Cristiano Maker

 Today, I made a simple video demonstrating how the control grid of a vacuum tube triode may work. Essentially, the purpose of a control grid, is to control the flow of electrons from the cathode to the anode of a vacuum tube. So, im my experiment, I put my ammeter in series with the B+ and the tube plate and applied a positive charge from a 9v battery and then I inverted the battery polarity, applying a negative charge. In the first case, It is possible to see the current flow increasing, while in the second case, the current practically doesn't flow anymore. You can see this simple experiment in the YouTube video below: For this experiment I used an early type 30 tube, a 1.5v battery and a 90v stack of 10 * 9v batteries and a couple of wires. Hope you like!

 I live in an old house that has no grounding system. As I do many projects using considerable voltages, like vacuum tube amplifiers, I need at least a grounded wall socket for my own security and the security of my devices. So, as my house is rented, I don't want to request someone to make a full/proper ground installation for the entire house. Instead, I created my own grounded socket. Fortunately, the house as a backyard, so I bought a copper grounding rod and buried it into the backyard and then I took a thick wire from it to the inside of the house and made a connection to the ground pin of a "female" socket and I'm using it for my projects. Below, there is a simple video showing the efficiency of that system I made: You you have a similar situation as mine, you can do something similar.

 Maybe you don't know, but you can use a car wiper motor to power your low speed / high torque project. For example, I used this kind of motor to power a ball mill I made some time ago. All you need is a used wiper motor, a computer ATX power supply and 2 wires. The first step is to find what is the low speed connection of your motor. Usually, it is a connection labelled with "53". If you can't find this in your motor, please take a search on the Internet about that for your specific motor brand / model (you can search also by the vehicle brand and model from which you got the motor). Then, as the 12volt supply, we will use any yellow wire from the power supply, and for the negative (ground) you may use any black one. Is simple as that, just connect a yellow from the power supply to the low speed connection of the motor (53 code) and the black wire to the ground connection (this could be simply the any metallic part of the motor). Please take also a look the the YouTu...

 One of my passions are antiques, specially if they have some engineering or electronics envolved. Since I was a child, I had contact with antiques from my grandparents, and one of the things I remember is an old kerosene pressure stove. Some time ago, I decided to buy one, just for decoration, but I also love to keep things working, if possible, so, I decided to turn it on, and made a simple tutorial on how to start it. I made a vide that is available on YouTube, please check it below: I added some subtitles to the video so you could understand better, but I'm also going to write it here: 1 - Put some kerosene in the tank 2 - Fill the small cup below the head with alcohol (+ 90% is good) 3 - Light up the alcohol and let the head warm and start vaporizing the kerosene 4 - Once you feel the pressure increase, give some pumping to help it increase even more 5 - The kerosene vapor will light by itself with a beautiful blue flame (if you need more pressure, pump it more, for less, rele...

 After my first tube amp , I decided to try a battery powered one. There is not a lot of information about guitar tube battery powered amps on internet, but I found some resources. My search began on YouTube and I found a video of a guy that wrote the schematic link in his video description here . I just followed it, mounted the components of the amp (all point-to-point wired) inside a large tin can and used my small 6 inch speaker connected to it. The amp is powered by 10 x 9v batteries ( for tube plates ), one 1.5v battery ( for tube filaments ) and 3 x 1.5v batteries in series, providing 4.5v of negative bias. The tubes used, are one 1Q5GT and two 1T4, early used in battery powered radio receivers. It has just two controls - volume and tone. Here is the schematic: Here is the power supply schematic: And here, the built amp: Check out my videos on YouTube of this amp playing a song from my computer and also a song from my guitar: Hope you enjoy and if you plan to make an amp li...

 One of my favorite electronics projects are metal detectors. I'm trying to build some famous and more complex detectors like the TGSL (VLF) and the Delta Pulse (PI) but I also decided to try a very simple approach - using an Arduino and a few electronic components. As I also work with programming, it was very interesting to join the 2 areas (electronics and IT). The detector works as an "educational" purpose as it detects a large coin at about a 3-4 centimeters distance from the coil while professional detectors can detect objects at a very larger distance, although it can be a great opportunity to learn more about how metal detectors work (in this case using the Pulse Induction technology). I found this project in a YouTube video, and it is not created by me but I'm sharing it with you. In my test, I replaced the LED with a piezo buzzer, so, the components I used were: - 1x Arduino UNO - 1x protoboard (optional as you can mount the components any other way) - 2x 220...

 This is one of the most essential safety devices you must have if you work with electronics. Not only for the safety of the device you are making/troubleshooting but also for you and your electric installation. It is a famous device - the light bulb current limiter also know as dim bulb . The construction is very simple, that's only a high wattage bulb connected in series between your device and the wall. Here is the schematic: I recommend to use a high wattage filament bulb, like a 150w or 200w, usually the rule is to use a bulb with a higher power than the device do be tested. Please not that the wattage must be the real and not the "equivalent" as we find in modern fluorescent lamps. It is mainly used as a "detector" for short circuits: if your device has a short it will draw a lot of current from the mains and the bulb will be as bright as it can, limiting the current because itself will convert the energy into light and hot. If the device has no shorts, th...