EEVblog

By David L. JonesTechnology Education

EEVblog episodes

February 06, 2025 EEVblog 1664 – REPAIR with Junk Bin Parts! Keithley 2302
Repair of a Keithley 2302 battery simulator with junk bin parts. But it did put up a fight!
Teardown video: https://www.youtube.com/watch?v=5LK8wduZsy0
Forum: https://www.eevblog.com/forum/blog/eevblog-1664-repair-with-junk-bin-parts!-keithley-2302/
00:00 – Faulty VFD display in a Keithley 2302 Battery Simulator
01:22 – Teardown
03:14 – The Display driver PCB
04:30 – Solder Sucking Sucks
05:26 – The VFD display module, a Newhaven Display VFM162SDAR8
06:50 – Probing Pro Tip
07:28 – Probing the VFD signals on the oscilloscope
09:42 – Searching for a replacement 16×2 VFD display
15:03 – Potential replacement LCD
16:38 – Identical replacement found
17:44 – Lets check the junk bin…
18:33 – Pinout trap for young players
19:25 – First test FAIL, but hold on a second, lets try something…
21:09 – Winner Winner Chicken Dinner
22:12 – WOAH, now it’s not working?
24:09 – Lets try THIS…
27 min
January 24, 2025 EEVblog 1663 – BM786 Multimeter REPAIR + InEr Error Investigation
Repairing a customers Brymen BM786 multimeter, and investigating the cause of the InEr error message on the input jack alert feature.
Plus a giveaway to a local youngster.
00:00 – A returned BM786 Multimeter with InEr error message
03:23 – Split jacks and input alert circuit
05:19 – In-Circuit probing TIP and Low Ohms mode.
07:19 – A clue?
08:05 – A need a new desoldering gun. Removing the input jacks
10:30 – Bodge testing of the input detection threshold
12:38 – Not one but TWO failed Megger Insulation meters!
13:50 – Megger testing the connectors at 500V
15:19 – Testing a 2nd failed InEr error meter
17:00 – Cleaning the input jacks
19:11 – Heating up the input jacks
20:18 – Getting desperate, removing the input jacks
21:49 – Getting really desparate, removing the input resistors
22:38 – Reassembling the original repaired unit
24:26 – Repaired BM786 GIVEAWAY
Keysight OLED meter repair: https://www.youtube.com/watch?v=CKdeqqo2diI
Forum: https://www.eevblog.com/forum/blog/eevblog-1663-bm786-multimeter-repair-iner-error-investigation/
27 min
January 24, 2025 EEVblog 1662 – Vintage Tandy 200 Portable Computer Claytons Repair/Teardown
This was going to be a repair of a vintage Tandy 200 Portable Computer…
Forum: https://www.eevblog.com/forum/blog/eevblog-1662-vintage-tandy-200-portable-computer-claytons-repairteardown/
00:00 – I sear this Tandy 200 had a problem…
02:54 – Teardown
03:57 – The new BM2257 Multimeter
05:25 – I think it’s the buzzer
08:06 – Microscope teardown
16:20 – They don’t make service manuals like they used to
25:57 – Try to reproduce the fault
32 min
January 11, 2025 EEVblog 1661 – AC Basics Tutorial Part 5: Time Domain vs Frequency Domain
The difference between Time Domain and Frequency Domain in AC circuit analysis.
AC Theory Playlist: https://www.youtube.com/playlist?list=PLvOlSehNtuHvD6M_7WeN071OVsZFE0_q-
Forum: https://www.eevblog.com/forum/blog/eevblog-1661-ac-basics-tutorial-part-5-time-domain-vs-frequency-domain/
13 min
January 05, 2025 EEVblog 1660 – AC Basics Tutorial Part 4: Resistors, Capacitors, Inductors
Part 4 in the AC basics tutorial series. AC applied to resistors, capacitors and inductors, along with Capacitive Reactance and Inductive reactance.
AC Theory Playlist
18 min
January 03, 2025 EEVblog 1659 – Quick 861 Pro Hot Air Station REVIEW
Review of the new Quick 861 Pro hot air station compared to the original 861DW.
Forum: https://www.eevblog.com/forum/blog/eevblog-1659-quick-861-pro-hot-air-station-review/
32 min
December 28, 2024 EEVblog 1658 – TUTORIAL: Mean vs Median
It’s important to understand the difference between Mean and Median, not just for engineering, but for everyday life, so you don’t get manipulated by people with bad intentions.
UBS Global Wealth Report:
https://www.ubs.com/content/dam/assets/wm/global/insights/doc/global-wealth-report.pdf
Forum: https://www.eevblog.com/forum/blog/eevblog-1658-tutorial-mean-vs-median/
17 min
December 20, 2024 EEVblog 1657 – DUMPSTER Samsung 75″ QLED One Connect TV
Almost 30 minutes of tearing down a Samsung 75″ QLED One Connect dumpster TV and trying to power it up to see if it’s busted or not. QA75Q7FNA
00:00 Dumpster Samsung QLED 75″
04:46 – Teardown wasn’t easy as expected…
08:11 – What is this cable retention BS?
11:26 – I’m still at it…
14:22 – Where’s Wally? Follow the voltage.
17:26 – Where do I get 350V DC at a few hundred watts?
21:21 – DIY 350V DC power supply
22:52 – 350V DC right up the clacker
24:19 – I need MORE voltage
Forum: https://www.eevblog.com/forum/blog/eevblog-1657-dumpster-samsung-75-inch-qled-one-connect-tv/
Elecami Wolf videos:
https://www.youtube.com/watch?v=NF-MVDc1K9Y
https://www.youtube.com/watch?v=w_39JC2Dkdc
Trolley Riding videos:
https://www.youtube.com/watch?v=g3A1XNfDxe0
https://www.youtube.com/watch?v=MC_xeEKd5t4
https://www.youtube.com/watch?v=H9erf8rt54s
27 min
December 18, 2024 EEVblog 1656 – MAILBAG: ElectroPermanent Magnet, DIN PSU’s, Sponge, Beelink EQ14 N150 PC
More Mailbag!
00:00 – DPS Ultrathin DIN 5V PSU’s
https://digitalpowersystems.eu/de/standard-produkte/
01:15 – The Knife
06:16 – USB-C Isolator
https://digitalpowersystems.eu/de/schnelle-und-sichere-usb-zu-uart-kommunikation-dank-digitaler-isolierung-und-esd-schutz-fur-ein-und-ausgange/
07:34 – Zubax FluxGrip FG40 Electropermanent Magnet for Drones
https://zubax.com/products/magnets/fluxgrip/fg40
11:55 – Testing the magnet
14:04 – Drone delivered multimeters?
14:53 – Why did someone send this?
15:46 – Wireless Freakin’ Road Charging
https://www.youtube.com/watch?v=sisD61ohzK0
19:37 – Sponge Bonanza
21:21 – Beelink EQ14 Intel Twin Lake N150 Mini PC
Forum: https://www.eevblog.com/forum/blog/eevblog-1656-mailbag-electropermanent-magnet-din-psus-sponge-beelink-eq14/
29 min
December 09, 2024 EEVblog 1655 – How to Discharge Capacitors SAFELY using a Multimeter
You can use almost any decent modern multimeter to safely discharge high voltage capacitor banks WITHOUT a LowZ function.
Forum: https://www.eevblog.com/forum/blog/eevblog-1655-multimeter-tip-discharge-capacitors-using-any-meter/
Transistor Zener Clamp video: https://www.youtube.com/watch?v=BGcKjy_UNQ4
10 min