start at HFLAT 1-1), Measure Value, Input Value, press Save and wait for it to complete (about 3 seconds), select Cal Point for the next step. Repeat for all 60 steps. Then your done and you didn't have to connect anything up to your DG4000, except for AC power. Hi
Repeat for the remaining channel (only if you find it necessary, but I don't think that it will be).
Cheers, Ted