Inside the Siglent SPD3303X Precision Programmable DC Lab Power Supply.
UPDATE: There is an even cheaper version, the SPD3303X-E which has 10mV/10mA resolution.
Atten PSU teardown video.
Rigol DP832 teardown video.
Forum HERE
Podcast: Download
Why is my lab power switchboard wired like this? Forum: https://www.eevblog.com/forum/blog/eevblog-1652-why-is-my-lab-switchboard-wired-like-this/ Podcast: Download