Electronics repairs & projects, test gear, practical demos & software dev....

I buy faulty gear, fix it, and share what I learn. Your support helps me keep going.

YouTube  ·  Odysee  ·  X (Twitter)  ·  My Github  ·  Contact

Got faulty test gear you don’t want—or going cheap? Contact me and I’ll give it a second life and make a YouTube video of the repair.

  

PDVS image

PDVS / PDVS2 / PDVS2mini

I'm the original designer of the PDVS family of Precision Voltage Sources.

PDVS2mini now produced by WryTech.

For PDVS or PDVS2 support, contact me.

I post on X (@IanSJohnston) almost daily—follow for what I’m up to.
Enjoy my work? Donate via PayPal or Patreon.

News....

May 2026 — Added new sections to the website's menu buttons above. Gotta love Joomla Version 6


March 2026 — New web & email server live, all software updated, security enhancements applied and earning a solid B rating on Mozilla HTTP Observatory for strong security headers. Monitored 24/7 with frequent full backups. Btw, I have another website on the server - www.ianj.net

Latest....

Video Blog 185 - HP 3458A 8.5 Digit Multimeter Repair - Part 1

I acquired a faulty 3458A quite cheap in order to try out an A3 board U180 replacement (called the NU180) which fixes catastrophic & expensive drift problems on these meters.
Date: 06/06/26

Video Blog 184 - ADCMT 6243 Front Panel Replacement

A very kind donation from a Japanese subscriber, Haruki (Technical Service, Japan) sent me a replacement front panel!
Date: 03/06/26

Video Blog 183 - Fumeclear FC-2001A Fume Extractor Review

I saw these units on Facebook and liked the look of them so contacted the manufacturer and acquired a review item, the FC-2001A.
Date: 27/05/26

Video Blog 182 - Keysight 34401A 6.5Digit DMM Repair - Mega Quick Repair

This Keysight 34401A came from a working business, the note on the top of the unit explaining the fault. I recognized what the issue was immediately and caught the fix on video.
Date: 15/05/26

Video Blog 181 - Agilent 34401A Multimeter TFT Conversion

Off the back of my other TFT upgrades some folks asked for the HP/Agilent/Keysight 34401A, and I just happened to have one that needed a better display since the VFD was quite worn.
Date: 13/05/26

Video Blog 180 - Agilent 34401A 6.5 Digit DMM Quick Repair

Written on the top of the unit "Do Not Power Up"....what could be wrong?
Date: 24/04/26

Video Blog 179 - Dataman S4 Programmer Repair

Doesn't power up and when it does it doesn't retain it's library ROM.
Date: 16/04/26

Video Blog 177 & 178 - Fluke 8846A Multimeter Repair/Revisit

I last had an attempt at repairing two 8846A's 3 years ago, and in this video I revisit one of them.....can I fix it?
Date: 27/02/26 & 28/03/26

Random Video....

Article link: Video Blog 107 - Fluke 8846A 6.5 digit Multimeter Repair