ESC 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
  • 02.20.2015
  • Black Friday: The Avro Arrow tragedy
  • Michael, was your blog inspired perhaps by the EETimes blog Mortal Motorola by Alan Patterson last week? http://www.eetimes.com/author.asp?section_id=36&doc_id=1325699 The Avro Arrow is the first thought that came to mind after I read this, and I spent some time on Wikipedia reviewing the story of the ill-fated Arrow. I was a kid at the time but I still remember my father (RCAF captain) complaining bitterly about the Arrow's demise.
  • 01.27.2015
  • Don’t neglect the humble battery connector
  • Remember the old Heathkit H8 computer? The heat-sink-bracket mounted TO-220 5V regulators were connected through flying leads to the PCBs, but used a connector slipped onto the regulator pins. After about a year a bulletin come out that intermittent failures could be cured by soldering the wires directly to the regulators and throwing away the connector.
  • 02.05.2015
  • Fixing a mainframe with a lunch bag
  • Long ago while in college I worked part-time at a TV repair shop. This was before TV sets became throw-away items. The tuners were electromechanical and consisted of a rotary drum with 12 removable sticks each wound with inductor windings to select 1 of 12 channels. Each stick had about a dozen gold plated fixed contacts (bumps) which would line up with a stationary strip of flexible gold plated contacts that pressed against the bumps on the sticks as they were rotated into position. The whole assembly was hand-driven by a large knob on the front panel. These tuners needed periodic cleaning to remove dust and grime that would make the picture jitter when the knob was barely touched. I was doing a service call and saw the tuner had this classic problem so I told the lady it needed cleaning and I could do it in the home for an additional $6. She said it had just been cleaned, so I asked who did it. "My husband's friend, a mechanic." "What did he use?" I asked. "Sandpaper". In those days auto mechanics used sandpaper to clean ignition points. "Sorry lady, that tuner is now toast."
  • 02.04.2015
  • Fluorescent Light Scam
  • "There's a video of this somewhere on the internet about making red ink green or similar" It's called "The Expert", is absolutely hilarious and is on youtube.com. The gist is the meeting where the management types won't believe the engineer when he claims it is impossible to draw 7 red lines, all perpendicular to each other, some with green ink and some with transparent ink.
  • 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...