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What's gone well for you recently? No matter how big or small.

cstanton

I took a couple of weeks off work, as much as you can when it's in the middle of a lockdown pandemic in the united kingdom, and I had a couple of wins myself.

blown up chip

For many years I kept hold of a computer hard drive that had died on me, of all things the microcontroller on the control board blew itself up. I had looked for a replacement control board online and at the time they cost £100+ because this was such a common problem, however recently I looked again and found that it was on ebay for £6, with a 50/50 chance of being the wrong model.

 

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I took a gamble. A direct swap of the board isn't what works with this, as you can even see highlighted in the ebay listing screenshot, each drive has a BIOS chip on it flashed with the necessary settings for the platters, sectors, etc. of the hard drive. Without the right BIOS chip, you'll just get garbled data or clicking.

 

Time for a bit of desoldering and kapton tape.

 

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As luck would have it, it worked! My hard drive was brought back to life, and I was able to recover my data once more.

 

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I'd say that is a good 'win' for £6 and a reflow station image

 

What's gone well for you recently?

  • I've just completed this:

     

    image

     

    It measures the sensitivity of a multi axis piezo electric accelerometer at frequencies between 30 and 200 Hz.

    The reference accelerometer (white thing on top of the little shaker table) has a vacuum port so the device

    under test can be pulled down onto the reference without glue or clamps.

    The box contain all the electronics to drive the shaker and condition and filter the signals from the DUT and

    the reference. It uses an STM32F407 processor which controls everything and implements tracking digital filters with

    about 0.2Hz -3dB bandwidth and 20Hz -70dB bandwidth.

    image

     

    I had a bit of a crisis during manufacture of the reference accelerometers -  the mill died as it was machining the

    accelerometer bodies (Y axis servo amplifier blew, with noise but no smoke). Haas did a good job fixing it: I emailed them

    on Sunday afternoon and it was back and running the next Friday lunchtime - so only out of action for less than a

    week.

    All that remains to do is formal calibration and it will be off to its new home.

     

    MK

  • in reply to parasquid

    It's always good to have an assistant !

     

    MK

  • in reply to dougw

    Eh not necessarily. A spindle motor that's a bit jammed due to wearing bearings will draw high start-up currents which can cause those chips to fail given enough start-stop cycles. Likewise, a noisy DC power supply with lots of ripple may give them enough stress.

     

    The chip itself (ST SMOOTH) is actually a combination motor driver chip if I recall correctly - does the spindle motor and head positioning voice coil motor. It's one of the few chips on the PCB that actually deals with the ATX 12V rail and the bulk of the power running through the drive.

     

    The EEPROM chip contains the drive parameters, sometimes even a snippet of firmware, but the bravest of souls could try desoldering it with the "solder blob" and wick method if they don't have a hot air gun - it usually works just fine presuming you're quick.

     

    - Gough

  • in reply to rsc

    Congrats! That's awesome!! Nice results : )

    In some ways I guess it's good that the exams have been pushed to operate in this way, one of the benefits of Zoom'd amateur radio exams I suppose is that potentially one no longer has to wait for the local club (or especially if people are far from a club), people could sit it anywhere virtually to a remote club, perhaps even overseas : ) I wonder if anyone has done that, and what the regulations are around that.

  • in reply to parasquid

    What lives in the big plastic box  under the big monitor ?

     

    MK

  • I used to have a standing desk in the office, and after months of slouching on my chair due to working from home I decided to get my posture back up and set up a standing desk at home.

    image

    Wires are still messy and there's still some stuff that need to be organized, but using a standing desk works wonders for productivity.

     

    Biggest benefit: you can feel when you're tired and need an actual break, instead of just browsing mindlessly on youtube or facebook (or ... gasp ... element14 community).

  • in reply to shabaz

    > Great job with the hard disk! What reflow station did you use incidentally?

     

    I likely meant rework rather than reflow, though I've seen the two used interchangeably.

     

    If I was able to access Leeds Hackspace, I would have used this:

     

    https://uk.farnell.com/tenma/21-10130-uk-eu/rework-station-900w-220v-uk-eu/dp/2062633

     

    image

     

    But because I can't... and I have a limited budget, I bought this from aliexpress:

     

    image

     

    Which did the job, though it has limits.

  • Good job with the hard drive!

     

    In my job, I'm a hardware engineer but for certain reason I was asked to make some low level drivers, oh men, my coding skills are awful and I had some difficulties with a RFID transceiver, then I had to make some function for read a tag, It was really hard to me because I have little experience with this kind of coding, but at the end with some help I was able to make it work and read the tag.

  • I've been thinking about this since Jr. High School - getting my Amateur Radio operators license.

    One of the local clubs put on a one day zoom class crash course with the exam following the same day.

    Passed with %100.

    73's

    Scott

    KD9QOG