Monday, December 30, 2013
Sunday, October 13, 2013
Tuesday, August 13, 2013
I soon noticed my 20 month daughter affinity to vehicles. I wanted to give her one where she could sit and enjoy the ride, but currently most powered vehicles for infants require they are able to reach the throttle pedal and properly handle the steering wheel. So I figured out the best way would be to go remote controlled. As I already had done previous projects involving RC gear, it would be piece of cake to turn a regular electric car into a large scale RC car where a small kid could sit inside.
Tuesday, June 11, 2013
From this point on you can also link to this blog via:
(No, it's not com, it's co).
Thursday, May 2, 2013
In spite of already being a working device, there were aspects that like I explained in the previous post, required some attention. One of the major fixes was the voltage drift. This was caused by the 5 K potentiometer used to set the voltage end point. It was too large (the sweet spot of my setup was around 500 Ohms), which besides making it difficult to adjust, caused temperature induced resistance drift to be too large, causing an increase of around 200 mV from the initial voltage once the temperature settled.
Sunday, April 28, 2013
Tuesday, April 16, 2013
Prior to assembling the definitive power supply circuit board (i.e. the main electronics featuring the LM723) I took the time to set it up on a breadboard. Before that I finished the board containing only the large components such as the filter capacitors and the high wattage resistors (current shunt used by the regulator chip to sense the current across the power rail, and a bleed resistor for the output capacitor):
Sunday, April 7, 2013
Another weekend have passed, and along with it a few more results as I slowly but steadily walk towards completion of the project. The digital voltmeter/ammeter displays have still not arrived from China. This is the last piece of hardware missing. Adding time to the equation and all the elements necessary to complete the project are available.
Friday, April 5, 2013
Monday, April 1, 2013
Friday, March 29, 2013
In this previous post I had the chance to present and tear down my old custom-made power supply. It worked flawlessly for about 10 years. I decided to buy a new linear lab power supply because I needed something better with more features such as constant current operation and digital display of both voltage and current.
Thursday, March 7, 2013
My first and accidental attempt at receiving images from a weather satellite was surprisingly very succesful. However as I only started capturing the RF signal late in the satellite pass, it was only possible to retrieve a small portion of the transmitted image.
Sunday, March 3, 2013
Before the Internet, anyone willing to independently obtain satellite imagery from the source would need to buy expensive equipment capable of decoding the analog slow scan video images transmitted by weather satellites such as the NOAA APT ones. Today there are four of these NOAA satellites still operational, the NOAA-18, 17, 15 and 19. All of these are sun-synchronous satellites, which means these orbit the earth at around 800 Km of altitude and cross every latitude at approximately the same mean local solar time for each pass. This kind of orbit is useful because of the consistent illumination (by the sun) of the target upon each pass.
Monday, February 11, 2013
In a recent past I have been very active blogging about this project, which have occupied a portion of my free time in a rather pleasurable manner. After a period of pause I thought of bringing this project back to life, but not without providing an overview of what have been done.
Sunday, January 20, 2013
This have been for about ten years a loyal companion in my electronics projects. And greater than that the fact that it was itself one of my first projects. After that time it still works like a charm.However I thought it was time to replace it with a PSU providing more functionality such as constant current and digital displays.