Posted in general electronics

How to get a desired resistance using standard resistor values

This is easier than expected… (example) type “how can I get 2869 ohms using standard resistors” in Wolfram Alpha and …

Posted in microcontroller

Programming the ATmega32U2

This is a low cost microcontroller, less than $5 in a qty of 1. ATmega ready-made boards are cheap, around…

Posted in mixer radio

Quad FET mixer

Saw this mixer here (google translation – the original website is in Japanese).It looks quite neat! The entire website has…

Posted in transmission lines

Transmission line transformers (TLT)

Worryingly, there are comments here: http://www.eham.net/articles/24502  that are simply wrong, and cause a lot of confusion to people trying to…

Posted in application software linux programming

Writing and running Java programs in 5 minutes: Java error: package com does not exist

For quick development work, I’m not interested in using netbeans or eclipse or some other IDE, but the majority of…

Posted in mixer

Mixer circuits

Most modern mixer information these days concerns the Gilbert Cell active mixer, but these are alternative active mixers, snippets from…

Posted in dielectric constant relative permittivity transmission lines

More dielectric constants

Since these are so hard to find, I’m going to record all findings. According to a 1961 document called Plastic-Film-Dielectric…

Posted in tablet

Tablet cover part 3 (final part)

Edges were soaked with water, and sewed bit-by-bit, clipping it into place after sewing each little bit (lots of clips…

Posted in tablet

Tablet cover part 2

I decided on a book type cover, so the following shape was laser cut in leather.   CAD file is…

Posted in tablet

Tablet cover

A tablet is ideal for portable use, yet it was hard to find a decent case. This is an attempt…