Topics

Very cheap, 24 cent microprocessors. #firmware #i2c

Tom, wb6b
 

Hi,

I stumbled upon these microprocessor chips at just $0.24 each. What is really compelling about these chips is they have an 8 channel A/D converter with 12 bit resolution. That is better than the Nano at 10 bits. And the A/D is many times faster.

Seems great where you would want to measure things in your radio, be able to digitize them and send the readings to other parts of the system, such as the Raduino. With a little bit of control functionally mixed in. 

https://direct.nuvoton.com/en/ms51fb9ae

Looks like the old time 8051 processors did not die, they still live on in inexpensive yet faster processor chips. I suppose there must be a warehouse of assembly code and possibility C code piled up on-line or elsewhere for these 8051 and derivative chips.

The chip has a built in factory trimmed 24mhz RC clock oscillator and a 10Khz RC oscillator for a low power mode. And a UART, assorted timers, GPIO and such. Looks like a battery (or other power supply) and maybe a small power bypass cap and you are good to go. 

Looks like a great chip for things that could be cobbled together with a few lines of code and seemed so trivial that using a microprocessor chip seems overkill. (Although it will handle way more than just a few lines of code.)

Too bad it does not have a built in temperature sensor (I guess they have to leave something out for 24 cents). You could have used it to control your cooling fan and it might have been cheaper than a thermistor. I might make a dimmable red led light for the spotter scope graticule on my telescope. Hard to think of a much more trivial and previously though to be overkill project for a microprocessor. 

I ordered some for my parts box along with a $25 development board, with a built-in programmer, that looks like I can use to develop and program the chips with.

Hopefully there will be open source and manufacture supplied tools to develop and upload the programs, without needing expensive commercial development tools. I believe that is the case. It should be possible to cobble together a free toolchain if it does not already exist. If anyone else has done development with the various recent 8051 derivative chips, it would be interesting to hear about your thoughts. 

It will be fun to go back in time and visit to the good old days of very simple chips and instruction sets; but at the same time be modern.

I discovered this chip because I bought one of the WiFi relay modules on eBay and besides the WiFi module (ESP-01), this chip (actually the older version) was used to turn the relays on and off based on hex codes sent over a serial link.

I'll know more when everything arrives and can play with the development board.

Tom, wb6b

Ken Hansen
 

Interesting, but from what I saw these are surface mount parts, many hams are put off by projects that rely on such parts.

Ken, N2VIP

On Mar 4, 2020, at 23:05, Tom, wb6b <wb6b@...> wrote:

Hi,

I stumbled upon these microprocessor chips at just $0.24 each. What is really compelling about these chips is they have an 8 channel A/D converter with 12 bit resolution. That is better than the Nano at 10 bits. And the A/D is many times faster.

Seems great where you would want to measure things in your radio, be able to digitize them and send the readings to other parts of the system, such as the Raduino. With a little bit of control functionally mixed in. 

https://direct.nuvoton.com/en/ms51fb9ae

Looks like the old time 8051 processors did not die, they still live on in inexpensive yet faster processor chips. I suppose there must be a warehouse of assembly code and possibility C code piled up on-line or elsewhere for these 8051 and derivative chips.

The chip has a built in factory trimmed 24mhz RC clock oscillator and a 10Khz RC oscillator for a low power mode. And a UART, assorted timers, GPIO and such. Looks like a battery (or other power supply) and maybe a small power bypass cap and you are good to go. 

Looks like a great chip for things that could be cobbled together with a few lines of code and seemed so trivial that using a microprocessor chip seems overkill. (Although it will handle way more than just a few lines of code.)

Too bad it does not have a built in temperature sensor (I guess they have to leave something out for 24 cents). You could have used it to control your cooling fan and it might have been cheaper than a thermistor. I might make a dimmable red led light for the spotter scope graticule on my telescope. Hard to think of a much more trivial and previously though to be overkill project for a microprocessor. 

I ordered some for my parts box along with a $25 development board, with a built-in programmer, that looks like I can use to develop and program the chips with.

Hopefully there will be open source and manufacture supplied tools to develop and upload the programs, without needing expensive commercial development tools. I believe that is the case. It should be possible to cobble together a free toolchain if it does not already exist. If anyone else has done development with the various recent 8051 derivative chips, it would be interesting to hear about your thoughts. 

It will be fun to go back in time and visit to the good old days of very simple chips and instruction sets; but at the same time be modern.

I discovered this chip because I bought one of the WiFi relay modules on eBay and besides the WiFi module (ESP-01), this chip (actually the older version) was used to turn the relays on and off based on hex codes sent over a serial link.

I'll know more when everything arrives and can play with the development board.

Tom, wb6b

 

I am interested, can u suggest a simulator for it for firmware dev. on a windows PC?
--
AncelB, MIT EE6002

Jack, W8TEE
 

Mornin' Ken:

I agree with your statement, and that's really sad because most hams could easily do SMD parts. Farhan uses 1206 parts and even my 76 year old eyes and hands can work with them. They should invest $1.25 in an SMD practice kit (e.g., eBay 283799161850) and give it a try. I'll bet they would be surprised at how easy it is, plus kits using SMD parts are likely less expensive than a thru-hole equivalent.

Jack, W8TEE

On Thursday, March 5, 2020, 9:27:21 AM EST, Ken Hansen <ken@...> wrote:


Interesting, but from what I saw these are surface mount parts, many hams are put off by projects that rely on such parts.

Ken, N2VIP

On Mar 4, 2020, at 23:05, Tom, wb6b <wb6b@...> wrote:

Hi,

I stumbled upon these microprocessor chips at just $0.24 each. What is really compelling about these chips is they have an 8 channel A/D converter with 12 bit resolution. That is better than the Nano at 10 bits. And the A/D is many times faster.

Seems great where you would want to measure things in your radio, be able to digitize them and send the readings to other parts of the system, such as the Raduino. With a little bit of control functionally mixed in. 

https://direct.nuvoton.com/en/ms51fb9ae

Looks like the old time 8051 processors did not die, they still live on in inexpensive yet faster processor chips. I suppose there must be a warehouse of assembly code and possibility C code piled up on-line or elsewhere for these 8051 and derivative chips.

The chip has a built in factory trimmed 24mhz RC clock oscillator and a 10Khz RC oscillator for a low power mode. And a UART, assorted timers, GPIO and such. Looks like a battery (or other power supply) and maybe a small power bypass cap and you are good to go. 

Looks like a great chip for things that could be cobbled together with a few lines of code and seemed so trivial that using a microprocessor chip seems overkill. (Although it will handle way more than just a few lines of code.)

Too bad it does not have a built in temperature sensor (I guess they have to leave something out for 24 cents). You could have used it to control your cooling fan and it might have been cheaper than a thermistor. I might make a dimmable red led light for the spotter scope graticule on my telescope. Hard to think of a much more trivial and previously though to be overkill project for a microprocessor. 

I ordered some for my parts box along with a $25 development board, with a built-in programmer, that looks like I can use to develop and program the chips with.

Hopefully there will be open source and manufacture supplied tools to develop and upload the programs, without needing expensive commercial development tools. I believe that is the case. It should be possible to cobble together a free toolchain if it does not already exist. If anyone else has done development with the various recent 8051 derivative chips, it would be interesting to hear about your thoughts. 

It will be fun to go back in time and visit to the good old days of very simple chips and instruction sets; but at the same time be modern.

I discovered this chip because I bought one of the WiFi relay modules on eBay and besides the WiFi module (ESP-01), this chip (actually the older version) was used to turn the relays on and off based on hex codes sent over a serial link.

I'll know more when everything arrives and can play with the development board.

Tom, wb6b

--
Jack, W8TEE

Arv Evans
 

Tom

And they even have a dev board that looks a little like the Arduino Nano...


But at $20 each the are not going to sell many.  My guess is that with the low
price per CPU someone will come up with a pin-compatible Arduino version.

Thanks for the pointer to this product. 

Arv
_._



On Wed, Mar 4, 2020 at 10:05 PM Tom, wb6b <wb6b@...> wrote:
Hi,

I stumbled upon these microprocessor chips at just $0.24 each. What is really compelling about these chips is they have an 8 channel A/D converter with 12 bit resolution. That is better than the Nano at 10 bits. And the A/D is many times faster.

Seems great where you would want to measure things in your radio, be able to digitize them and send the readings to other parts of the system, such as the Raduino. With a little bit of control functionally mixed in. 

https://direct.nuvoton.com/en/ms51fb9ae

Looks like the old time 8051 processors did not die, they still live on in inexpensive yet faster processor chips. I suppose there must be a warehouse of assembly code and possibility C code piled up on-line or elsewhere for these 8051 and derivative chips.

The chip has a built in factory trimmed 24mhz RC clock oscillator and a 10Khz RC oscillator for a low power mode. And a UART, assorted timers, GPIO and such. Looks like a battery (or other power supply) and maybe a small power bypass cap and you are good to go. 

Looks like a great chip for things that could be cobbled together with a few lines of code and seemed so trivial that using a microprocessor chip seems overkill. (Although it will handle way more than just a few lines of code.)

Too bad it does not have a built in temperature sensor (I guess they have to leave something out for 24 cents). You could have used it to control your cooling fan and it might have been cheaper than a thermistor. I might make a dimmable red led light for the spotter scope graticule on my telescope. Hard to think of a much more trivial and previously though to be overkill project for a microprocessor. 

I ordered some for my parts box along with a $25 development board, with a built-in programmer, that looks like I can use to develop and program the chips with.

Hopefully there will be open source and manufacture supplied tools to develop and upload the programs, without needing expensive commercial development tools. I believe that is the case. It should be possible to cobble together a free toolchain if it does not already exist. If anyone else has done development with the various recent 8051 derivative chips, it would be interesting to hear about your thoughts. 

It will be fun to go back in time and visit to the good old days of very simple chips and instruction sets; but at the same time be modern.

I discovered this chip because I bought one of the WiFi relay modules on eBay and besides the WiFi module (ESP-01), this chip (actually the older version) was used to turn the relays on and off based on hex codes sent over a serial link.

I'll know more when everything arrives and can play with the development board.

Tom, wb6b

Tom, wb6b
 

On Thu, Mar 5, 2020 at 08:41 AM, Arv Evans wrote:
And they even have a dev board that looks a little like the Arduino Nano...
This is the dev board I purchased:
https://direct.nuvoton.com/en/nutiny-ms51fb9ae

It looks like you can snap the board in half, add a header to make a in-circuit programmer/debugger that you can use with your various projects, rather than just with the development board.

I've Googled around and found this complier:
http://sdcc.sourceforge.net
https://ftp.heanet.ie/mirrors/fosdem-video/2015/devroom-embedded/8bit_compiler.mp4

Now as long as there is a free driver and software for their programmer/debugger interface, things look good.

Maybe someone could port this to the Arduino platform. I wonder if the 8051 type processors would be able to run many of the libraries that make using the Arduino ecosystem so popular? None-the-less at least it would make the build/program process familiar. 

It could turn out using the above C complier and tools bundled with it, is simple enough for most folks to use it directly, rather than ported to the Arduino.

Amazingly, I've found the fact that SMDs pull themselves onto the correct position on the PC board pads, when the solder melts, makes them in some ways easier to use than through hole parts. Also, just using a lot of liquid flux and brushing your soldering iron tip across the pins of the SMD will usually suck up enough excess solder to clear any shorted pins. 

It took me a while to get used to the idea that you can bake (in actual toaster ovens), cook the whole SMD parts with heat guns (within limits) and such without damaging the parts. This is so much different than what I was used to about not overheating parts from days gone by. 

For some trivial projects, like the dimmable led, I might just bend every other pin away from each other and just solder everything together without a circuit board. (Maybe a little glue to hold the parts together.) Just to have the fun of being a minimalist.

I'll have to wait until everything arrives to know for sure.

Tom, wb6b

AC9NM - Jerry Ponko
 

If you get some low temperature solder paste (such as Maker Paste https://www.adafruit.com/product/3217 ) and a hobby/craft heat gun and most multi-pin surface mount parts shouldn't be a problem.  At $6.95 for a little tube, it may seem expensive but you'll be using tiny dabs of it with a pin. Another way to deal with them is to either buy or make some breakout to 8, 16 dip pcbs and you can then use 2.54mm pin sockets headers on your circuit boards.

Jerry, AC9NM

On 3/5/20 9:38 AM, Jack, W8TEE via Groups.Io wrte:
Mornin' Ken:

I agree with your statement, and that's really sad because most hams could easily do SMD parts. Farhan uses 1206 parts and even my 76 year old eyes and hands can work with them. They should invest $1.25 in an SMD practice kit (e.g., eBay 283799161850) and give it a try. I'll bet they would be surprised at how easy it is, plus kits using SMD parts are likely less expensive than a thru-hole equivalent.

Jack, W8TEE

On Thursday, March 5, 2020, 9:27:21 AM EST, Ken Hansen <ken@...> wrote:


Interesting, but from what I saw these are surface mount parts, many hams are put off by projects that rely on such parts.

Ken, N2VIP

On Mar 4, 2020, at 23:05, Tom, wb6b <wb6b@...> wrote:

Hi,

I stumbled upon these microprocessor chips at just $0.24 each. What is really compelling about these chips is they have an 8 channel A/D converter with 12 bit resolution. That is better than the Nano at 10 bits. And the A/D is many times faster.

Seems great where you would want to measure things in your radio, be able to digitize them and send the readings to other parts of the system, such as the Raduino. With a little bit of control functionally mixed in. 

https://direct.nuvoton.com/en/ms51fb9ae

Looks like the old time 8051 processors did not die, they still live on in inexpensive yet faster processor chips. I suppose there must be a warehouse of assembly code and possibility C code piled up on-line or elsewhere for these 8051 and derivative chips.

The chip has a built in factory trimmed 24mhz RC clock oscillator and a 10Khz RC oscillator for a low power mode. And a UART, assorted timers, GPIO and such. Looks like a battery (or other power supply) and maybe a small power bypass cap and you are good to go. 

Looks like a great chip for things that could be cobbled together with a few lines of code and seemed so trivial that using a microprocessor chip seems overkill. (Although it will handle way more than just a few lines of code.)

Too bad it does not have a built in temperature sensor (I guess they have to leave something out for 24 cents). You could have used it to control your cooling fan and it might have been cheaper than a thermistor. I might make a dimmable red led light for the spotter scope graticule on my telescope. Hard to think of a much more trivial and previously though to be overkill project for a microprocessor. 

I ordered some for my parts box along with a $25 development board, with a built-in programmer, that looks like I can use to develop and program the chips with.

Hopefully there will be open source and manufacture supplied tools to develop and upload the programs, without needing expensive commercial development tools. I believe that is the case. It should be possible to cobble together a free toolchain if it does not already exist. If anyone else has done development with the various recent 8051 derivative chips, it would be interesting to hear about your thoughts. 

It will be fun to go back in time and visit to the good old days of very simple chips and instruction sets; but at the same time be modern.

I discovered this chip because I bought one of the WiFi relay modules on eBay and besides the WiFi module (ESP-01), this chip (actually the older version) was used to turn the relays on and off based on hex codes sent over a serial link.

I'll know more when everything arrives and can play with the development board.

Tom, wb6b

--
Jack, W8TEE
-- 
Jerry AC9NM

Tom, wb6b
 

On Thu, Mar 5, 2020 at 10:19 AM, AC9NM - Jerry Ponko wrote:
low temperature solder paste
Wow, melts at only 140C. I may have to get some of that. Particularly if I start experimenting with some of the conductive inks that claim to be solderable. 

I definitely won't make any automotive projects, engine compartment or dashboard, projects with this solder paste. 

Tom, wb6b

AC9NM - Jerry Ponko
 

Yes, it works very well. If you do have solder bridges, just heat up a solder wick strip over the pins with a soldering iron will wick up the excess solder or using a fine tip soldering pencil just reheat and drag the excess solder away if it's just across two pins. You probable already use one, but nothing beats a temperature controlled soldering pencil with a fine point tip. I bought a Zeny ESD 937D+ on ebay for about $35 two years ago - works great. I used to be a Luddite when it came to soldering pencils/irons because I was out of the hobby electronics scene for a long time until I got my Amateur Extra class license in 2016 and started building stuff again and learned about soldering stations.

Jerry, AC9NM

On 3/5/20 1:19 PM, Tom, wb6b wrote:
On Thu, Mar 5, 2020 at 10:19 AM, AC9NM - Jerry Ponko wrote:
low temperature solder paste
Wow, melts at only 140C. I may have to get some of that. Particularly if I start experimenting with some of the conductive inks that claim to be solderable. 

I definitely won't make any automotive projects, engine compartment or dashboard, projects with this solder paste. 

Tom, wb6b
-- 
Jerry AC9NM

Wayne Leake
 

 RE soldering stations.
 I use a very old Weller station that uses different tips to change temp.
 Not sure how well that works, bit it has served me well for decades now.
 Same for my Weller soldering guns.
 I can do reasonably well with the soldering station by changing what tips I do have. Bought a few tips last year or before.
 But I hesitate to try soldering smd's as they are used today.
 I'm a bit on the old fashioned side, think 1970s mostly.
 Unlike the bulky irons I used in the 50s. Those can kill many of the parts we use now, though might be great for things that need more heat.
 I have one that my dad said was mine from way back, though the tip is not good looking, and I am not sure how good the power lead is.
 For now I'll stick with my soldering station, and guns for heavier soldering, like some coax connectors.

 Wayne WA2YNE



Richard Spohn
 

This brings up a point worth mentioning: beware of leaving your uBitx
-- or any other project with SMT boards -- in a hot vehicle in the
Summer months! -- Rich WB2GXM

On 3/5/20, Tom, wb6b <wb6b@...> wrote:
On Thu, Mar 5, 2020 at 10:19 AM, AC9NM - Jerry Ponko wrote:


low temperature solder paste
Wow, melts at only 140C. I may have to get some of that. Particularly if I
start experimenting with some of the conductive inks that claim to be
solderable.

I definitely won't make any automotive projects, engine compartment or
dashboard, projects with this solder paste.

Tom, wb6b



Bill Cromwell
 

Hi,

140 C is far past the boiling point of water. It does not get that hot in your car. Mighty uncomfortable. Maybe even lethal to living creatures. But water bottles I have always kept in my car *never* boiled. So temps below 100 C.

73,

Bill KU8H

On 3/5/20 4:12 PM, Richard Spohn wrote:
This brings up a point worth mentioning: beware of leaving your uBitx
-- or any other project with SMT boards -- in a hot vehicle in the
Summer months! -- Rich WB2GXM
On 3/5/20, Tom, wb6b <wb6b@...> wrote:
On Thu, Mar 5, 2020 at 10:19 AM, AC9NM - Jerry Ponko wrote:


low temperature solder paste
Wow, melts at only 140C. I may have to get some of that. Particularly if I
start experimenting with some of the conductive inks that claim to be
solderable.

I definitely won't make any automotive projects, engine compartment or
dashboard, projects with this solder paste.

Tom, wb6b



--
bark less - wag more

GM4CID
 

How about their NuMaker Uno (Arduino Compatible), details at 

https://direct.nuvoton.com/en/numaker-uno

Arduino IDE & Board Installation Guide

  1. Download and Install the Nu-Link USB Driver.
  2. Download Arduino IDE from https://www.arduino.cc/
  3. Run Arduino IDE installer to install it on PC.
  4. Run Arduino IDE.
    Go to File → Preferences, enter the following URL to textbox of ‘Additional Board Manager URLs’
    https://raw.githubusercontent.com/OpenNuvoton/NuMaker-UNO/master/package_nuvoton_index.json
  5. Arduino IDE : go to Tools → Board → Boards Manager
  6. NuMaker UNO will show up on the list, select NuMaker UNO and click install.
    After the package download is finished, go to Tools → Board and select NuMaker UNO to use it.

73, Bob GM4CID

Richard Spohn
 

My bad, mixed up C and F. Still not a good idea, IMHO. - Rich

On 3/5/20, Bill Cromwell <wrcromwell@...> wrote:
Hi,

140 C is far past the boiling point of water. It does not get that hot
in your car. Mighty uncomfortable. Maybe even lethal to living
creatures. But water bottles I have always kept in my car *never*
boiled. So temps below 100 C.

73,

Bill KU8H

On 3/5/20 4:12 PM, Richard Spohn wrote:
This brings up a point worth mentioning: beware of leaving your uBitx
-- or any other project with SMT boards -- in a hot vehicle in the
Summer months! -- Rich WB2GXM

On 3/5/20, Tom, wb6b <wb6b@...> wrote:
On Thu, Mar 5, 2020 at 10:19 AM, AC9NM - Jerry Ponko wrote:


low temperature solder paste
Wow, melts at only 140C. I may have to get some of that. Particularly if
I
start experimenting with some of the conductive inks that claim to be
solderable.

I definitely won't make any automotive projects, engine compartment or
dashboard, projects with this solder paste.

Tom, wb6b





--
bark less - wag more



Tom, wb6b
 

On Thu, Mar 5, 2020 at 02:59 PM, GM4CID wrote:
NuMaker Uno (Arduino Compatible),
That's cool. These look like 32 bit processor boards. The 24 cent processors are 8 bit. 

However, I'll check the prices of their 32 bit processors. May not be 24 cents but still might be good.

Tom, wb6b

Arv Evans
 

140C = 284F, so probably will not get that hot, even in an automobile setting in the sun.
_._


On Thu, Mar 5, 2020 at 2:12 PM Richard Spohn <wb2gxm@...> wrote:
This brings up a point worth mentioning:  beware of leaving your uBitx
-- or any other project with SMT boards -- in a hot vehicle in the
Summer months!  -- Rich WB2GXM

On 3/5/20, Tom, wb6b <wb6b@...> wrote:
> On Thu, Mar 5, 2020 at 10:19 AM, AC9NM - Jerry Ponko wrote:
>
>>
>> low temperature solder paste
>
> Wow, melts at only 140C. I may have to get some of that. Particularly if I
> start experimenting with some of the conductive inks that claim to be
> solderable.
>
> I definitely won't make any automotive projects, engine compartment or
> dashboard, projects with this solder paste.
>
> Tom, wb6b
>
>
>
>



Arv Evans
 

The NuMaker UNO also looks interesting.
_._


On Thu, Mar 5, 2020 at 3:37 PM GM4CID <gm4cid@...> wrote:
How about their NuMaker Uno (Arduino Compatible), details at 

https://direct.nuvoton.com/en/numaker-uno

Looks like Arduino IDE can be used.

73, Bob GM4CID

Tom, wb6b
 

On Thu, Mar 5, 2020 at 04:58 PM, Arv Evans wrote:
The NuMaker UNO also looks interesting.
Yes it does.

What is cool is that they include a second microprocessor on the board that works as a full in-circuit programmer and debugger. Something you have to buy separately for the Nano and most other Arduino boards. 

Here is something similar from ST with the same processor chip as the Blue Pills. It has a second chip programmed to be a built in STLink interface, the same thing as people buy separately in order to program their Blue Pill boards. ST has smaller Nano sized developer boards, also.

I believe I've seen 32 bit processor boards that claim they are Nano pinout compatible. Maybe that would be a way to upgrade the processor on the uBitx. But sprinkling in a few 24 cent processors to do additional tasks around the radio board could be a good way to go. Especially if they are doing simple tasks (like read a voltage, click a relay, supply an adjustable voltage for bias or a gain control circuit, control a fan, monitor SWR and such, under control of the main processor) that are not likely to need firmware upgrades. Leave the firmware upgrades to the main processor. 

https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-mpu-eval-tools/stm32-mcu-mpu-eval-tools/stm32-nucleo-boards/nucleo-f103rb.html

The Nuvoton board provides an Arduino IDE. There is Arduino IDE support for some of the ST developer boards, too.

The 32 bit chips are not in the ridiculously cheap 24 cent range, but they are under a couple of bucks, some under a buck. So not bad price wise. 

Tom, wb6b

Bill Cromwell
 

Hi,

I do recall a ham who hid his Icom 2AT two meter walkie under the driver seat in his car in high summer. He left it there for the entire work day. After he took it out from under that seat (very hot in the car). It started to work and after a second or two it quit. I replaced a transistor that had failed. At that time we all followed that practice. We decided when we removed the hidden radio (or had a mobile radio mounted in the car) we would wait for it to cool down a little *before* turning it on. I am sure hams with mobile radios in their cars do not consider that and have not mentioned it here before. Maybe this accounts for some mysterious radio failures.

That transistor may already have been on the edge right from the transistor manufacturer. In part specs there used to be two maximum part temperatures (are there still?). One was for temperature on the shelf (storage) and the other was for 'powered on'. The powered on was lower. Both were very high temps where we and our dogs would not survive but the radio would. Those parts do survive soldering. Use your best judgement. Waiting for a hot car to cool down a little is not a great imposition.

73,

Bill KU8H

On 3/5/20 7:28 PM, Richard Spohn wrote:
My bad, mixed up C and F. Still not a good idea, IMHO. - Rich
--
bark less - wag more

Tom, wb6b
 

On Fri, Mar 6, 2020 at 06:50 AM, Bill Cromwell wrote:
under the driver seat in his car in high summer
I melted a transistor radio (well the case and pooling wax) when I was a kid leaving it on the dashboard of a car on a summer day.  

While the 140C solder paste is above higher than likely to be found in a car, it is still significantly below that of "regular" solders. If there were any other heating sources during operation, there might be no safety margin.

I was curious just how hot you can get semiconductors. Found this article. Mentions using diodes at around 300C. Although you have to be willing to accept vasty shorter component lifetimes, apparently the parts may not instantly self destruct. 

http://www.extremetemperatureelectronics.com/tutorial1.html

Now I'm curious, maybe that is a project worthy of a 23 cent microprocessor. Slowly heat one up, while running a simple program, and see where it quits. 

I imagine things are different now days, when I was a teenager I would bring a thermos bottle (they did check that it was Pyrex) to an industrial gas supply company and they would fill it with liquid nitrogen for a dollar. Wonder if they would do that for a kid, or even an adult, at any cost now days. 

I lowered all kinds of parts and circuits into the liquid nitrogen to see how they worked at cold temperature.  

I used safety goggles, gloves and the other safety precautions they covered with me before letting me go my way with the bubbling thermos.

Tom, wb6b