Adding to the book list for 2015. Lots learned and so much more to learn!
Someone picked my brain the other day looking for a technique to compress language files.
After walking away to think about it… my method was to re-order the ASCII code to the letters by their frequency and the most common words by their frequency.
Where lowercase e is stored as an ASCII value using 1 byte
ASCII e = 0x61 = 0b1100001 = 7 bits
APK e = 0x1 = 1 bit
… this method stores an E in 1 bit. This is similar to the Huffman Code with the addition of whole words being included in the code.
“because” is the 94th most used word in the english language and in this method is stored in 7 bits.
I don’t know if this has been done before… but I would imagine it could compress Language files substantially.
I have thought about a third addition of using the most used 2 or three letter combinations commonly used.
|APK ORDER||APK||LET FREQ||WORD FEQ||APK BIN||APK HEX||APK BITS USED|
Was working on my Micro controller reading and had a need for a calculator to check my work for Successive Approximation of Analog to Digital signals.
WIKIPEDIA: A successive approximation ADC is a type of analog-to-digital converter that converts a continuous analog waveform into a discrete digital representation via a binary search through all possible quantization levels before finally converging upon a digital output for each conversion.
To better understand the behavior of a Passive Resistor Inductor / Resistor Capacitor I built another excel calculator….
a whole semester summed up in one drawing
I’ve been calculating a lot of components in series lately for an ECR255 class. I’ve also had to graph them on impedance diagrams and a power triangle.
In an effort to better understand the math I made a calculator for myself. Here is it for you to use and enjoy. If you see any problems please let me know. It was designed in excel 2011 for mac… there WILL be compatibility issues and I hope they’re minor.
How it works:
You can fill int the info you have in the orange boxes. Once the boxes are filled in the calculator should fill in the rest.
If you need to modify anything else, it’s all dependant on the orange boxes. I suggest a goal seek by modifying and orange cell.
In the 70’s and into the 90’s WBS used a Schadow switch in almost every product they built. Different buttons required different offsets so “GOLDEN RULES” of design were made up so each engineer was on the same page. I found two of those pages the other day and was fascinated. These drawings are both done by hand and are admirable.
Check out Jörg Wuttke, Understanding Microphones
Jörg Wuttke was born in Berlin in 1942. He studied electronics and telecommunications at Karlsruhe University, specializing in acoustics, and was teaching assistant to professor Günther Kurtze, the inventor of the shotgun microphone. He joined Schoeps GmbH as a research engineer in 1970, became its chief engineer in 1972, and is now its technical director.
Mr. Wuttke has been an active member of the Audio Engineering Society for many years, including publishing in the AES Journal and presenting papers and chairing workshops at conventions. In1993 he was awarded an AES Fellowship. Since 1972, he has been a member of the DIN standards committee on microphones and headphones. He maintains an avid interest in listening to music and recording live concerts.
This is a very well respected read as recommended to me by Neil Muncy. At the time I was working for him (in exchange for books and resources) he would not let this one go. Because this book was originally a short run it was available in limited quantities and the used market priced this book at 100$ – 300$
The recently had an AES special where it was $20 off, but I think it’s a little past the promotion. If you were to mail the publisher, they may honor it.
Mine is coming hot off the presses:
I have received your order for Audio Systems Design and Installation,
and will notify you as soon as the printer delivers the first copies.
I had been hoping that would be by Sept. 30, but the printer is still
adjusting proofs so it will likely take a bit longer.