Author Archives: am1us

Potato Cannon and Chronograph- Part II

s

Details about building a pneumatic-based potato cannon. The more interesting part is its performance assessment. Link to Part I. Link to Part II.

Uncategorized Leave a comment

Tunable LC Bandpass Filter- Part III

s

I’ve just completed the final part of a design document for tunable bandpass filters using varactors. A number of helpful closed-form solutions are included. Link to Part I. Link to Part II. Link to Part III.

Microwave Filter Design, RF Filter Design Leave a comment

4×10 Workbench with Pneumatic Lift

s

I wanted a large workbench with surface dimensions a bit larger than the standard 4×8 foot material I frequently work on. I also wanted it (almost) rock-solid to do some optics-related work. The workbench is very heavy- but I designed in pneumatic lifters so that I can easily put the bench on wheels when I […]

Uncategorized Leave a comment

Potato Cannon with Chronograph- Part I

s

Details about building a pneumatic-based potato cannon. The more interesting part is its performance assessment. Link to Part I.

Uncategorized Leave a comment

Tunable LC Bandpass Filters- Part I & II

s

I’ve just completed Parts I and II of a design document for tunable bandpass filters using varactors. A number of helpful closed-form solutions are included. Link to Part I. Link to Part II.

RF and Microwave Design, RF Filter Design, Uncategorized Leave a comment

Using Companion Models for Time-Domain Simulation of ODE’s

s

Companion models can be used to quickly formulate the solution of simultaneous ordinary differential equations like those associated with analog circuitry. This approach is particularly helpful when this capability must be embedded in tools like MATLAB / SIMULINK / C++. The PDF file is located by following this link.

Digital Signal Processing, Mathematics, Software and Programming Leave a comment

CNC Router & Interview Questions

s

I have just added two new sections, one for my CNC Router related projects and a second one for interview related questions. Both are works in progress.

Uncategorized Leave a comment

Book chapter added on Direct Digital Synthesis

s

Extensive chapter added about Direct Digital Synthesis.

Digital Signal Processing, Frequency Synthesis Leave a comment

Updated Filter Design Documentation

s

Major revision to my filter design documentation 5.74 MB

Mathematics, RF Filter Design, Software and Programming Leave a comment

New Programming Projects 26Dec2012

s

Two new software/programming projects added. One for the design of lumped-element lowpass Butterworth, Chebyshev, and elliptic filters. The second for the design of resistive pi- and tee-pad resistive attenuators. Look at the bottom of the Projects page.

Software and Programming Leave a comment

New Book Chapter

s

I just posted a free book chapter on the site for anyone who has subscribed. The chapter is about 80 pages long and goes into a wide range of topics related to direct digital frequency synthesis (DDS). Definitely worth a read or a place in your reference material as this is not the same DDS […]

Digital Signal Processing, Frequency Synthesis Leave a comment

New Article in Microwaves and RF Out

s

My article in Microwaves & RF finally hit. The web version has a lot of typos in it, however, so you will probably find the PDF version a lot easier read. Follow this link and you’ll see the file link. Thanks for your interest.

Phase-Locked Loops (PLL), Uncategorized Leave a comment

New Article in May Microwaves & RF

s

I have a feature design article that is to be published in the May issue of Microwaves & RF. After it runs, I will post a copy of the complete article in PDF format for easier reading. The article presents several nonconventional methods that can help with demanding PLL designs.

Phase-Locked Loops (PLL), RF and Microwave Design Leave a comment

Approximation for RMS

s

Approximation for SQRT( I2 + Q2 ) with Gaussian Noise Present When a complex signal is represented in terms of in-phase (I) and quadrature-phase (Q) components, a commonly used approximation for the signal root-mean-square (RMS) value is Assuming a large number of OFDM subcarriers in the intended application, I and Q appear to both be […]

Digital Signal Processing, Mathematics Leave a comment

Computing Data Windows Recursively

s

Data windows are indispensable for computing the spectral characteristics of signal waveforms that are not periodic in time. In the context of hardware-based digital signal processing, most if not all data windows are expressed in terms of fairly complex function that are not convenient for embedding in a FPGA or custom ASIC. This memo presents […]

Digital Signal Processing, Mathematics, Uncategorized Leave a comment