Hi Circlotron,
I tried to reproduce your test. I could not see the discontinuities you are showing.
I used a Rigol DG1032Z with firmware 00.00.12. I viewed on a Hameg / Rohde & Schwarz HMO 3002 scope.
Perhaps your generator is on an older firmware? Also, could it be a triggering problem of your scope?
regards, Gertjan.
I found out just now it is only under certain conditions.
Put both channel A and B to 50Hz sine wave.
Both channels active.
Same amplitude both channels.
Channel B 60 degrees shifted from channel A
Go to Utilities and lock together tracking of frequency, amplitude, and phase.
NOW you will see something when you wind the knob and the frequency changes in 1Hz steps.
If you connect it to a loudspeaker it sounds very bad!
If you unlock the phase tracking the problem stops. Very smooth steps.
I will check what version firmware.
Edit -> firmware is 00.01.12 so is newer than yours even.
Edit 2 -> Upgraded to v03.01.12.00.00 2017-09-10
Problem now appears to be fixed!Edit 3 -> Problem still exists.
If frequency, phase and amplitude of both channels are locked together and the phase difference is zero then the problem doesn't seem to happen. If the phase difference is large like 60 deg or 90 deg and b
oth channels are running then the problem occurs when one channel is stepped by 1Hz while outputting 50Hz or so.