Every amateur radio station needs power. Almost every modern amateur radio needs 13.8 VDC.
There are a few types of power supplies; this guide should help you choose which is right for you.
First, avoid all Amazon/Chinese brands! You may save a few dollars on a power supply, but if it shorts or overvolts your radio, you won’t have saved any money. Not all are bad, but you should trust a company that has a reputation for quality.
There are 2 main types of power supplies: Linear and Switching
Linear
Linear power supplies are electrically simple. They have a large power transformer and a set of power transistors. They typically cost more money than a switching power supply, but since they do not switch the voltage, they do not generate as much noise as a switching power supply
Pros
RF quiet
Cons
Expensive
Not as power efficient as switching
Larger & heavier
Best use case
HF station
Switching
Switching power supplies are cheaper, smaller, and more power efficient. The switching may cause RF noise. High-quality models can have an RF offset that may be helpful for mitigating RF noise.
Pros
Cheaper
Smaller
Cons
Can generate RF noise
Best use case
VHF/UHF station for repeaters
Can you use a switching power supply with an HF radio? Sure! That is how I started. It worked!
What size power supply should I get?
That depends on the current draw of your radio.
Most radio manuals will tell you what the maximum current draw is.
A 100-watt HF radio should be connected to a power supply that can output 30 amps.
Should I get a fixed or variable voltage power supply?
If you are only powering your radio, get a fixed 13.8V power supply.
If you are looking for a bench power supply for other electronics, a variable may be acceptable.
For ease of use and simplicity, get a 13.8V power supply.
Some power supplies are listed as voltage adjustable, 11-15V; These are the fixed voltage power supplies.
Here are some recommendations for power supplies:
*NOTE FOR POWER SUPPLIES, CONTINUOUS VS SURGE*
Power supplies list the max surge amps, the continuous is lower (the RS-35 can do 30 amps continuous and 35 surge)
Astron
ASTRON RS-35 – Linear
ASTRON SS-30 – Switching
Samlex
SAMLEX SEC-1235P – Switching
There are other acceptable brands – You can search for those here: https://www.dxengineering.com/search/department/dc-power/part-type/power-supplies
If you get a power supply with enough power capacity, you may want to look at DC power solutions like a Powerpole distribution box.