Info on testing vintage power supplies

On 2019-Sep-02, at 9:35 AM, Alan Perry via cctech wrote: Regarding incandescent bulbs, 12V bulbs can be used on the +5. They tend to be cheaper and more readily available than 6V bulbs. Dual-filament tail-light-with-brake-light bulbs such as the 1034 and 1157 are common and inexpensive. The dual filaments allow for some load variation, the tail-light filament is lower current, the brake filament higher. Parallel a couple such bulbs (and the filaments) for more current. You don't have to buy sockets for them, you can solder wires to the base and contacts. Note the current draw is not a straight linear relationship with reduced voltage. At lower voltage they'll draw something more than the linearly-reduced current level. E.g. for the 1034: @ 5V @ 12V ----- ----- tail 0.35A 0.6A brake 1.2A 2.4A I don't know that you'll find any sort of generalised reference for your request. While some general rules may cover many models, the only way to be comprehensive over such a topic is to understand the principles and then look at the specific design of the supply one is dealing with. For switching supplies, usually only one of the outputs is actually regulated and the others will 'follow' in regulation (designed for a low enough source-impedance-to-load-impedance ratio that they'll be in range if the controlled output is in range). Sometimes lesser-current outputs actually have a linear regulator between the switching transformer and the output.