by Suzanne Deffree @ edn.com:
Texas Instruments announced plans for the Regency TR-1, the first transistor radio to be commercially sold, on October 18, 1954.
The move was a major one in tech history that would help propel transistors into mainstream use and also give new definition to portable electronics.
TI was producing germanium transistors at the time, but the market had been slow to respond, comfortable with vacuum tubes.
However, the use of transistors instead of vacuum tubes as the amplifier elements meant that the device was much smaller, required less power to operate, and was more shock-resistant. Transistor use also allowed “instant-on” operation because there were no filaments to heat up.
TI announces 1st transistor radio, October 18, 1954 - [Link]
Kevin Rye writes:
I’m in the very early stages of prototyping a nixie clock. I picked up some MJE340 power transistors to switch on some IN-3s. I can then use a digital pin on my Arduino to turn on the IN-3s through the transistor. I’ll then have myself a blinking colon for my nixie tube clock.
Flashing a Nixie with an Arduino - [Link]
International Rectifier have announced the introduction of the IR66xx series of high performance 600V ultra-fast Trench-gate Field Stop insulated-gate bipolar transistors (IGBTs). The new high power family of devices features extremely low conduction and switching losses optimized for welding applications.
Utilizing Trench thin wafer technology to offer lowest conduction and switching losses, the new devices are co-packaged with a soft recovery low Qrr diode and feature ultra-fast switching (8 KHz – 30 KHz) with 5 µs short circuit rating. The 600 V IGBTs also feature low VCE(ON) and positive temperature coefficient for easy paralleling.
IR Launch Welding IGBT - [Link]
Open Analog is an organization dedicated to exciting makers about analog hardware. We make popular ICs into transistor level kits!
The first Open Source analog IC kit from Open Analog has been created, assembled, and verified. We call it the SevenFortyFun and it is a transistor level op amp kit. You can finally get the chance to understand whats going on inside those ICs! Now we need your help to proto the next revision (I gotta eat somehow!). This Kickstarter campaign is to raise money in order to print the first batch of PCBs and order parts for production volume.
741 Op-Amp Kit - [Link]
Analysis of the bipolar transistor amplifier at low-frequency is relatively easy, and several calculators exist online that do a good job. For high-frequency operation, there are fewer references available. For my projects, I like to build a reference spreadhseet where everything is in one place. This allows me more flexibility in optimizing the circuit, and is much faster than simulating with LTSpice or similar package. Furthermore, constructing such a tool is a great way of gaining more insight into how the circuit works, and how each of the parameters affects performance.
Common-Emitter and Common-Collector Transistor Amplifier Calculator for High-frequency Operation - [Link]
Electronics DIY published a new build, the Curious C-beeper:
Curious C-Beeper is a fun to build little probe that can be used to quickly detect the capacity of capacitors in pF nF range, test their stability with temperature changes, find broken wires, locate wires, trace wires on PCBs, and to locate live wires behind the walls without touching them. The circuit uses three transistors to make a most unusual capacitance beeper probe. When a capacitor is touched to the probe, the probe beeps at a frequency that varies with capacitance. The frequency change is so steep with capacitance that tiny capacitors may be precisely matched or an exact fixed value may be selected to replace a trimmer in a prototype.
Curious C-beeper - [Link]
electronics-diy shows you how to easily make a mini FM transmitter:
It transmits FM waves so you could easily receive the signals on your mobile phone, radios, etc. As the name and the picture indicates it is very small and is approximately the size of a 9v battery clip. With this FM transmitter you could start your own mini FM station. The circuit uses BC547 transistor to amplify the signal and then frequency modulate it. It uses “frequency modulation” most commonly known as FM, the same principal to transmit audio signals captured by the microphone.
Mini FM transmitter - [Link]
by Peter Demchenko @ edn.com:
Low-current switching regulator ICs often use a Darlington as the output switch. The power conversion efficiency in this case can be improved with the help of only two cheap components. To make this possible, the chip should have a separate pin for the collector of the driver transistor Q1 (Figure 1). At startup, D1 forms a path for the collector current of Q1. Later, D1 and C1 comprise a current-additive rectifier which enhances the collector voltage and current of Q1, hence reducing voltage drop on the closed switch Q2.
Improve efficiency of low-cost switcher - [Link]
by Henrik’s Blog @ hforsten.com:
In my previous post I wrote about a circuit that would change it’s output depending on what was the spice simulations DC sweep range. Today I investigated the circuit a little and I was able to remove lots of components that didn’t affect the bug and this is the resulting circuit.
Metastable transistor circuit - [Link]
IBM has given itself a deadline of 2020 to perfect the nanotube transistor, for which there are significant technological hurdles: R. Colin Johnson @NextGenLog
IBM Will Produce Nanotube Transistors by 2020 or Give Up - [Link]