Checking an AC-DC Power Transformer as the cause of a device failure

After a couple of personal experiences, I found that many electronic devices that use a wall plug in AC to DC power transformer ( commonly known as a power brick) are the most common cause of failure to the electronic device they are connected up to.
NEVER just check this for voltage. A power brick can easily show you it's supplying the right voltage BUT lacks the Amperage that your device requires. It's usually the amperage that fails.
THIS IS THE RIGHT WAY TO CHECK A POWER BRICK:
Invest in a purchase of a multi voltage universal power brick from an electronics store or Amazon.
Buy one that has voltage adjustments from 3 - 5 - 7.5 - 9 - 12 DC volts
MOST IMPORTANT that this new brick be rated for 2.5 or 3.0 AMPS ( also known as 2500 - 3000 MaH).
It should also be the type which comes with a variety of tips to plug into different devices.
....Before you declare that your electronic device is no good......
Replace the power brick with the new one you invested in.
Adjust the voltage to the same voltage as what was supplied on the original power brick. Install the right tip to properly plug into your device AND MAKE SURE THAT IT IS PROPERLY POLARIZED. On the orig. brick or on your device it shows the proper position of + and - voltage for proper connection. Usually the center is + but check first.
Don't worry about amperage. A 3 amp brick covers just about every need for different devices and your device will only use what it needs. It will NOT over power your device. But again make sure the voltage is properly set.
Now with the brick plugged into the wall and plugged into your device, power up your device and see if it now works. If it doesn't, it's the device. if it does, it's your original brick going out.
What I do is buy a dedicated power brick to replace my test brick so I can use it again for the next time I need to check something.
You'll be surprised at how many times you can salvage your electronic device by using this simple test method.