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are drawing normal schematics a dying art?

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vk6zgo:

--- Quote from: Zero999 on November 29, 2021, 11:56:17 am ---
--- Quote from: eti on November 29, 2021, 10:02:26 am ---
--- Quote from: Zero999 on November 29, 2021, 09:50:45 am ---
--- Quote from: Berni on November 29, 2021, 06:50:26 am ---So as long as you need anything more than just a constant frequency blink it will actually be cheaper to use a tiny 6 pin MCU, also its more compact. I went down the path of designing an analog circuit for a easy task, only to get half way there, realize this takes a lot of components to do properly, then throw it away and replace it with a MCU.
--- End quote ---
You can't get much cheaper than a Schmitt trigger IC, such as the 74HC1G14 + RC circuit and costs less than the cheapest MCU, in small quantities.

If all I wanted was a flashing LED, just use a self-flashing LED: no discrete components, or coding required!

--- End quote ---

I remember seeing flashing red LEDs in “Tandy” in the UK, back in the 90s, for about £4, and I recall thinking what a ripoff it was 😁

It was, but they’re great.

--- End quote ---
Everything was expensive in Tandy. Basic components, such as a plain old TO-92 BJT, 741, 555 timer etc. cost around £1 each. They used to be sold in blister packs with the component sealed inside a vacuum formed bubble, stuck to a piece of cardboard, with a basic datasheet printed on the back. Worse still, the packaging wasn't even ESD proof. I'm pretty sure I had bought faulty components from Tandy, but as I was only 12 at the time and a complete beginner, I didn't have the confidence to complain, as I thought it might've been my fault.

I remember seeing a few empty packets in the store. Either someone had stolen the components, or the glue had started to fail, allowing them to fall on the floor and presumably vacuumed up. They probably lost as many parts, as they sold.

I remember discovering Maplin, which was much cheaper and sold a greater range of components, but there wasn't one in my town, so my dad occasionally drove me 10 miles to go there. Eventually a Maplin did open near me, but by then Tandy had gone and it had deteriorated to the point of being useless, for most things.

--- End quote ---

In Oz, sometimes Tandy would have some weird bit that nobody else had, but at an exorbitant price, or other times, it was just easier to "bite the bullet" & pay up for a common component, rather than drive a couple of suburbs away to Dick Smith.

On the former point, the bloke next door came over with his daughter's intermittent car radio for me to "take a look at".

All pretty standard, except for a largish DIP audio amp IC, which turned out to have a temperature sensitive fault, & more importantly, was "unobtainium" in Oz.(this was pre-Internet!)

After looking everywhere, I was just about to give up, when whilst browsing in Tandy, I saw an audio IC in a vacuum pack, that someone had put on the hook with the cardboard back, showing a suggested application, facing out.

It was "near as dammit" the same as the one I needed, except in a totally different, single inline package, with a heatsink tab on top.

As luck would have it, there was enough room to attach it to the radio's side panel, & by using  a bunch of  conductors stripped out of a multi cored phone cable, I was able to do a reasonably neat job of connecting it up.

It went "first go"---no more temperature sensitive failures.

No more "Mr Fixit" for me, either, I pleaded too much work from my real job!

 

eti:

--- Quote from: vk6zgo on November 30, 2021, 05:29:09 am ---
--- Quote from: Zero999 on November 29, 2021, 11:56:17 am ---
--- Quote from: eti on November 29, 2021, 10:02:26 am ---
--- Quote from: Zero999 on November 29, 2021, 09:50:45 am ---
--- Quote from: Berni on November 29, 2021, 06:50:26 am ---So as long as you need anything more than just a constant frequency blink it will actually be cheaper to use a tiny 6 pin MCU, also its more compact. I went down the path of designing an analog circuit for a easy task, only to get half way there, realize this takes a lot of components to do properly, then throw it away and replace it with a MCU.
--- End quote ---
You can't get much cheaper than a Schmitt trigger IC, such as the 74HC1G14 + RC circuit and costs less than the cheapest MCU, in small quantities.

If all I wanted was a flashing LED, just use a self-flashing LED: no discrete components, or coding required!

--- End quote ---

I remember seeing flashing red LEDs in “Tandy” in the UK, back in the 90s, for about £4, and I recall thinking what a ripoff it was 😁

It was, but they’re great.

--- End quote ---
Everything was expensive in Tandy. Basic components, such as a plain old TO-92 BJT, 741, 555 timer etc. cost around £1 each. They used to be sold in blister packs with the component sealed inside a vacuum formed bubble, stuck to a piece of cardboard, with a basic datasheet printed on the back. Worse still, the packaging wasn't even ESD proof. I'm pretty sure I had bought faulty components from Tandy, but as I was only 12 at the time and a complete beginner, I didn't have the confidence to complain, as I thought it might've been my fault.

I remember seeing a few empty packets in the store. Either someone had stolen the components, or the glue had started to fail, allowing them to fall on the floor and presumably vacuumed up. They probably lost as many parts, as they sold.

I remember discovering Maplin, which was much cheaper and sold a greater range of components, but there wasn't one in my town, so my dad occasionally drove me 10 miles to go there. Eventually a Maplin did open near me, but by then Tandy had gone and it had deteriorated to the point of being useless, for most things.

--- End quote ---

In Oz, sometimes Tandy would have some weird bit that nobody else had, but at an exorbitant price, or other times, it was just easier to "bite the bullet" & pay up for a common component, rather than drive a couple of suburbs away to Dick Smith.

On the former point, the bloke next door came over with his daughter's intermittent car radio for me to "take a look at".

All pretty standard, except for a largish DIP audio amp IC, which turned out to have a temperature sensitive fault, & more importantly, was "unobtainium" in Oz.(this was pre-Internet!)

After looking everywhere, I was just about to give up, when whilst browsing in Tandy, I saw an audio IC in a vacuum pack, that someone had put on the hook with the cardboard back, showing a suggested application, facing out.

It was "near as dammit" the same as the one I needed, except in a totally different, single inline package, with a heatsink tab on top.

As luck would have it, there was enough room to attach it to the radio's side panel, & by using  a bunch of  conductors stripped out of a multi cored phone cable, I was able to do a reasonably neat job of connecting it up.

It went "first go"---no more temperature sensitive failures.

No more "Mr Fixit" for me, either, I pleaded too much work from my real job!

--- End quote ---


Aaah! Car radios! I absolutely adore that format and the compact nature of clever mechanical things coupled with a very dense electronics. I am now casting my mind back to my teenager years where my boy racer friends would ask me “please wire up my stereo, Matthew.” (muggins  here couldn’t say no, 🙃) or the DREADED “Moss” car alarms, which even at the tender age of 17, I was perceptive enough to sense were a “trend”, and utter junk! 😝

Car electrics are tedious and cramped, and the crusty, crude wiring looms which are nothing but a bunch of wires encased in spiral-wound insulation tape and the endless mismatched and poorly made bodge connections which silently tell the history of the owners of the logbook. Ughhhh

johnboxall:

--- Quote from: vk6zgo on November 30, 2021, 05:29:09 am ---Everything was expensive in Tandy.

--- End quote ---

A free 9V battery every month made up for it. Tandy did some things right - as a kid I would pay off those pocket BASIC computers using lay-by. Would have hundreds of the yellow hand-written slips over my high-school days.

james_s:

--- Quote from: Zero999 on November 29, 2021, 11:56:17 am ---Everything was expensive in Tandy. Basic components, such as a plain old TO-92 BJT, 741, 555 timer etc. cost around £1 each. They used to be sold in blister packs with the component sealed inside a vacuum formed bubble, stuck to a piece of cardboard, with a basic datasheet printed on the back. Worse still, the packaging wasn't even ESD proof. I'm pretty sure I had bought faulty components from Tandy, but as I was only 12 at the time and a complete beginner, I didn't have the confidence to complain, as I thought it might've been my fault.

I remember seeing a few empty packets in the store. Either someone had stolen the components, or the glue had started to fail, allowing them to fall on the floor and presumably vacuumed up. They probably lost as many parts, as they sold.

I remember discovering Maplin, which was much cheaper and sold a greater range of components, but there wasn't one in my town, so my dad occasionally drove me 10 miles to go there. Eventually a Maplin did open near me, but by then Tandy had gone and it had deteriorated to the point of being useless, for most things.

--- End quote ---

It was relatively expensive, but there wasn't anywhere else around, at least not that I knew of at the time. Radio Shack was in every shopping mall and when I was a kid it was the most interesting store there was in the mall and always the place I wanted to go to first whenever I was in one. The problem I had with them was not the prices but the fact that they almost NEVER had all the parts needed to build ANYTHING, even the projects in their own books they sold. You could get a lot of common ICs and stuff like LEDs and switches and project boxes, but they never seemed to have all of the values of resistors or capacitors I needed, it was always something. Eventually I learned about Digikey somehow, I think they randomly sent me a catalog but even then I had to make a list and get my mom to call and order things because I didn't have a checkbook or credit card when I was a kid.

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