by Henrik’s Blog @ hforsten.com:
Ionizing radiation is something that almost anyone finds exciting (or scary) and I’ve also been for long wanted to build a Geiger counter. Unfortunately Geiger tubes have usually been too expensive to seriously consider buying them just for a hobby project. But I found out that sovtube sold soviet cold war era Geiger tubes only for a couple dollars. I bought one CI-22BG tube and one CI-3BG tube for total of 16€ including shipping from Ukraine to Finland. The site itself didn’t really convince me payment via Paypal failed because of invalid seller email address and gmail warned me that order confirmation e-mail might not have come from the address it claimed. However, I got both of the tubes and they seemed to be okay.
DIY Geiger counter - [Link]
Tom Cousins of DOAYEE made this DIY nixie tube clock:
Below is the schematic for the project, as you can see I’m using 6 IN12 nixie tubes, each with it’s own 74141 nixie tube driver. These drivers are great! They simply connect directly to the nixies and display whatever 4 bit binary number you give them (if you give them anything above 9 they blank the display – hence why I use the number 10 in my code to blank the nixies). Because they take in a simple 4 bit binary number, I can hook them directly up to some shift registers to drive them, in my case I used 3 74HC595 shift registers (available everywhere), because they can be “daisy chained” together, meaning in the code I only have to write one 24 bit binary number and it will display all 6 numbers on the nixies. Though in reality I split them up into pairs and write three 8 bit binary numbers.
Nixie tube clock - [Link]
by Nancy Owano @ phys.org:
Thumb-size vacuum tubes that amplified signals in radio and television sets in the first half of the 20th century might seem nothing like the metal-oxide semiconductor field-effect transistors (MOSFETs) that dazzle us with their capabilities in today’s digital electronics, say two scientists, but it might be time for fresh thinking about vacuum tubes and even some mashing-up for surprising results. Jin-Woo Han, research scientist, and Meyya Meyyappan, chief scientist for exploration technology, at NASA Ames Research Center in California, wrote an article that appeared in IEEE Spectrum on Monday, which details their explorations of a vacuum channel transistor. Their article indicates “vacuum channel transistor” is a phrase to watch in the context of what’s next in transistor technology. The what’s-next conversation is certainly one that continues.
Scientists explore mash-up of vacuum tube and MOSFET - [Link]
The amplifier is based on the 12AU7 valve (part number ECC82 in Europe). The schematic came from here, it’s a nice kit, but lacked a power supply and the layout wasn’t quite what we needed for kits in TinkerSoc. I added a LDO 12v regulated power supply, an input volume control pot and kept the design single layered (with one jump). The final schematic can be viewed here
Tube Amplifier - [Link]
The basis for this tube preamplifier started out as a post in the Super simple single stage tube preamp thread on the website Forum. One of the members (see Mark’s 4S Universal Valve Preamps) had suggested building a Super Simple Single Stage Preamp (“4S” Preamp for short) and there was much discussion concerning various tubes, gain, noise, etc. and several designs were presented using various dual triode tubes. Then the proverbial gauntlet was thrown down with the phrase “switch from 12AU7 to 12AX7″. My answer was to design a universal line stage preamplifier that would work well with an entire range of tubes. Thus was the 4S Universal tube preamplifier born.
4S Universal Preamplifier for 12A*7 Tubes - [Link]
I’ve recently become interested in Nixie tubes. Nixie tubes are neon filled glass tubes that contain cathodes in various shapes, numbers being the most common, and a mesh anode. Passing a current through the cathode causes the neon gas to ionize which makes it light up.
The problem with these tubes is that they voltages of around 170V in order to ionize the gas. Fortunately, most tubes only need a few mA which makes the supply design simpler and easy to run off a wall wart.
A low cost Nixie Tube Power Supply - [Link]
In this mini tutorial we introduce a quick and cheap way to make your own Nixie Tube sockets to use them on your next Nixie project. A socket enables you to change a damaged Nixie Tube quickly and with minimum effort.
- plastic stand-off bases that comes with many of the Nixies
- universal IC socket header
- glue (optional)
- common tools
Haris Andrianakis writes:
This is a project i designed a year ago but never built, because of not enough spare time. This month i found some free time so i started building it and i send the pcb layout for manufacturing.
All started when i received some IV-11 vfd tubes from an ebay seller i ordered from and i started testing and prototyping by first trying to simple light up the VFD tube.
A VFD tube works like a 7-segment led display with some small differences.
A) The Filaments. The Filaments exists to power the tube. We have to supply these two pins with 1.2Volt and nothing more (polarity doesn’t matter).
B) The Grid. The Grid is like the common anode of a 7-Segment LED display. So the Grid has to be pushed high at 60Volt (in these tubes) in order the segments to be able to light up.
C) The Segments. The Segments light’s up simple by pushing them high at 60Volt.
IV-11 VFD Tube Clock Final Design - [Link]
Ante Vukorepa draws our attention to this video of Claude Paillard, a French radio amateur (F2FO), making his own tubes (also known as thermionic valves) from scratch. “The video depicts the whole process, from winding the filament through making the glassware, assembly and vacuuming, to testing. Pretty awesome!”
For more information on Claude’s activities as well as links to articles on vintage radio topics, go to Claude’s website. (In French; if English is needed, click on the Google translate link at the top of Claude’s webpage.)
Homebrew electronic tubes - [Link]
This is a PDF in English published in 1947 and features 45 complete schemes of tube amps, including diagram drawing material list and description of operation. Ideal for anyone interested in old amplifiers (Vintage) and the supporters as well as a modern valve amplifier. The power of the circuits presented in the book ranges from 1 to 75 Watts.
Practical Amplifier Diagrams – Tubes Audio Power Amplifiers - [Link]