Design Con 2015

zeeglen

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CC&BW

Old-timer who grew up with vacuum tubes and therefore have been amazed and fascinated by the many advances in the electronics industry since.


zeeglen

's contributions
  • 01.14.2015
  • Green Screens & Ham (Apologies to Dr. Seuss)
  • The electronics bug bit me when I was 8 years old, that led to me getting my ham licence as soon as the law allowed at 15 yrs. Before that I listened to shortwave on the living room all-band hi-fi system, it lacked a BFO so to hear the hams using SSB and to get CW practice I very carefully tuned a Heathkit SG8 signal generator (a gift from a neighbour) to the same frequency. Also discovered the SG8 could be used as a (slightly illegal) AM transmitter when a carbon mic from a telephone was inserted between the output and a wire antenna in the attic. Was VE3EUK, VE4GC, VE3PFI, VE3RZ. No longer active, maybe one of my grandkids will inherit the SB101 transceiver. An interesting film about ham radio leading to an engineering/astronomy career is 'Contact' starring Jodie Foster and based on the novel by Carl Sagan.
  • 11.05.2013
  • DC distribution in your house and 42-V cars
  • @DIDEFIXIT I did that once - only once! The lamp was clipped to the headboard of my bed. I unscrewed the light bulb and played with the on-off switch, push-on-push-off. Then trying to screw the lightbulb back in could not find the socket in the dark, so felt for it with my finger. The switch was in the push-on condition. I found the socket. I am still alive. The lamp socket was 240 VAC in France. I was 6 years old at the time, but I learned a valuable lesson.
  • 12.30.2014
  • Back in the backplane
  • "I work with system architects, mechanical engineers, and PCB designers." Good article, and the above quote sums up one of the design aspects nicely. The backplane guy is central to the design effort and has to coordinate initial design and ongoing changes between a lot of different people, as well as encourage those people to consider the mechanical aspects from the start. For example, Annie designs card A which talks to Charlie's card C through Bob's backplane. Bob tells Annie and Charlie to place their interconnecting blocks in the same areas of their respective cards and to match the pinouts since Bob will only carry between the same pins of the respective card slots. Slot 1 pin 3C connects to slot 7 pin 3C and no other. This keeps all traces horizontal and avoids wasting layers and vias on un-necessary vertical traces. Oh, and make sure Annie and Charlie understand the implications of flight time across the backplane for their digital timings. It is also Bob's duty to warn mechanical designers about other limitations, such as optical ribbon cables that do NOT bend sideways and require a minimum bend radius. This sets the size of the cards for a given shelf depth since space must be reserved behind the backplane for the attached optical cables. Wherever possible Bob needs to define attached cables connector pinouts to match trace flow from card slot connectors - this allows nice parallel traces instead of multiple criss-crossing layers. I once worked with a designer who chose the pinouts for a 2-slot adapter backplane at random, then went on vacation. Since the 2nd card of the set had not yet been laid out, I sketched the traces and re-arranged the pinouts for 2 layers instead of multiple layers.
  • 12.01.2014
  • Bad-bulb finder fixes Christmas lights
  • "this tester won't help you find a bulb whose shorting bar has activated" Well, if the shorting bar has activated this tester would not be required for further testing, would it?
  • 10.03.2014
  • The scope...from Hell!
  • I would laugh if this was not so scary - read your review on Amazon just this morning, and only 6 hours later am already seeing ads for the DPO2024B on farcebook. Corporate USA is watching me...
  • 10.03.2014
  • The scope...from Hell!
  • Wonderful review - tells it like it is! I think a big part of the problem is user interfaces designed by those who have not have much experience using oscilloscope user interfaces. Growing up with the experience gained from the UI of video games is no substitute for growing up using oscilloscopes. Hopefully your observations and suggestions for improvement will result in furthering of their future skills.
  • 10.03.2014
  • The scope...from Hell!
  • Right! Except when the only floppy-equipped machines in the corp are the scopes. Try copying a screen image into a word file when the PC does not have a floppy drive. And no PC in the entire corp has a floppy drive. Now what?
  • 10.03.2014
  • The scope...from Hell!
  • To which the bean-counter response is "You did great on your last project with that same scope. Why do you need a new scope for your new project?" I guess one has to fail substantially before the need for decent test equipment gets noticed - in a negative way.
  • 10.03.2014
  • The scope...from Hell!
  • Oh yeah, did the self-cal many times. No improvement. I suspect the self-cal was simply a quack panacea that did nothing.