[G0HZU_JMR]

Here's a transient response plot where the current is briefly ramped from about 2.5A to 15A. It shows about a 50mV sag in the 13.7V output when the current briefly ramps up to 15A.

The scope timebase is 500us/div and the green trace is taken from the current sampler in the electronic load.

There is very little overshoot in the plot below. However, when I decrease the risetime of the current pulse (to get a faster edge) there is some ringing that has a 20us period. This might be due to the way I wired the connections to the control board. However, in normal service it would never see a step in current that would be this fast.

I suppose I could take it apart and try and improve the transient response. The 723 regulator has a wide loop bandwidth so maybe it isn't a surprise to see some slight ringing at 50kHz when severely provoked. I think this level of performance is already very good for a low cost PSU like this and the plot below should give you some idea of what to expect in terms of dynamic regulation.