Q&A: Per Lundahl (Transformer Design)

Per Lundahl is a multitalented designer who runs one of world’s leading high-performance audio transformer manufacturing outfits, Lundahl Transformers, which is based in Norrtalje, Sweden. After graduating from the School of Physics at the Royal Institute of Technology in Stockholm, he worked as a computer consultant for Ericsson. It wasn’t until he decided to move out of the city that he joined his family’s business, which his parents started in 1958.

Per Lundahl, CEO of Lundahl Transformers

In the April 2012 issue of audioXpress magazine, Lundahl shares stories about the company’s focus and products. He states:

I design all our new transformers. Our audio market is divided into two segments, Pro Audio and Audiophile. The Pro Audio segment includes transformers for microphones, mic pre-amps, splitters, distribution amplifiers, and other studio equipment. The Audiophile segment is transformers for MC phono cartridge step-up and for tube and solid state amplifiers.

Our biggest selling products are two types of transformers for microphone preamplifier inputs. In the Audiophile domain, our tube amplifier interstage and line output transformers are popular.

We constantly develop new transformers based on the requests of our customers. Presently we are developing an auto-transformer for a Chinese company and an interstage/line output transformer for some European customers. The latter will probably be added to our range of standard transformers, available to everyone.

For the very fastidious audiophile, we are also introducing silver wire in some of our transformer types. Initially, the wire will mainly be in our high-end MC transformers, but depending on the response, it is possible that we will extend the silver wire product range.

You can read the entire interview in audioXpressApril, which is currently available on newsstands.

Tube amp transformers

audioXpress is an Elektor group publication.

Q&A: Hanno Sander on Robotics

I met Hanno Sander in 2008 at the Embedded Systems Conference in San Jose, CA. At the time, Hanno was at the Parallax booth demonstrating a Propeller-based, two-wheeled balancing robot. Several months later, we published an article he wrote about the project in issue March 2009. Today, Hanno runs HannoWare and works with school systems to improve youth education by focusing technological innovation in classrooms.

Hanno Sander at Work

The March issue of Circuit Cellar, which will hit newsstands soon, features an in-depth interview with Hanno. It’s an inspirational story for experienced and novice roboticists alike.

Hanno Sander's Turing maching debugged with ViewPort

Here’s an excerpt from the interview:

HannoWare is my attempt to share my hobbies with others while keeping my kids fed and wife happy. It started with me simply selling software online but is now a business developing and selling software, hardware, and courseware directly and through distributors. I get a kick out of collaborating with top engineers on our projects and love hearing from customers about their success.

Our first product was the ViewPort development environment for the Parallax Propeller, which features both traditional tools like line-by-line stepping and breakpoints as well as real-time graphs of variables and pin I/O states to help developers debug their firmware. ViewPort has been used for applications ranging from creating a hobby Turing machine to calibrating a resolver for a 6-MW motor. 12Blocks is a visual programming language for hobby microcontrollers.

The drag-n-drop style of programming with customizable blocks makes it ideal for novice programmers. Like ViewPort, 12Blocks uses rich graphics to help programmers understand what’s going on inside the processor.

The ability to view and edit the underlying sourcecode simplifies transition to text languages like BASIC and C when appropriate. TBot is the result of an Internetonly collaboration with Chad George, a very talented roboticist. Our goal for the robot was to excel at typical robot challenges in its stock configuration while also allowing users to customize the platform to their needs. A full set of sensors and actuators accomplish the former while the metal frame, expansion ports, and software libraries satisfy the latter.

Click here to read the entire interview.

 

DIY Audio Design with Tymkrs

With the growing popularity of embedded design kits and microcontroller-based platforms for rapid prototyping, it’s now easier and more affordable than ever for engineers, DIYers, musicians, audiophiles, and academics to customize electronics applications of their own. The March 2012 issue of audioXpress magazine will feature an interview with two DIYers—the duo behind Tymkrs.com—who do just that. “Atdiy” and “Whisker” provide details about Zombietech.tv, their design interests, and their recent projects. Here are some of their most interesting DIY designs:

  • SidCog Organ: Combine a programmable SID chip from the Commodore 64 and an old Hammond organ
  • Laser Audio Transmitter: Use a laser to transmit audio with a laser transmitter and a solar panel receiver
  • High-Impedance Preamplifier: A preamp designed with a JFET for loud and clean sound

Note: All photos courtesy of Tymkrs. The interview will appear in the March 2012  issue of audioXpress. audioXpress magazine (www.audioamateur.com), like Circuit Cellar, is an Elektor group publication.