It depends on your budget. Some others recommend used high end equipment. I have some older HP equipment. But I bought a new FNIRSI 100 mHz DSO – digital sampling oscilloscope. It’s much more portable than older scopes, it runs off a 5V charger and does so many more things than older scopes. You can read the RMS & peak voltages, frequency and do Fourier analysis.
For power supplies, I’ve got several HP 6216, 6214 power supplies in a plastic case that’s brittle and shattered into splinters when I took it apart. Avoid these completely!! You can buy new adjustable power supplies from companies such as FNIRSI but they’re switch mode and create a lot of RF interference and electromagnetic interference. I’ve got a few Heathkit IP- series adjustable power supplies but I had to replace capacitors and clean and lubricate the pots.
