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most recent messages 5/22/2013 10:57:25 AM Glen Chenier >(a) slow power up & fast power up and bouncy power upRan into a batch of voltage-controlled crystal oscillators that failed production test when the cards were hot-inserted into a live backplane. ... blog roll message boards chat Phase Noise Analyzers Take Over From Scopes Michael Dunn, Editor in Chief, Scope Junction, 5/22/2013 Comment now Phase noise analyzers have traditionally been RF tools, but they're seeing more use in other areas when scopes and spectrum analyzers run out of steam. Notching the Frequency Response? Just Listen Michael Dunn, Editor in Chief, Scope Junction, 5/21/2013 Comment now 17 comments I recently came across an article by Rich Pell on EE Times discussing headphone equalization (EQ). Pell describes inserting a couple of notches to compensate for ear-canal resonances. I had to check this out. Most recent post, MD, 5/21/2013 7:37:18 PM >it should be a valid method of identifying locations of resonances. Good... How Many Bits Would You Like With That? Michael Dunn, Editor in Chief, Scope Junction, 5/20/2013 Comment now 40 comments Several manufacturers have been publicizing 12-bit scopes lately. How important is higher resolution, and do you need it? Most recent post, MD, 5/21/2013 11:04:03 PM >Before you say 'use AC' mode: that doesnt work. I need to know that this signal... Bouncing Short Beats Clean Short for Real-World Testing Glen Chenier, Engineer, 5/17/2013 Comment now 18 comments Gadgetech's recent blogs on test thoroughness reminded me how some faults are found only because a specific method is followed, along with a bit of luck. This tale also demonstrates the beauty of a four-channel scope that sees almost everything that goes on simultaneously. Most recent post, Glen Chenier, 5/22/2013 10:57:25 AM >(a) slow power up & fast power up and bouncy power upRan into a batch of voltage-controlled... Measuring (Small) Phase Errors With a Scope Ramkumar Ramaswamy, PhD, Chief Scientist, 5/16/2013 Comment now 6 comments Recently I was working on the design of a simple quadrature upconversion module for a Software Defined Radio (SDR) front-end. What it did was fairly straightforward -- take the baseband I and Q outputs from a direct-conversion receiver (an ADRF6850) and feed these to two modulators (the good old MC1496), configured as I and Q modulators, then combine ... Most recent post, bobs bots, 5/21/2013 10:48:06 PM For the quadrature case , dividing A into B is similar to multiplying... Choosing a Cheap Android – Help! Michael Dunn, Editor in Chief, Scope Junction, 5/15/2013 Comment now 48 comments In some previous blogs, we've discussed iOS apps, oscilloscope and other, as well as remotely controlling a scope from a device. Now, I want to get a cheap Android tablet to see what it can do in this arena. But you need to help me pick one. Most recent post, MD, 5/21/2013 7:01:20 PM Just an hour?!? Can You Lend Me an ARM? Michael Dunn, Editor in Chief, Scope Junction, 5/14/2013 Comment now 55 comments I really like microprocessors and microcontrollers, little chips with the only goal in life to do your bidding. And I keep wanting to do one interesting project or another, though never seem get around to it. But I plan to change that. Most recent post, Wale Bakare, 5/21/2013 4:11:10 PM I was referring to language translator phone call app. This particular mobile app... The Direct View Storage Tube Shiv Balakrishnan, DSP & Test Expert, 5/13/2013 Comment now 13 comments Engineers of a certain vintage (I won't say how old except you had to be around in the late 1970s or early 80s) might remember the Tek 4051 desktop computer, or the venerable Tek 4014 graphics display terminal. The graphics came in only one color -- green -- but the quality of the picture was superb, and these terminals were popular in engineering ... Most recent post, afritgo, 5/20/2013 10:23:41 AM >> Afritgo, it's all about how they are marketing the technology. Sure,... Friday Fun: Test Those Tubes Michael Dunn, Editor in Chief, Scope Junction, 5/10/2013 Comment now 52 comments Believe it or not, every Radio Shack -- hell, almost every drugstore -- once had a tube tester sitting at the back, available for all to use. Pulling a bunch of tubes out of a malfunctioning radio or TV, and heading off to test them, was always an exciting little excursion! Most recent post, MD, 5/14/2013 6:53:08 PM > I consider it important for students in any branch of engineering to have... Unbalanced Load Bill Copeland, Senior Electrical Engineer, 5/9/2013 Comment now 57 comments Have you ever looked around your workplace and felt that things were just not quite right? Specifically, I'm thinking here about job responsibilities and projects that you and your co-workers are assigned. Most recent post, Myscope, 5/17/2013 2:43:24 AM "I'm just a contractor to government so no real job security" BC, I think such... Inspecting the Wind Turbine Michael Dunn, Editor in Chief, Scope Junction, 5/8/2013 Comment now 28 comments We've all had the experience I'm sure. Someone tells us about a project we are to undertake, but the details get lost in translation. There's no substitute for hands-on, eyes-on inspection of the situation. Most recent post, William K., 5/20/2013 10:04:08 PM Right now, today, and for the past few years, there have been those offering the... Next 5 blogs + All blogs All blogs most commented 48 Choosing a Cheap Android – Help! Michael Dunn, Editor in Chief, Scope Junction, 5/15/2013 40 How Many Bits Would You Like With That? Michael Dunn, Editor in Chief, Scope Junction, 5/20/2013 18 Bouncing Short Beats Clean Short for Real-World Testing Glen Chenier, Engineer, 5/17/2013 17 Notching the Frequency Response? Just Listen Michael Dunn, Editor in Chief, Scope Junction, 5/21/2013 6 Measuring (Small) Phase Errors With a Scope Ramkumar Ramaswamy, PhD, Chief Scientist, 5/16/2013 blog roll message boards chat 5/22/2013 10:57:25 AM Re: Dodecahedron Testing: >(a) slow power up & fast power up and bouncy power upRan into a batch of voltage-controlled crystal oscillators that failed production test when the cards were hot-inserted into a live backplane. They oscillated at the wrong frequency,... Glen Chenier on Bouncing Short Beats Clean Short for Real-World Testing 5/22/2013 12:26:20 AM Re: Silence: Yep had problem with 3 paralled 28V supplies once, 3 green lights doesn't mean 3 good supplies! The power unit failed to hold the load, and we found two faulty power modules, I guess one must have failed silently months ago.&nbs... bobs bots on Bouncing Short Beats Clean Short for Real-World Testing 5/21/2013 11:04:03 PM Re: Its not the bits that count. Its the dynamic range !: >Before you say 'use AC' mode: that doesnt work. I need to know that this signal goes from 19.95 to 20.05 volt ! Could be time to combine AC mode with a DMM??? :-) MD on How Many Bits Would You Like With That? 5/21/2013 11:01:15 PM Re: 8 vs 12 bits: >(or maybe it's my $50 probes?) Hmm, maybe. Would artificial peaking give a true representation of rise time? I don't think it would, though yeah, it would definitely speed it up ;-) MD on How Many Bits Would You Like With That? 5/21/2013 10:58:34 PM Re: Its not the bits that count. Its the dynamic range !: >Worked a treat! Still got one somewhere.... A battery? Cool. MD on How Many Bits Would You Like With That? 5/21/2013 10:57:40 PM Re: Its not the bits that count. Its the dynamic range !: >give completely wrong values as they calculated based on pixels on the screen, they dont calculate based on raw samples. I think most scopes do calcualte on raw values. It's just that their ADC range is barely larger than the screen (which... MD on How Many Bits Would You Like With That? 5/21/2013 10:56:31 PM Re: Its not the bits that count. Its the dynamic range !: Hmm , in the old days we used a battery with ten turn pot to offset big voltages. Worked a treat! Still got one somewhere.... bobs bots on How Many Bits Would You Like With That? 5/21/2013 10:54:34 PM Re: 8 vs 12 bits: And what about the little trim cap in the probe? You can change the amplitude (and shape) of high frequency square waves +/- 5% by fiddling with this. I've also found the trim cap setting to produce the fastest rise times can be different... bobs bots on How Many Bits Would You Like With That? 5/21/2013 10:54:31 PM Re: Its not the bits that count. Its the dynamic range !: >Most scopes cannot apply enough dc offset to their input stages to compensate for this. True enough, though my 1960s 1A5 plugin looks like it could do it :-) MD on How Many Bits Would You Like With That? 5/21/2013 10:48:06 PM Tangent?: For the quadrature case , dividing A into B is similar to multiplying A by B . (If B is the reference of amplitude 1.0000 units) So when close to quadrature the phase angle described as tangent(A/B) is approximately zero... bobs bots on Measuring (Small) Phase Errors With a Scope 5/21/2013 10:47:34 PM Re: Dodecahedron Testing: >sufficient to make a small current flow in the internal protection diodes (Many ADC's can be crippled by a small overvoltage on one input) I was designing a circuit a few years ago with a large number of analog muxes. The design... MD on Bouncing Short Beats Clean Short for Real-World Testing 5/21/2013 10:42:45 PM Re: Dodecahedron Testing: Woo, nice compendium of corners!!! :-) I still can recall how great it was when TI introduced their TL7705 reset controller – the first one AFAIK to do it right, and work under any weird voltage conditions. MD on Bouncing Short Beats Clean Short for Real-World Testing Next 5 messages + All messages All messages blog roll message boards chat 4/27/2013 10:33:39 AM Friday April 26th Live Chat here, 1230ET: Hey, interesting ideas, I would imagine T&M will move ever more closer to the world of Labview and automated test. Starngely, that LCR bridge that i posted has ATE features built-in and it is from 70's/early 80's! H. Sanders Sheriff 4/26/2013 2:31:03 PM Friday April 26th Live Chat here, 1230ET: I think that I have a test-board that I can futz around with. I will stay after work a bit and see what I can TDR. jason8957 Blogger 4/26/2013 2:28:42 PM Friday April 26th Live Chat here, 1230ET: I have this server on my desk with all my software on it and I can just cable it to any system that I want to mess with using x16 PCIe. jason8957 Blogger 4/26/2013 2:27:10 PM Friday April 26th Live Chat here, 1230ET: http://sine.ni.com/images/products/us/03221101_m.jpg jason8957 Blogger 4/26/2013 2:26:39 PM Friday April 26th Live Chat here, 1230ET: I have a server with the x16 MXIe card in it cabling to a PXIe chassis so that it can control the system remotely. jason8957 Blogger 4/26/2013 2:17:46 PM Friday April 26th Live Chat here, 1230ET: It's an external box with a PCIe cable? MD Blogger 4/26/2013 2:16:19 PM Friday April 26th Live Chat here, 1230ET: I use it all the time to connect to a server that I can remote desktop in to. jason8957 Blogger 4/26/2013 2:15:51 PM Friday April 26th Live Chat here, 1230ET: NI PXIe-8388 w 3m cable. x16 Gen2 MXI-Express for PXI Express Interface jason8957 Blogger 4/26/2013 2:15:41 PM Friday April 26th Live Chat here, 1230ET: I've been lurking. 73s till next time. cgervasi Apprentice 4/26/2013 2:14:39 PM Friday April 26th Live Chat here, 1230ET: Slow start turned into a great chat. I need to take off, but the chat remains open! See you around. MD Blogger Next 5 chats +		information resources sponsored content by Tektronix Creating Multi-SMU Systems with High Power System SourceMeter Instruments Application Note Parametric Curve Tracer Configurations Fundamentals of a Mixed Domain Oscilloscope Power Supply Measurement and Analysis Application Note Measurement Systems Signal Integrity: Important Factors to Consider Application Note The Basics of Serial Data Compliance and Validation Measurements All resources flash poll All polls twitter Follow us like us on facebook

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