Doh...

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I spent some time debugging yesterday... I use an LM358 as a level converter, and was getting no output from it... not a twitch.

 

So I changed it. Not a twitch.

So I changed the transistor it was driving. Not a twitch.

So I changed the resistor between the two. Not a twitch.

 

Eventually I realised the issue: there is a PCB choice to allow Vcc or Vin to supply the power to the 358. It works much better if I use the intended zero ohm resistor, and not a ten k...

 

Doh!

 

Neil (you can laugh now, and point at me laugh )

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Lol Neil, I won't be laughing at you! Being an amateur I have SEVERAL Doh! moments.

 

My last one was I built a little 555 circuit with jumpers and a variable resistor for a variable square wave to drive a stepper board I built out of recovered components from photo copiers. It was all built on Vero Board so no loose connections. Tested everything and it was working fine. Go for supper and come back, switch it on again and nothing! Start checking everything on both boards a section at a time and find the 555 is doing its job no problem and feeding to the stepper motor controller chip but still no output. After a little head scratching I eventually look under my keyboard at the steel ruler just sticking out a little and realize, the damned thing wasn't visible but was under the stepper controller chip dual row of pins, shorted it out and blew it. Doh! laugh

 

EDIT: Typos

Wayne

East London
South Africa

 

  • No, I am not an Electronics Engineer, just a 54 year old hobbyist/enthusiast
  • Yes, I am using Proteus to learn more about circuit design and electronics
  • No, I do not own a licensed copy of Proteus, I am evaluating it legitimately
  • No, I do not believe in software or intellectual property piracy or theft
Last Edited: Sat. Jul 17, 2021 - 07:25 AM
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My remote ATMEGA48 was SPI connected, and refuse to do buzzing, exhibit more unexpected stuff, like restart, to conclude, found no Vcc connection.

 

I have Doh! moments everyday, I mastered on them.

 

Think that I tried everything possible to destroy an ATMEGA on various projects, and failed. This chip is designed to resist any assault by a RDU.

 

 

Last Edited: Sat. Jul 17, 2021 - 08:10 AM
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grohote wrote:

 

I need one of those, where do I apply? smiley

Wayne

East London
South Africa

 

  • No, I am not an Electronics Engineer, just a 54 year old hobbyist/enthusiast
  • Yes, I am using Proteus to learn more about circuit design and electronics
  • No, I do not own a licensed copy of Proteus, I am evaluating it legitimately
  • No, I do not believe in software or intellectual property piracy or theft
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Experience is a collection of mistakes.

Ross McKenzie, Melbourne Australia

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WayneZA wrote:
I need one of those, where do I apply?

How I can help, please. I have exclusive patents rights, and I am not the proud owner of. To illustrate, just the latest "rubbish" affair. Do I need it-not. I might be oversensitive, hot-blooded, but I should not do such things, no Sir.

Last Edited: Sat. Jul 17, 2021 - 10:41 AM
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valusoft wrote:
Experience is a collection of mistakes.

Easy to tell. Remember my first crossing-road in Melbourne. I was almost got splashed to the first car, my first experience with left-driving failed to be the last one.

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Doh pt 2... an ever so slight, so slight as to be imperceptible, error caused some idiot to design a level converter with an inverting output... which was not the intent crying

 

Fortunately, the STM32L073 UART has the ability to invert the input in software... dodged that one!

 

Neil

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barnacle wrote:
some idiot
Who no doubt will remain nameless...

Ross McKenzie, Melbourne Australia

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valusoft wrote:
Who no doubt will remain nameless...

 

Ahh, but those "who shall remain nameless" seldom do. Ask me how I know. laugh

Wayne

East London
South Africa

 

  • No, I am not an Electronics Engineer, just a 54 year old hobbyist/enthusiast
  • Yes, I am using Proteus to learn more about circuit design and electronics
  • No, I do not own a licensed copy of Proteus, I am evaluating it legitimately
  • No, I do not believe in software or intellectual property piracy or theft
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Duh... a deer....   a female deer!     

 

 

Keys to wealth:

Invest for cash flow, not capital gains!

Wealth is attracted, not chased! 

Income is proportional to how many you serve!

If you want something you've never had...

...you must be willing to do something you've never done!

Lets go Brandon!