Digital energy saver boxes that claim to reduce your power bill by up to 50%, are… SPOILER ALERT: Complete bullshit. Forum HERE

A look at three major products in this lengthy Mailbag. SPOILERS: LabJack T7-Pro Multifunction DAQ with WiFi, Ethernet, and USB 15:56 Balena Fin Raspberry Pi Compute module industrial computer 29:29 Dodgy truck LED tailight assembly 38:00 Joulescope: Precision DC Energy Analyzer Kickstarter With lengthy discussion on current measurement autoranging. Forum HERE

Dave bought a 6.5 digit Phillips PM2534 on Ebay for $140 delivered. Did it even survive the shipping? $200 Ebay 6.5 digit DMM video: https://www.youtube.com/watch?v=I2HcJ80OyrA Forum HERE

How good is your existing oscilloscopes FFT function with the $10 DIY EMC H-field probe compared with a dedicated spectrum analyser? Dave tries the DIY EMC probe with half a dozen different low cost scopes, so it turned into a bit of a practical FFT shootout: Rigol DS1054Z Siglent SDS1202X-E Keysight DSO1204X Rohde & Schwarz ...

A comprehensive tutorial on room (space) heater technology and their effectiveness and efficiency in heating rooms and homes. The different types of heat transfer are discussed, along with the different types of heater technology available and how they apply to room and object heating. The 2nd law of thermodynamics, and the impossibility of new graphene ...

Busting the SOLUS Kickstarter – “The Most Efficient Radiator In The World” based on “completely new, eco-friendly and graphene-based technology” “Save over 80% on your next heating utility bill”! TLDR; It’s a crazy expensive 200W – 300W glass panel heater with magic woo-woo graphene paste that does not produce any more heat than any other ...

Will this dumpster 500MHz 4 channel Tektronix TDS540D scope work? Teardown included of course. Forum HERE

Dave shows how to search for cheap 6.5 digit bench multimeters on Ebay and other auction locations Would you believe less than $200? Equipnet auction The multimeter spreadsheet Forum HERE

Repairing the Schaffner NSD200E Mains Interference Simulator. And the dangers of bad mains filters capacitors, and RIFA brand in particular. HVP-70 High voltage differential probe Forum HERE

A look inside a Swiss made Schaffner NSG200E Mains Interference Simulator after it released the magic smoke. A very unusual bit of kit that tests products for mains line interference like lightning strikes, transients, and dropouts. May involve alien crop circles. Forum HERE