Testing

J-Pole Antennas for Ham Radio

If you’ve read any of my other posts, you know I love to build, tinker, and hack at stuff. Antenna-building is something I’ve not made a foray into, until recently. I have a dual-band handheld radio for the 2m and 70cm bands. The so-called rubber-duck antenna that comes with it performs ok but it isn’t ideal. I could get into my local repeaters which are about 10mi away with enough power to break the squelch, but my audio was weak…

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Better JTAG on the Cheap with the FT232H

A couple of weeks ago I wrote a post about using the FTDI FT232R as a cheap JTAG debugger. I’ve been using it for a bit now to play with my Raspberry Pi 3B, and now that my code size has grown, the FT232R is just too slow to cut it. Here’s a breakdown: on the FT232R, the max speed I can set the adapter to is 3MHz. This has given me a transfer speed (loading via GDB) of around…

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Raspberry Pi

JTAG On the Cheap with the FTDI FT232R

JTAG 101 What is it? JTAG stands for the Joint Test Action Group, and the TAP or Test Access Port this group defined is one of the most (if not the most) common way to program and debug embedded devices and computers of all flavors. For the professional, JTAG devices are bountiful and usually not too much of a strain on the commercial budget. But for the hobbyist, things aren’t so peachy. A Segger J-Link EDU can be had for…

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Network bandwidth testing with iperf3

Everyone knows how to use speedtest.net to test your internet connection speed, but how do you test your LAN bandwidth?   When you want to troubleshoot speed issues on your LAN, what can you use? Luckily, some clever software call iperf3 can help us out.  You can find the tool at the main website for iperf and iperf3  here. This tool is available for Windows, Linux, Mac, Android, and iOS, so you’ve got options. There are two parts to testing your network with iperf3. First…

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