Ok, Yea another extender for the Tektronix TM500/5000 test mainframes. The vast majority of 3rd party extenders out there are pure shit (IMHO). Most of these are admittedly designed for low cost hobbyist type applications. I’ve purchased a bunch of these over the years, and to be honest I’ve caused more damage than I’ve solved. Here’s a partial image of the hall of shame for these things:
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High Voltage 100A Active Load with Transient Capability (Part One)
GENERAL
As part of a pulsed energy project, I needed to test a rather large power supply to achieve the desired results (48V @100A). For those that are looking, that’s 5Kw. This article discusses the design & implementation of a hybrid static/transient load testing instrument. This allows static load testing with superimposed transient capability in a single instrument.
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GPS locking a Rubidium Time Reference
In this article, I’ll discuss the implementation of a GPS stabilized 10Mhz. reference clock. For my requirements, the rubidium clock is a Stanford Research FS-275, which can be phase locked to a 1 pps reference. This is further GPS stabilized by coupling a GPS time receiver 1pps sync pulse to the rubidium clock 1pps input. This is primarily for correcting long term drift in precision timing applications. The rubidium crystal will age at a rate ~5e-9 long term, which can be improved to ~1e-12 by using GPS lock.
Installing Python 3.8 as default on Raspberry Pi
Raspberry pi defaults to Python 2.x, so if we want to use python 3.x it needs to be explicitly installed. Pretty simple, follow the steps below and we’ll install from source, build, and set the desired release as default.
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HP 11721A Frequency Doubler Lab Repair
I was looking for a cheap doubler and came across this unit from Korea. It took almost 6 weeks to get here, some sort of customs holdup. This doubler covers an input range of 50-1300 Mhz. My intent with this was to provide an external doubler for my HP8640B. This item was designed by Bob DeVries of HP.
HP 8640B Signal Generator Lab Repair
HP 8640B Signal Generator Repair
S/N 2835A30360
Options 001 003
I’ve been looking for one of these puppies for awhile. I used one of these in my work in the mid-late 70’s, so I’ve been trying to find something broken but newer to bring back to glory. Considered by many as one of the finest signal generators ever manufactured, the 8640B has been around a long time, and its frequency stability and spectral purity is second to none.
Raspberry pi3 Retro Gaming Platform Overclocking
Overclocking
When utilizing the Raspberry pi3 in a GPU intensive configuration, the stock clocking may not be sufficient. This is usually depicted on-screen by flickering, screen lock, etc.. or choppy audio from the HDMI feed.
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Adding a share in Virtualbox
When running a guest VM in VirtualBox, it sometimes is advantageous to be able to share files between the host and VM guest instances.
RALINK 802.1X MacOS Driver
This post contains instructions for installing the RALINK wireless drivers for ALFA external wireless adapter on Mac. Note that the RALINK drivers are necessary on the Mac host when used in place of the native wireless, but NOT required when running the wireless adapter in a Kali linux VM. In that case, the RALINK drivers are provided from the Kali distro.
Please click the link below for installation instructions for the Mac host installation.:
VirtualBox VM Disk Resizing on MacOS
VirtualBox VM Memory Resize
When using VM’s inside VirtualBox, memory reallocation is sometimes necessary, particularly on minimal VM’s whose requirements change.