dave wrote:

On 01/23/2014 06:45 AM, Michael A. Terrell wrote:

dave wrote:

On 01/21/2014 03:04 PM, Michael A. Terrell wrote:

dave wrote:

On 01/21/2014 07:24 AM, Mike Tomlinson wrote:
In article , Jeff Liebermann
writes

http://www.learnbydestroying.com/jeffl/crud/asus-k501j.jpg
The "hole" in the burnt out component is characteristic of applying
reverse polarity to an active device such as a diode. I would guess
that the diode exploded, blowing the top off the epoxy package.

The 8-pin IC next to it also looks burnt.

To the OP: forget it, this is not economically repairable. Buy your
daughter a new machine and use the correct charger in future.


A diode is not an active device.


Then explain the Gunn Diode. DC in, RF out. How about LEDs? DC in,
Photons out.



An active device is any type of circuit component with the ability to
electrically control electron flow (electricity controlling
electricity). In order for a circuit to be properly called electronic,
it must contain at least one active device. Components incapable of
controlling current by means of another electrical signal are called
passive devices. Resistors, capacitors, inductors, transformers, and
even diodes are all considered passive devices.

http://www.allaboutcircuits.com/vol_3/chpt_1/2.html


How does the Gunn diode oscillate without gain? How does it have
gain, if it isn't an active component?


It is not a switch or a valve.


It's a solid state diode that oscillates. DC in, and ~10 GHZ out.
Search on Gunnplexer. You see them on automatic doors in almost every
store. A microwave mixer diode takes a sample from the Gunn diode and
compares it to any reflected signals. This results in a low frequency
signal that is detected, amplified and signals the door to open. How can
a passive diode do that?


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.