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Monday, March 18, 2013

Did You Check the Switch???

Did you notice, the Kind of Cool Looking Pic?... It has an Accidental Reflection of me, in the Shiny PC Start Button Panel...

I replaced the Power Switch on my Mom's Computer Case. It's a PowerUp ATX Black Mid-Tower Case - Clear Side, 2x USB, Audio Ports, 4x 5.25" Bays, 6x 3.5" Bays, 450-Watt Power Supply MPN: TC3J-4050 P. It was sticking, in the On Position. It is a "Momentary Switch". So, this caused the Computer to Shut Down. Just a few seconds after Trying to Boot Up the Computer. This was an intermittent problem. So, it took me a while to figure it out. I finally realized, that every time you turned on the Power Switch on the Power Supply (PSU). It would always, Eminently Try to Boot Up. Or it started doing this after a few weeks of trying to figure out what was wrong with this thing. When it worked. It worked perfectly and ran just like it should. But, it finally got to where it wouldn't Boot Up at all. I finally borrowed a Multimeter, that has a Beep on Continuity feature. So, it was easier to test the switch. Actually, I don't remember testing the Switch, by it's self, before this. On the first Test. The Switch was always on. Then I tested it again, after a few dozen Presses and it worked like it should. I decided it was ok. But, as a Precaution. I Hooked up a Working Switch from another Computer to the Motherboard to make Sure. Boy, I'm glad I did! The Computer Booted up perfectly on the Replacement Switch! I knew that Processor wasn't Bad! But, it was the only thing that I hadn't Removed and Replaced so far... I had just Put in a Brand New Motherboard, you see. An AS Rock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS FX. That's what I had decided was wrong with it. I had decided that the original Motherboard. A Biostar MCP6PB M2+ Motherboard - Socket AM2+, µATX, Audio, GeForce 6150 Graphics, SATA, RAID. MPN: MCP6PB M2+. Had stopped working, because of a Bios Bug. That BioStar has an update for on the Biostar We b Site. What's that old saying? About Occam's Razor?... Well, I thought that the Bios Bug was the Most Likely Problem. But, in this case... I was wrong!:O But, I'm very Glad that I figured this one out! Why, do these things only happen to Mom's Stuff??? When it makes me really look bad:O... I mean, I really do know what I'm doing with these things, Mom. At least when your not waiting for me to fix yours and wondering why it's taking so long... First I checked the Memory. I put in a known Working Memory Module. Then the Power Supply. I checked the voltage on all of the wires. I even put the Power Supply in another System to see if it was putting out enough Amps to Run a working System. Later, a couple of weeks later. I even put an identical Power Supply (PSU) from one of my Computers in this Box. To maker darn sure, that it was not the Power Supply. I tool the Video Card out and put it back in. I don't know how many times. I Unplugged all of the lights. The Case Fan. I tried it all! But, I saved the Best for Last... The Switch... Now, to put that BioStar Motherboard, Back in there and see if it really is still working... And Yes it is, working just as is should. Now, on to installing that Bios Update (Trying Again). If your running Linux, like me and Can't run the Windows Bios Update Utility... Would it really hurt them to Support Linux too? And NO, it won't work in Wine (the Windows Emulator) either. Believe me, I've tried. Several times and used every trick that I know! The Biostar MCP6PB M2+ Motherboard wont update the Bios from a USB Stick, like the Biostar Web Site Says (PDF) Says, either. "3. Insert the USB pen drive that contains the BIOS file to the USB port. 4. Power on or reset the computer and then press Clt;F12; during the POST process." Pressing F-12 during Boot up, Does Nothing. But, I did find a way Built into the Bios. To do an Update from a Floppy Disk. But, who has Floppy Drives, these days? Well, I do... Just not in this Box. I tried 3 different Floppy Drives, that I had on hand and none of mine worked. The Bios Update Utility. Kept saying that it couldn't Read the File. It showed up in the window list. But, no go... So, finally I dragged an old Win98 Machine out of the Garage. Wrote the Bios Update file to the Floppy Disk. Took that Floppy Drive and the Disk out. And Put them in the BioStar System. And then the Darn Computer would Not Boot Up Again! Not even one more time!:( Not until I finally found the Real Problem... The Very Cheaply Made Factory Power Switch. I installed a Brand New Switch, that I already had. I really wanted to put in that "Slightly Used" Switch, that I had. It was one, from a 10 year old PC. Those Computers were made allot better than the one's they Produce Today. I have only seen a couple of those old Switched go bad, in the last 14 years. But, that Switch was going to take some real work and modification to get it to mount in the Case and stick the right distance into Plastic Front Cover. In order to work with the Shiny Silver Button. So, I went with the New Barrel Style Switch, that I had. I just had to Drill out the Square Hole in the Plastic Cover. And Hot Glue it in Place. Like they did with the Original Switch. I think I got my New Switch from Parts Express. Don't remember now, for sure. But, they usually sell better quality stuff. Than what you get in Production Model PC's, these days. So, from now on. The first question I should ask my self, is... Did You Check the Switch???

Don

Don and Mom's PowerUp ATX Black Mid-Tower Case Black with Red and Blue Lights - Biostar MCP6PB PowerUp Barebone Kit: AMD Barebone Kit - Biostar MCP6PB M2+ Mobo, AMD Athlon 64 X2 CPU, Ultra 2GB PC5400 DDR2 RAM, Seagate 7200.12 HD, LG DVD Writer, PowerUp ATX Black Mid-Tower Case w/450W PSU at TigerDirect.com; Biostar MCP6PB PowerUp Barebone Kit - Biostar MCP6PB M2+ Mobo, AMD Phenom X4 9650 CPU, Centon 2GB DDR2 RAM, Hitachi Deskstar 1TB Internal HD, PowerUp Black ATX Mid-Tower Case w/450W PSU at TigerDirect.com

Biostar MCP6PB M2+ Motherboard Socket AM2+ from Mom's AMD Processor: Motherboard Socket AM2+ - Google Search; GIGABYTE - Motherboard - Socket AM2+; AMD Athlon 64 X2 5000+ CPU - 2.20GHz, Socket AM2; Socket AM2+ - Wikipedia, the free encyclopedia; Socket AM2+ Phenom II processors are not compatible with AM3 motherboards. Forced installation can cause damage not covered by AMD warranty; Amazon.com: Motherboard Socket AM2+: Electronics; Results for Motherboard Socket AM2+ - OutletPC.com; Motherboard Socket AM2+ - Google Search; Foxconn M61PMV - motherboard - micro ATX - Socket AM2 / AM2+ - GeForce 6100 - Socket AM2 / AM2+; Motherboard Socket AM2+ - Google Search; Foxconn M61PMV - motherboard - micro ATX - Socket AM2 / AM2+ - GeForce 6100 - Socket AM2 / AM2+; GIGABYTE - Motherboard - Socket AM2; BIOSTAR :: Home; MCP6PB M2+ :: Motherboard :: BIOSTAR; bios_update.pdf (application/pdf Object); bioscreen.pdf (application/pdf Object); Biostar MCP6PB M2+ Motherboard - Google Search; MCP6PB M2+ :: Motherboard :: BIOSTAR; MCP6PB M2+ :: Motherboard :: BIOSTAR; Biostar MCP6PB M2+ Motherboard - Socket AM2+, µATX, Audio, GeForce 6150 Graphics, SATA, RAID at TigerDirect.com; Amazon.com: Biostar MCP6PB M2+ DDR2 AM2+ NVIDIA GeForce 6150 / nforce430a MATX AMD Motherboard: Electronics; OutletPC.com - ASRock N68C-GS FX AM3+ DDR2/DDR3 GeForce 7025 MicroATX Motherboard; Amazon.com: AS Rock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS: Electronics

Biostar MCP6PB M2+ Motherboard Socket AM2+ Mom's won't finish boot: Biostar MCP6PB M2+ Motherboard Socket AM2+ won't finish boot - Google Search; Biostar MCP6P-M2 biostar mcp6p m2+ socket am2+ motherboard; Biostar MCP6P-M2 mcp6pb m2+ manual; Biostar Le display Motherboards Problems & Solutions - Page 2 - FixYa; Biostar MCP6PB M2+ - FixYa; My cpu had been working fine for 5 months after installation. - FixYa; Biostar MCP6P-M2 mcp6p-m2 bios won't boot to ide; Boot Options | Biostar MCP6P3 Support; MCP6PB M2+ :: Motherboard :: BIOSTAR; MCP6PB M2+ :: Motherboard :: BIOSTAR - Downloads and Bios Update; Index of ftp://bishopco.homeip.net/pub/Pics-Biostar-MCP6PB-M2+-Motherboard-Version-6-3-Bios-info/; New RMA Request - BIOSTAR®; RMA Request Submitted - BIOSTAR®; My Account - BIOSTAR®

AS Rock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS

Socket AM2

DonsDeals Amazon Associates Store. Same Great Deals! Clean and Easy to Read Pages. - Search Results - Computers

DonsDeals Amazon Associates Store. Same Great Deals! Clean and Easy to Read Pages. - AS Rock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS

Amazon.com: AS Rock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS: Electronics

RMA Experience ASRock Motherboard N68C-GS - Google Search

ASRock N68C-GS FX AM3+ NVIDIA GeForce 7025 / nForce 630a Micro ATX AMD Motherboard - Newegg.com

RMA ASRock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS - Google Search

Amazon.com: Customer Reviews: AS Rock FX Socket AM3 Plus NVIDIA GeForce 7025 A V GbE Micro ATX Motherboard N68C-GS

ASRock

ASRock N68C-GS FX - Motherboard I bought for Mom

ASRock > N68C-GS FX - Specs

ASRock > N68C-GS FX - Downloads

ASRock > N68C-GS FX - User Manuals

ASRock > N68C-GS FX - FAQ

ASRock > N68C-GS FX - CPU Support List

ASRock > N68C-GS FX - Beta Software and Driver Downloads

Educational Linux Distro provides Tech Bundle for Kids and Educators

This new Educational Linux Distro, called Ubermix, looks interesting (see article below). Although, Educational Linux Distros are not new. Such as the Linux Distro's, Apps and Computer Kits in these links (just to name a few that I had in my Bookmarks)...

Educational Linux Distros, Apps and Computer Kits

Linux Today - The Linux Desktop: Rich with educational software

The Linux Desktop: Rich with educational software

Overview | Adafruit Raspberry Pi Educational Linux Distro | Adafruit Learning System

Occidentalis v0.2 | Adafruit Raspberry Pi Educational Linux Distro | Adafruit Learning System

Linux Today - Educational Linux distro provides tech-bundle for kids and educators

The Linux Desktop: Rich with educational software | ZDNet

SIGs/Education/Spin - FedoraProject

SIGs/Education - FedoraProject

Linux Today - 75 Open Source Replacements for Popular Education Apps

Linux Today - 65 Open Source Apps That Replace Popular Education Software

Mandriva Provides an Educational Solution for Schools and OEMs - Softpedia

DonsDeals: Beginners Guide to The TI MSP-EXP430FR5739 Experimenter Board

Linux Today - The Linux Desktop: Rich with educational software

Raspberry Pi $25 to $35 PC Board Kit for Education and Experimentation

: Raspberry Pi Foundation; YouTube - Raspberry Pi - the £15 computer; Questions remain over $25 Raspberry Pi - TECH.BLORGE.com; The Raspberry Pi Computer Is Finally Being Manufactured ~ Web Upd8: Ubuntu / Linux blog; Raspberry Pi Lands eBay Bidding Up To $2,700 USD; $25 Linux PC 'Raspberry Pi' to Go in Production Early Next Year ~ Ubuntu Vibes; Build the 2006 prototype of Raspberry Pi's $25 PC – Computer Chips & Hardware Technology | Geek.com; Simple 3d graphics on a microcontroller - YouTube; RaspBerry Pi on DonsDeals Blog - Google Custom Search; DonsDeals: XBMC running on Raspberry Pi; DonsDeals: Raspberry Pi's Gertboard expansion board already works (video) – Computer Chips & Hardware Technology | Geek.com; Group: Raspberry Pi - element14; Arch Linux ARM available for download | Raspberry Pi; Register here to express an interest in Raspberry Pi; Raspberry Pi sells out within one hour | Linux User; Raspberry Pi gets Arch Linux | Linux User; FAQs | Raspberry Pi; Group: Raspberry Pi - element14; About us | Raspberry Pi; Farnell / Electronic Component Distributors / Suppliers / Electronics, Electrical Parts, Electrical Components and Wholesale Electronics.; RS Components | Electronic and Electrical Components; Export | Electronic Components | Electronic Parts; Register interest for your @Raspberry_Pi.; Raspberry Pi | A revolution in low cost computing. Brought to you by Orbits IT; Raspberry Pi - Wikipedia, the free encyclopedia; RASPBRRY-PCBA - RASPBERRY-PI - RASPBERRY PI MODEL B - BOARD ONLY | Newark; PCH Search & Win: Raspberry Pi; Don't bring this teacher an apple, he prefers Raspberry Pi | opensource.com; Overview | Adafruit Raspberry Pi Educational Linux Distro | Adafruit Learning System; Occidentalis v0.2 | Adafruit Raspberry Pi Educational Linux Distro | Adafruit Learning System; DonsDeals: Raspberry Pi - Seneca Fedora Remix 14 Release

This one called Ubermix, may be good for those Teachers and Kids who like a Mobile Phone GUI Interface...

Don

Educational Linux distro provides tech-bundle for kids and educators

Interview with Jim Klein, founder of Ubermix - opensource.com

Posted 13 Mar 2013 by Jason Hibbets (Red Hat)

Image by opensource.com

How are we going to teach the next generation about open source and Linux? More importantly, how can we get the right technology into classrooms to empower our educators to teach our children the open source way?

The opportunities that open source presents to education and academics is growing each day. Opensource.com highlights individual tools like Scratch and TuxPaint that are starting to make an impact—but, what about an entire education distribution? How do we make it easier to get an entire toolset into the hands of school systems, teachers, and students? How can we really move the needle and present a revolutionary open source operating system designed for kids and education?

Enter Ubermix.

Ubermix is a Linux distribution built by educators, for educators, and for students, "with an eye towards student and teacher empowerment." That's why the "desktop" looks like a mobile phone. And it comes pre-installed with tons of open source applications that are geared toward education and creativity.

We caught up with the founder of Ubermix, Jim Klein, to find out more about this Linux-based operating system and how the project aims to create a turn-key installation process, reducing the complexity and deployment often associated with installing a Linux distro. We also wanted to hear some of the stories from the people already finding success with Ubermix.

Takeaway sneak peek: You can make a difference for the next generation. Just tell someone you know in education about Ubermix.

Tell our readers about Ubermix and your target audience.

Ubermix is designed to bring the power and flexibility of free software and an open operating system to kids and the education community. While there are a number of general purpose Linux builds out there, few have made significant inroads into schools, due in large part to their complexity and general purpose design language. What Ubermix brings is an easy entry point and sensible design decisions, having been assembled with a real understanding of the challenges education technologists face when attempting to implement something new. Features such as a five minute install from a USB key, extraordinary hardware compatibility, and a quick, 20-second reset process make it possible for understaffed and underfunded school technology teams to scale up significant technology access without increasing the need for technical support.

For kids, Ubermix brings a far more approachable interface to Linux, virtually eliminating the traditional "desktop" paradigms in favor of something similar to a cell phone that's far easier to use. Couple that with more than 50 carefully selected applications across a broad array of subject areas and that quick reset function, which enables a student to solve their own problems without losing any of their work, and you have a powerful tool for learning.

What are some of the open source applications included with Ubermix?

Ubermix comes pre-loaded with a number of applications for education, productivity, design, programming, Internet, and multimedia construction. Education oriented applications like Celestia, Stellarium, Scratch, VirtualLab Microscope, Geogebra, iGNUit, and Klavaro, as well as educational games like TuxMath, TuxTyping, gMult, and Numpty Physics all bring with them plenty of opportunities to learn.

Internet applications we all know and love, like Firefox, Thunderbird, Chrome, Google Earth, and Skype are all there. Common productivity apps like LibreOffice, NitroTasks, Planner Project Management, VYM (View Your Mind), and Zim Desktop Wiki are too. Kids interested in design will find the GIMP, Inkscape, Scribus, Dia, Agave, and even TuxPaint for the younger ones. And apps like Audacity, Openshot, Pencil, and ffDiaporama help round out the media offerings. These, and many more, make Ubermix a powerful launchpad for student creativity and learning.

What does the future hold for Ubermix?

I'm constantly amazed and humbled by the growth of Ubermix, and continue to work towards making it better, easier, and more powerful for kids, teachers, and technologists. I think touch will certainly play a role in the future, as will alternative devices and form factors. It will be interesting to see just how the recent hardware renaissance plays out, and where Ubermix fits into the future needs of schools. I also plan to work with the community to build some sort of a web-based management interface that would make larger deployments even easier to manage.

What is the most interesting way Ubermix has been used so far?

People always find ways to do amazing things with Ubermix. A team of middle-school students have built a number of computer labs in the central valley using government surplus machines. Kramden Institute is planning to deploy Ubermix on 3000 computers given to needy kids to help bridge the digital divide.

A retired education technology leader is not only building and donating Ubermix machines to needy families, but is also touring the country, sharing Ubermix at conferences in several states. And I once heard from an activist who shared with me that he was giving Ubermix netbooks to kids in Central America. It's truly amazing and inspiring.

Where does someone get started with Ubermix and how can someone get involved?

You can find all things Ubermix at ubermix.org. As with any open source project, the bigger the community the better! New ideas and code are always welcome, as are translators, writers for the wiki, and anyone willing to help out answering questions in the forums. And, of course, help spreading the word!

Bonus: What's the best "feel good" story from the Ubermix community?

The best thing about Ubermix is seeing an empowered student do something amazing with it and then share how they did it, both within their classroom and school, and the online world. From that geeky kid who struggled with relationships until his peers found out what he could do with a computer... to the special day class kids who get to shine as they teach the regular ed kids how to build something... to the teams of fourth graders writing apps and deconstructing code... to the creative, outgoing kid who makes and makes and makes things that he shares online. It's always incredible to behold.

It's the power of community driven by open source, writ large for the world to see.

Tags:

6 Comments

Alan B on 14 Mar 2013

Want to get kids to use it? Make it run MineCraft. They'll be less interested in an array of applications of which a fair few look worse than Windows shareware from 1998.

Topher Hunt on 14 Mar 2013

"Finally, a version of linux designed for kids": I'm confused about this article's position towards the longstanding educational distro Edubuntu. Are you aware of it? Would you consider it not fit for students and educators? The wording here acts as though Linux has never produced an education-oriented bundle, and that doesn't seem accurate.

And, agreed about Minecraft. That seems like an obvious one to include for kids... although currently, Minecraft is only free for the Raspberry Pi platform.

cabalist on 14 Mar 2013

Yeah, Edubuntu has been around for a long time.

My daughter's PC runs Edubuntu 11.10 and it comes with A LOT of educational software already installed. It also changes some (maybe a lot) of settings to make it more accessible and friendly to kids.

Not to mention the awesome software (oh wait, I already did) like Scratch, Celestia, and the primary, secondary, and tertiary educational bundles!

Good stuff.

But I am always glad to see MORE opportunites to expose kids to open source software and linux.

William on 14 Mar 2013

Edubuntu seems to be made for younger kids. Kids tired of it very quickly since those programs were mostly made for 3-6 year olds. Ubermix seems to offer programs for slightly older kids. By the time they're 10, they'll mostly be outgrowing ubermix as well. By 11-13, they better have learned how to touch type already and should be working beyond scratch. Some of them should already be learning python or Java.

Richard on 14 Mar 2013

Minecraft does already run on linux. So does Steam (on Ubuntu) which is a gaming platform. But you need to be sure there is good support for your graphics card otherwise you may not get great results.
I think that a list of needed apps be placed on the site - you may get interest from a lot of programmers looking for a hoby project or recognition or even an avenue to get new apps for the Ubuntu on phones which will be compatible.

picpichopefullsoul on 18 Mar 2013

Ubermix is a much improved desktop using the base provided by unity 2D. But it has a big flaw: no iso image is provided, not allowing for an easy installation in more machines than the one it targets

Go there...
http://opensource.com/education/13/3/ubermix-linux

Ubermix is an all-free, specially built, Linux-based operating system designed from the ground up with the needs of education in mind

: Interview with Jim Klein, founder of Ubermix | opensource.com; Kids learn to program by making cool games | opensource.com; Open source creative tools like TuxPaint loved by many at the library | opensource.com; About the ubermix; ubermix Home; ubermix Download & Install; ubermix Download Files; ubermix Basics; ubermix Customization; ubermix Blog; ubermix Wiki; ubermix Forums - Index

Saturday, March 16, 2013

Capacitors - Testing Caps Building an ESR Meter

This would be a great tool to build for your Electronics Projects...

Don

Testing caps with a DIY ESR meter

Building an ESR Meter

Building a simple ESR meter for troubleshooting electrolytic capacitors.

What is ESR

"Never in the history of mankind, have so many boards been ruined by so few components"

Winston Churchill (or someone like him) - on Electrolytic Capacitors

Electrolytic Capacitors are a very common cause of failure in electronics equipment. Over time, electrolytic capacitors tend to dry-out and fail. Often the failure can be found by simple visual inspection (an exploded or deformed capacitor is hard to miss). In other cases however, the failure is more subtle and manifests itself by an increase of the capacitor's Equivalent Series Resistance (ESR). An ideal capacitor of course, has zero equivalent series resistance. In reality, a multitude of non-ideal characteristics can be modeled as a simple series resistor. Manufacturers often specify ESR at a fairly high frequency of 100 KHz and it is typically a very low value, depending of course on the capacitance value and voltage rating. Typically, the higher the capacitance, the lower the ESR. Large capacitors tend to be used for power supply filtering where even small values of ESR translate in increased internal power dissipation and premature capacitor failure. If you repair electronics equipment, an ESR meter is an essential item in your toolbox. Of course you can buy already made units (See this one from Amazon.com for example) but building one yourself is relatively simple and rewarding. In this article, I'll show you how I built one using common components in my hobbyist Electronics Lab.

Measuring ESR

An ESR meter is in effect an AC Ohm-meter designed to detect very low value resistors. This can be achieved by applying a fairly high frequency AC signal to the capacitor (100 KHz in this design) and measuring the effects of the resistive drop across the capacitor. At 100 KHz, the reactive component of the capacitor (Xc = 1/(2*pi*f*C) ) is negligible for most common electrolytic capacitor values. The circuit shown in Figure 1 uses this operation principle. A simple 555 timer generates a square wave at about 100 KHz. The 2:1 step-down transformer reduces the effective source impedance of the 555 output driver and couples the signal to the capacitor under test and the two 12 Ohm resistors. The 1N4007 diodes protect against capacitors that might still be charged (in this case, the diodes will effectively "discharge" them to about 0.6V). The resulting signal at point (1) is about 200 mV pk-pk. This voltage is small enough that the tester can sometimes be used in-circuit without forward-biasing any PN junctions. Note however that often several capacitors are connected in parallel in real-world designs so the measurement might be misleading. A 2N3904 transistor amplifies the signal coupled through the capacitor with a gain of about 10. This signal is the rectified, filtered and applied to a simple analog voltmeter. Note that because of the way the capacitor is connected, the voltage will be maximum for a 0 ESR capacitor and minimum for a large ESR capacitor. Therefore, the meter is adjusted by first shorting the test leads and ensuring the meter deflects till the end. This is done by adjusting the series 10K Ohm pot. The scale is very non-linear so you might want to test with know resistor values and mark the corresponding numbers in the scale. I didn't do this in my design but instead kept a separate table that I later glued on the ESR box.

Figure 1 - ESR Meter Circuit

The circuit is powered from a single 9V battery. To maximize battery life as the voltage drops over time, I decided to use a low-cost LDO instead of a more common 78L05 regulator. The LM2936 is relatively inexpensive and will ensure operation even when the battery approaches 5.5V. Though not shown in Figure 1, I later also added an LED ON/OFF indicator after the switch.

Operation

To better illustrate how the circuit works, let's have a look at the waveforms at points (1), (2) and (3) marked in Figure 1 with a shorted lead (ESR = 0) and with a relatively high ESR = 5.6 Ohm. The waveforms (1), (2) and (3) in Figure 1 correspond to Channels 1, 2 and 3 Figure 2's oscilloscope shot. Figure 2 shows that the signal at the output of the capacitor/resistor divider is only about 232 mV pk-pk and that the transistor effectively multiplies that value by a factor of over 10. Channel 3 is the already rectified and filtered signal, in this case about 1.35 V.

Figure 2 - Waveforms with shorted test leads (ESR = 0)

Figure 3 shows the meter I used in full-depletion for this situation (after adjusting the 10K potentiometer).

Figure 3 - Full depletion (ESR = 0)

When a high ESR capacitor (in this case 5.6 Ohm) is inserted across the test leads, the output voltage at point (2) decreases and so does the resulting DC level at point (3) as depicted in Figures 4 (oscilloscope) and Figure 5 (meter).

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