EEVblog on Odysee

Dave answers an exam question on OpAmps that's interestingly tricky. Bonus opamp tutorial on biasing.
Part 2: https://www.youtube.com/watch?v=33rS0oLULqw

https://www.eevblog.com/forum/beginners/how-to-analyze-the-opamp-circuit/

OpAmp playlist: https://www.youtube.com/playlist?list=PLvOlSehNtuHu2FviAaZaiyXwN41G4b1Lf

00:00 - A tricky exam question
01:45 - What's missing?
03:11 - The two most important Opamp rules
04:44 - THINK about what sort of exam you are in BEFORE answering the question
07:04 - Capacitive reactance "AC resistance"
08:53 - They want you to use frequency, but also IGNORE it? How does that work?
10:21 - When it doubt, assume a short circuit
10:59 - Solving the first part of the question
12:20 - The 2nd rule of AC circuit analysis
13:33 - Solving the second part of the question, what is the AC gain?
15:29 - There is no need to muck around, move on to the next question
15:58 - Let's talk about Opamp Biasing
22:59 - Single pole high pass filter
23:31 - Ripple removal filter
26:24 - Conclusion, why is this question is clever?

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#ElectronicsCreators #OpAmp
...
https://www.youtube.com/watch?v=nDEGqme5Z4g

Teardown and reverse engineering of the new Rigol RSA800 series Real Time Spectrum Analyser, from 4.5GHz to 13GHz.
4.5GHz RSA804
8.5GHz RSA808
14GHz RSA814
https://www.rigolna.com/products/spectrum-analyzers/rsa800/

00:00 - Rigol's new RSA800 Real Time Spectrum Analyser
06:48 - Teardown
11:42 - RF front end box teardown. Mad Man Muntz
14:55 - Back side of the RF block
16:50 - Reverse Engineering with DaveCAD
22:05 - Attenuator & Preamplifier
23:41 - Interesting split into separate HF and LF mixers
25:47 - Preselect filters
27:33 - Flux residue!
28:23 - HF and LF Mixers and 1st stage PLL
30:58 - Downconversion mixing explained
32:48 - 2nd Stage Active IF Mixer, now we are getting serious
36:01 - Final 3rd stage active mixer
36:57 - Dave is WRONG, but why you might want two ADC's vs one
39:20 - No Dave, it's a DAC
40:25 - Speculating on the custom ADC used, and digital quadrature sampling
41:49 - Mystery LTC part, and what on earth is going on here with these PCB couplers?
44:32 - Teardown Conclusion
45:51 - Demo comparison of a DSA815 and RSA808, Real Time vs Swept Analysis

Forum: https://www.eevblog.com/forum/testgear/new-rigol-rsa800-spectrum-analyser/

Datasheets:
SIS378 Switch: https://www.sicoresemi.com/ueditor/php/upload/file/20250818/1755497980219246.pdf
SIAT116 Attenuator: https://www.sicoresemi.com/ueditor/php/upload/file/20260427/1777277733715489.pdf
LF Mixer : https://www.sicoresemi.com/ueditor/php/upload/file/20250923/1758612877124723.pdf
SIM445 HF Mixer: https://www.sicoresemi.com/ueditor/php/upload/file/20260709/1783577453983448.pdf
SIA070 Amplifier: https://www.sicoresemi.com/ueditor/php/upload/file/20260509/1778310579506957.pdf
SIS119 Absorptive Switch: https://www.sicoresemi.com/ueditor/php/upload/file/20250324/1742806808125089.pdf
SIP052 Phase Converter: https://www.sicoresemi.com/ueditor/php/upload/file/20240627/1719477861130248.pdf
SIA332 Amplifier: https://www.sicoresemi.com/ueditor/php/upload/file/20240924/1727159790115927.pdf
LMX2820 PLL: https://www.ti.com/lit/ds/symlink/lmx2820.pdf
LTC5577 Active Mixer: https://www.analog.com/media/en/technical-documentation/data-sheets/5577f.pdf

Web Site: http://www.eevblog.com
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#ElectronicsCreators #Rigol #spectrumanalyzer
...
https://www.youtube.com/watch?v=oci89u-sL0s

Can you repair a PSU by REMOVING a component? Well, in this case, yeah, kinda.
Not recommended for new designs, but it works because the design margins allowed it.

00:00 - My NerdQaxe++ Bitcoin miner has failed. Guru Meditation!
02:13 - Bitmain 1370 chipset thermal paste
03:54 - The flipchip die under the microscope
04:48 - Thermal paste application triggering
06:55 - Time for a new strategy R2. The Vreg temp sensor is now the suspect
07:53 - A look at the open source hardware schematic in KiCAD
https://github.com/shufps/qaxe
09:42 - The TPS53647 4 Phase ASIC Buck PSU controller
https://www.ti.com/lit/ds/symlink/tps53647.pdf
10:23 - The CSD95472Q5MC Synchronous Buck NexFET Smart Power Stage
https://www.ti.com/lit/ds/symlink/csd95472q5mc.pdf
11:50 - We can try wacking a heatsink on + Jaycar field trip
12:41 - Did that fix it?
14:10 - It's becoming obvious what the fault is now
16:24 - Thermal camera testing
16:56 - Oscilloscope time on the 3 phase PSU
18:21 - Desoldering time, maybe
19:42 - Will removing this component work?
23:52 - AutoBalance multi-phase buck conversion for the win

Forum: https://www.eevblog.com/forum/blog/eevblog-1769-repair-by-removing-a-component/

Web Site: http://www.eevblog.com
Hardware Store: https://eevblog.store/
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EEVdiscover: https://www.youtube.com/eevdiscover

#ElectronicsCreators #Repair
...
https://www.youtube.com/watch?v=lcsXd_0qCuo

The CORRECT Way to Compare Battery Bank Capacity. Input referred vs output referred battery capacity explained. And Watt Hours vs Milliamp Hours


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#ElectronicsCreators #Shorts
...
https://www.youtube.com/watch?v=2-wgZjUjqUw

More Mailbag!

00:00 - Dave & Dylan open random Mailbag
03:49 - DIY bodged laser engraver
04:14 - MPPT Solar charge controller
04:56 - Mixed bags
06:01 - DLP Projector Mirror Arrays
08:05 - TDA2030A Power Amp
08:39 - Analog/Digital combo watch
12:23 - Solar Panels
13:52 - Engineering Spelling + 34401A VFD Replacement
https://hubequip.net/products/hp-agilent-34401a-vfd-to-led-display-replacement-led-conversion
17:58 - Treedix USB Cable Tester
https://treedix.com/
24:33 - Zoyi ZT-XC1 Combo LCR & Multimeter
https://zotektools.com/?list_22/137.html

Forum: https://www.eevblog.com/forum/blog/eevblog-1768-mailbag/

Web Site: http://www.eevblog.com
Hardware Store: https://eevblog.store/
Merch Store: https://eevblog.dashery.com/

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#ElectronicsCreators #mailbag
...
https://www.youtube.com/watch?v=B30W9j2LsIY

Teardown and detailed analysis of the Harogic PXN-90 9GHz Spectrum Analyser.
https://www.harogic.com/product/harogic-px-series-standard-spectrum-analyzer-receiver/

Forum: https://www.eevblog.com/forum/blog/eevblog-1767-harogic-pxn-90-9ghz-spectrum-analyser-teardown/

Web Site: http://www.eevblog.com
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#ElectronicsCreators #Harogic
...
https://www.youtube.com/watch?v=tyB31vEj43c

Youtube have just completely changed what constitutes a "view" !
https://support.google.com/youtube/thread/433409976

Web Site: http://www.eevblog.com
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#ElectronicsCreators #youtube
...
https://www.youtube.com/watch?v=PuQbaWpShHI

All the EEVblog videos are now available on Spotify thanks to Dylan vibe coding a bulk upload engine with Claude AI. No API? No problem!
https://open.spotify.com/show/2LsuS1kDu8jbE3GsOxDQrk



Web Site: http://www.eevblog.com
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If you find my videos useful you may consider supporting the EEVblog on Patreon: http://www.patreon.com/eevblog

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#ElectronicsCreators #Spotify #Claude
...
https://www.youtube.com/watch?v=nNTaLhJzw14

Dave's Rod PodMic USB failed, so might as well do a quick teardown before returning it under warranty.

Failure sound test video: https://www.youtube.com/watch?v=fUll85g8weE

Forum: https://www.eevblog.com/forum/blog/rode-podmic-usbs-are-failing!/

Web Site: http://www.eevblog.com
Hardware Store: https://eevblog.store/
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EEVdiscover: https://www.youtube.com/eevdiscover

#ElectronicsCreators #Rode #Microphone
...
https://www.youtube.com/watch?v=OrWwzY8DNb8

Using an Waveshare ESP32 RS485 module on the Brink Flair 400 home air ventilation system to email alert if the inlet pressure goes about 400 pascals. And using Claude AI to generate the Arduino code required.

00:00 - Brink Flair 400 ventilation system
02:04 - Waveshare ESP32-S3-RS485-CAN module
06:32 - Using Claude to generate Arduino code
17:04 - Pirate Mode Activated
24:21 - Installation and testing


Web Site: http://www.eevblog.com
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#ElectronicsCreators #project #ESP32
...
https://www.youtube.com/watch?v=kHu2xe9iCIc