Interlude #15: Making a USB Power Cable for My ATtiny85 from 4x AA Battery Pack | In The Lab

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In this video we make a cable to connect a 6V battery pack with a 9V adapter to a USB Type-A female socket, which we can then use to connect a USB Type-A male through Type-B micro for powering my microcontroller.

We use the METCAL PS-900 Soldering Station to solder our cables.

We use the EEVblog BM2257 Digital Multimeter to test voltage and continuity.

We use the Horusdy Soldering Station with Hot Air Gun to shrink our heat shrink.

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Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

Tungfull TH-161 Rotary Tool Accessory SetThis is an image of the product.notes

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Are you the right person to design complex electronic boards?

This evening I watched Are you the right person to design complex electronic boards? which discusses what being a professional electronics designer entails. I particularly liked this slide which compares and contrasts the books a hobbyist might read versus what a professional might read.

Texas Instruments Datasheets

I was watching The Differential Pair Becomes an Op-Amp – Transistors 101, episode 18 and they mentioned this datasheet: https://ti.com/lit/ds/symlink/lm358.pdf. That URL looks very hacker friendly to me, if you know what you’re looking for you can probably guess the URL! I haven’t tried this in anger yet, this is just a note for Future John.

Introducing Maxitronix 30in1 | Maxitronix 30in1 | Learning Electronics In The Lab With Jay Jay

This post is part of my video blog and you can find more information about this video over here.

You can support this channel on Patreon: patreon.com/JohnElliotV

In this video we introduce the Maxitronix 30in1.




Thanks very much for watching! And please remember to hit like and subscribe! :)


Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

JST XH2.54 6pin Pre-crimped ConnectorThis is an image of the product.

Let’s go shopping!

New Zealand’s $16 Billion Public Health System Runs on a Single Excel Sheet

This is a note for Future John: New Zealand’s $16 Billion Public Health System Runs on a Single Excel Sheet.

From the report:

Notably, one major issue was through a significant reliance on the use of an Excel file to manage the consolidated financials of the organisation. This spreadsheet was the primary data file used by HNZ to manage its financial performance. It consolidated files from each district into a single spreadsheet, and key reports, such as the monthly finance report, were produced from it. The use of an Excel spreadsheet file to track and report financial performance for a $28bn expenditure organisation raises significant concerns, particularly when other more appropriate systems are present on the IT landscape.

This Excel file is flawed in that:

  • Financial information was often ‘hard-coded,’ making it difficult to trace to the source or have updated data flow through.
  • Errors such as incorrectly releasing accruals or double-up releases were not picked up until following periods.
  • Changes to prior periods and FTE errors in district financial reporting Excel submissions, would not flow through to consolidated file.
  • The spreadsheet can be easy to manipulate information as there is limited tracking to source information where information is not flowing directly from accounting systems.
  • It is highly prone to human error, such as accidental typing of a number or omission of a zero.

The cumbersome process of collecting data also meant monthly financial reporting usually took 12-15 days to consolidate and 5 days to analyse. Adding to that the time associated with the creation of the monthly finance reports and circulation of these to the Board, there was an inevitable challenge of obtaining real-time financial information from one source of truth.