MWagner_MA

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Sr. Electrical Engineer

Electronic Design Engineer (BSEE), 25yr industry veteran with experience in circuit and PWB engineering for instrumentation and mixed-signal design. Sensor interfacing, and precision analog a specialty bringing high reliability design to commercial projects at low cost. I also hold an FAA certificate for Single engine, Land, Instrument airplane (pilots license), and an amateur radio license. Hobbies include building and flying radio controlled aircraft, and building home electronic projects. Find me on Linked-In at: www.linkedin.com/in/mark-wagner-31965416


MWagner_MA

's contributions
  • 05.26.2017
  • Is iPad scope worth professional pricetag?
  • Welcome to the "makers" thinking their professional engineers. 16K of memory, what are we using a Commodore 64? Obviously the concept of "aliasing" among other terms is foreign to them. When I see omissions like this you have to wonder about how solid the rest of the engineering was to build the product. If if you ignore the market research - anyone with experience using digital O-Scopes know you need a LOT more than that. Even 100K, as I have seen on some other recent offerings, is way too small. Thanks for the detailed review Mike.
  • 01.31.2017
  • If it smells fake, it probably is
  • Martin, how true. We are constantly pushing our marketing department to establish requirements or boundaries of what they expect our products to do. Marketers naturally don't want to do that because,then they may have to say "no, we can't do that" to a potential customer. Instead, they try to push fuzzy specs, then rail at engineering to make the product work for this one customer. Sound familiar? Reputable companies drive a stake in the sand and state what you can expect from a product time and again.
  • 01.06.2017
  • Properly ground your circuits
  • With all due respect to the authors as renowned experts in the field, the statement "A PCB does not need an analog ground plane and a digital ground plane" is accurate when only 1 or two supplies are used. When there are multiple supplies that are isolated, it is best to focus on return currents as the article mentions. Splitting planes is necessary to avoid RF leakage paths, and the overlapping of such planes is closely controlled as well. I like to avoid the NEVER, and ALWAYS statements as it usually is impractical to state all the assumptions that the statement is predicated on. I'm a big fan and have been a student of your work for years. Thanks for your contributions to the field.
  • 12.29.2016
  • Near-field scanning: useful or misleading?
  • thanks Ken. My confusion was caused by the fact that by using the probes mentioned, the signal has already radiated. So my question then becomes how to consider the threshold for a "problem" to occur at a distance. Noise currents through a decoupling capacitor will not radiate (much) because the loop areas, if properly designed, will prohibit that from occurring.
  • 12.29.2016
  • Near-field scanning: useful or misleading?
  • So where would you go to understand more about understanding what will propagate, and what will not? Specifically, I would like to understand how this consideration would apply in PCB design. (nice article thanks!)
  • 12.14.2016
  • Real world RS-485: Low power, low EMI
  • I'll explain a little more in my next article including more about noise modeling. That will help explain why the ground in RS-485 isn't as much as a problem as it may seem.
  • 12.14.2016
  • Real world RS-485: Low power, low EMI
  • You brought up a partially comment about the grounding of RS-485, however, where this network is vastly superior to RS-232 is that it input impedance is only 499(in my article) or lower. The ground problem IS improved, because the return current is through the diff network when using termination - NOT the ground at the opposite end. The only reason for the ground is to maintain the common mode voltage which can be managed with LC networks for noise immunity. The input impedance of an RS-232 receiver can be as high as 10K, which makes it much more susceptible to EMI. Correctly done, RS-485 will work in more noise prone environments than 232, thus military applications are frequently differential networks like this, not 232.
  • 05.27.2016
  • 10 drones you’ll want to own
  • I agree. Flying a drone is like flying a helicopter...no grace like a Supermarine Spitfire :-) I would definitely feel like cheating putting a gyro in an airplane, but I can understand the attraction for some. Especially trying to get all this gear in the air and stabilize it.
  • 12.07.2016
  • The mythical software engineer
  • Sorry but firmware and software is just semantics. Similar tools and methodologies apply. What's different is the hardware it runs on and perhaps amount of memory available. The lines are getting blurred for the hardware as embedded systems many times look like PC's without the keyboard/mouse/trackpad. And you can ONLY learn something in one type of school...really? Please tell that the groups of programmers that are mathematicians and electrical engineers.