Happy 2018 and project summary over the year.

Not so long ago we were happy to report annual progress of year 2016, and now another year already passed. As usual, we have more content published, and looking forward for future experiments and new technology. Year 2017 had big focus on metrology area, with multiple publications showing very expensive and specialized instruments and tools. xDevs.com site was created and first published a decade ago, in 2008, and continue to be 100% ad-free experimental project to support engineers and share their electronics engineering knowledge. It was not always easy, nor cheap to have new content and projects, but there are no changes in that respect.

Brief summary of the offline activity:

  • Improved resistance measurement uncertainty to <4 ppm level (0.0004%) for 10 KΩ, using special Fluke FSL935 prototype resistance standard.
  • Fixed Fluke 5790A AC Voltage Standard for 3rd party.
  • Created new precision DC Voltage Standard module, xDevs.com “FX” to generate stable 10.0000 VDC.
  • Sold three of Keithley 2001’s back to community.
  • New articles, reviews and repairs were performed and uploaded.
  • Our metrology contributor Todd created six more articles and started 7V LTZ1000-based “MX” design.

New content on site

Full list of all new articles in 2017:

Fluke 5790A AC Measurement Standard repair Illya
Fluke 5450A Resistance calibrator – in progress Illya
Fluke 792A AC/DC transfer standard repair Todd
Fluke 732A service and modifications – in progress Todd
Fluke SL935 resistance standard prototype Illya
Fluke 719 30G pressure calibrator : short review Illya
Keithley 6517 Electrometer / High-resistance meter repair Todd
Calibration of Keithley 6221 AC/DC low noise current source Illya
Keithley 7168 nanovolt switch card and it’s use with RPI Illya
Evaluation of modern pressure sensors with digital interface Illya
Project 792X – 10V FX reference and Fluke 792A support pack Illya
Design of MX voltage reference system Todd
Tale 3 : Testing VK5RC’s LTZ1000 reference module Illya
Analysis of the Fluke 8846A custom laser-trimmed resistance networks Todd
Study of temperature coefficient on 150 precision resistors – ongoing Illya
Overclocking for Raspberry Pi 3 Model B Illya
OC Guide for EVGA X299 DARK motherboard Illya
Extreme OC Guide for EVGA GeForce GTX 1080 Ti KINGPIN Edition graphics card Illya
Extreme OC modifications for EVGA GeForce GTX 1080Ti FE Illya
Open-source Intel Core X-series CPU delid tool Illya
Another HP 3458A repair and Dallas NVRAM replacement to RAMTRON FRAM TEKTRON

That’s total 21 articles added, with few more still in works. If you interested in ultra-high performance equipment voodoo, be sure to check Fluke 792A AC/DC transfer standard repair and Fluke SL935 resistance standard prototype.

Appreciate support from community and especially, Todd. We already have lot of plans for 2018 to do even more content.

Raspberry Pi Foundation had contacted us (Kingpincooling.com/xDevs.com team) for overclocking experiments with RPi and publication in Hackspace magazine Issue 1 about Overclocking for Raspberry Pi 3 Model B. It was fun little project.

Offline events and our own calibration setup.

After a succesful assembly and test of Fluke SL935 Resistance standard is was sent to calibration by Process Insturments in USA, 28 November 2017. These guys did great job getting Fluke SL935 1 Ω and 10 KΩ calibration in November 2017.

Together with Fluke 732B this prototype can fit Fluke 5700-series calibrators needs very well, providing ultra-stable 10 VDC, 10 KΩ and 1 Ω at sub-ppm stability levels.

Also exclusive set of 10 pcs xDevs.com FX DC references will assembled, tested, calibrated and shipped to selected people in 2018:

montemcguire – 1 unit [CONFIRMED]
dr.diesel – 1 unit
chriswebb – 1 unit
PeLuLe – 2 unit [CONFIRMED]
Todd – 1 unit [CONFIRMED]
bck – 1 unit [CONFIRMED]
USA 2018 cal club – 1 unit [CONFIRMED]
CalMachine – 1 unit [CONFIRMED]
zucca – 1 unit [CONFIRMED]

Prototype board photo:

3 week long data log with six older xDevs.com KX 7V references and two 10V FX references, using HP 3458A and “Keithley 7168 nV-scanner”:

Few shipments were done to maintain lab accuracy on DCV and OHM measurements.

This allowed to verify absolute accuracy with ±1ppm for 1-10 VDC ranges and ±2.4 ppm for 1-100 KΩ resistance ranges, with HP 3458A/Keithley 2002 quattro. Plan for 2018 is to extend accuracy also for alternating voltages, using Todd’s acquired Fluke 792A.


During 2017 our website visited 97546 users, with over 8.0M page views. There is no target to capture most views/clicks, no staff involved in full-time project development, so I reveal these numbers just for curious minds.

Focus is still to keep high SNR-level on specific niche content we publish, instead going all about broad-topic talks for wider audience. Main focus this year was on high-end test and electrical calibration equipment, such as voltage standards, multi-function calibrators and long scale DMMs.

I also added few more videos covering electronics on my YouTube channel, which got over 650 subscribers :).

There are still lot of things to do and improve, so looking forward to next year, targeting to provide even better quality content. Key focus area next year is to work on our own project designs and cowork with other hobbyists, with much more valuable how-to’s and content to be published online! Contact me directly if you have any questions. Every comment matters ;)

Also we are available at IRC chat server: irc.xdevs.com (standard port 6667, channel: #xDevs.com). Web-interface is here.

Happy New 2018!

Ilya Tsemenko
xDevs.com Project

Author: Ilya Tsemenko
Created: Jan. 1, 2018, 6:26 p.m.
Modified: Jan. 1, 2018, 9:42 p.m.