08-10-2016, 12:19 AM
(This post was last modified: 08-10-2016, 03:13 AM by pfeerick.
Edit Reason: forgot to elaborate on weight
)
Nice writeup Mark... I'm sure that will help a lot of new users. Maybe you can make this a sticky topic for this thread?
btw, I think you meant 18-20 above where you were talking about wire gauge... not 18-25 (i.e. A range of 18-20 AWG is satisfactory).
Also switching vs linear, you can usually tell by weight. Most of the adapters that could be considered linear are simply a transformer (and are usually much heaver than switching power supplies), which is why the voltage drops as they are loaded up, as there is actually no regulation. An good example is the earlier modem power supplies, almost all of them (in this country at least) were just a AC 240v to 9v AC transformer.... the regulation happened in the modem. However, this was nowhere as efficient as switching power supplies, and wasn't the best when you needed heavy currents. Plus the dodgier ones got warm and used a lot of power when they weren't doing anything.
btw, I think you meant 18-20 above where you were talking about wire gauge... not 18-25 (i.e. A range of 18-20 AWG is satisfactory).
Also switching vs linear, you can usually tell by weight. Most of the adapters that could be considered linear are simply a transformer (and are usually much heaver than switching power supplies), which is why the voltage drops as they are loaded up, as there is actually no regulation. An good example is the earlier modem power supplies, almost all of them (in this country at least) were just a AC 240v to 9v AC transformer.... the regulation happened in the modem. However, this was nowhere as efficient as switching power supplies, and wasn't the best when you needed heavy currents. Plus the dodgier ones got warm and used a lot of power when they weren't doing anything.