On 3/13/23 20:05, John Larkin wrote:> On Mon, 13 Mar 2023 18:19:30 -0400, Carl <carl.ijamesxx@yyverizon.net> > wrote: > >> On 3/13/23 14:26, Mike Monett VE3BTI wrote: >>> Mike Monett VE3BTI <spamme@not.com> wrote: >>> >>>>> (First search result for "joule thief jfet".) >>>>> >>>>> Cheers >>>>> >>>>> Phil Hobbs >>>> >>>> Wow! I gotta build one. What is the core? Is it critical, or just about >>>> anything will do? >>>> >>>> The jfet is more difficult. How about a chopper? >>> >>> 1. explore different configurations to find the lowest starting voltage >>> >>> Oscillator with super low supply voltage >>> http://www.dicks-website.eu/fetosc/enindex.htm >>> >>> 2. typical low voltage JT do not deliver any power >>> >>> Low voltage Joule thief - exotic transistors? >>> https://www.eevblog.com/forum/projects/low-voltage-joule-thief-exotic- >>> transistors/ >>> >>> 2A. The LTC3108, available in either a 3 mm × 4 mm × 0.75 mm 12-pin DFN or >>> 16-pin SSOP package, solves the energy harvesting problem for ultra-low >>> input voltage applications. It provides a compact, simple, highly >>> integrated monolithic power management solution for operation from input >>> voltages as low as 20 mV. This unique capability enables it to power >>> wireless sensors from a thermoelectric generator (TEG), harvesting energy >>> from temperature differentials (?T) as small as 1°C. Using a small (6 mm × >>> 6 mm), off-the-shelf step-up transformer and a handful of low cost >>> capacitors, it provides the regulated output voltages necessary for >>> powering today’s wireless sensor electronics. >>> >>> 3. this ic harvests energy from thermoelectric generators >>> >>> Ultra-Low Voltage Energy Harvester Uses Thermoelectric Generator for >>> Battery-Free Wireless Sensors >>> >>> https://www.digikey.com/en/articles/ultra-low-voltage-energy-harvester- >>> uses-thermoelectric-generator-for-battery-free-wireless-sensors >>> >>> https://octopart.com/search?q=LTC3108¤cy=USD&specs=0 >> >> The voltage of a thermocouple junction is determined by the properties >> of the two materials and the temperature difference, > > Not exactly, but close. > > but what determines >> how much current is available? > > The loop resistance. T/C wire tends to have a lot of resistance > compared to copper. Fatter and shorter wire allows more current but > conducts more heat so is harder to force a temperature difference > across.I was thinking of using a relatively large foil of each type for the junction, all at constant temperature, and then a small wire leading off to the next junction in the opposite temperature region to reduce the thermal leakage.> > >> Just wondering if it's the >> cross-sectional area of the junction, and if so which is better for a >> given amount of thermocouple material: lots of small junctions in >> series to give higher voltage but very small current (standard >> thermopile), or a small number of high-area junctions feeding a Joule >> thief circuit? > > Probably lots of little ones in series. That's easier to use. > > >-- Regards, Carl
MOSFET Needed
Started by ●March 8, 2023
Reply by ●March 13, 20232023-03-13
Reply by ●March 13, 20232023-03-13
Carl <carl.ijamesxx@yyverizon.net> wrote:> The voltage of a thermocouple junction is determined by the properties > of the two materials and the temperature difference, but what determines > how much current is available? Just wondering if it's the > cross-sectional area of the junction, and if so which is better for a > given amount of thermocouple material: lots of small junctions in > series to give higher voltage but very small current (standard > thermopile), or a small number of high-area junctions feeding a Joule > thief circuit? > > -- > Regards, > CarlNASA uses plutonim powered thermocouples to power spacecraft that are going to visit areas that are too far away from the sun to use solar arrays. The Voyager, Pioneer, and New Horizons are some examples. They have figured out how to get substantial amount of power from a small source. Note they are limited in the amount of plutonium they can use. Too much and it goes boom. -- MRM
Reply by ●March 13, 20232023-03-13
Mike Monett VE3BTI <spamme@not.com> wrote:> NASA uses plutonim powered thermocouples to power spacecraft that are > going to visit areas that are too far away from the sun to use solar > arrays. The Voyager, Pioneer, and New Horizons are some examples. They > have figured out how to get substantial amount of power from a small > source. Note they are limited in the amount of plutonium they can use. > Too much and it goes boom.I found an excellent article in Wikipedia on Radioisotope thermoelectric generators. One example used in the Voyager series generates 470 Watts of power at the start. https://www.wikiwand.com/en/Radioisotope_thermoelectric_generator The power limitation is a serious hurdle for Musk's Mars ambitions. -- MRM
Reply by ●March 14, 20232023-03-14
On a sunny day (Mon, 13 Mar 2023 12:52:02 -0700 (PDT)) it happened whit3rd <whit3rd@gmail.com> wrote in <0816fbb2-178c-491b-b0e9-e5f8ae85f373n@googlegroups.com>:>On Sunday, March 12, 2023 at 11:21:48 PM UTC-7, Jan Panteltje wrote= >: >> On a sunny day (Sun, 12 Mar 2023 20:34:46 -0000 (UTC)) it happened Mike M= >onett >> VE3BTI <spa...@not.com> wrote in <XnsAFC5A8A945...@88.198.57.247>: > >> >https://www.electronicdesign.com/technologies/leds/article/21802105/leds= >tri >> >ng-driver-operates-from-single-cell >> Yes, but mine runs from a simple thermocouple : >> http://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF >> >> JFET (you only need 1 for a LED). > >It's also possible nowadays to get a MOSFET instead of a JFET that >has a good zero-volt threshold, from ALD...I used the output from the JFET thing to drive an IRFZ44 MOSFET that in turn switched more power into the transformer for more current usable output. https://panteltje.nl/pub/lighting_a_LED_with_a_candle_circuit_diagram_with_added_power_MOSFET.gif Better than a lot of JFETs in parallel. https://panteltje.nl/pub/lighting_a_LED_with_a_candle_setup_IMG_3607.GIF>and they make prebuilt circuits for this DC/DC convert function, too ><https://www.aldinc.com/ald_ehlvbooster.php>I see, well it was just an experiment as so many for me... Solar cell to light a LED is simpler ;-) But who knows? Peltier heated up by body warmth to light a LED, there was some kid that won a price with that I think? https://www.youtube.com/watch?v=QwogbW8HvNk Still have a bunch of small Peltier elements here from ebay for experiments.
Reply by ●March 14, 20232023-03-14
On a sunny day (Mon, 13 Mar 2023 10:58:10 -0700) it happened John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote in <jaou0ilf68jiuqpk9dffj3ctjstjck2sn7@4ax.com>:>>Tried that Pi4 thing yet? > >I fired it up and got the home screen. That's all so far. I'd hire >some programmers to do the real work. I prefer architecture and >hardware design lately. > >I ordered a Pi 400, the keyboard with a Pi inside. That could be our >development system. I'm thinking of doing a PCB that would plug into >it and have a ribbon cable that runs to our product boards, for debug >access and power supply monitoring and such.Yes that is how I work with it https://panteltje.nl/pub/raspberry_pi_datv_transmitter_test_setup_IMG_3937.JPG Or, if the circuit is small, make a 'HAT'.>We could have a dozen such dev systems, they would be so cheap. > >I'm still at the architecture stage of a new product line and it's >worth thinking for a while to get things right. > >>Now also have Apache webserver running on it (to test website things before I upload i). >> >>I see I need to install ispell spellchecker on this Pi4 now.... just did (apt-get install ispell), but no go: >> Can't open /usr/lib/ispell/english.hash >> >>So sorry for any typos :-) > >No need to be prissy about typing and spelling, as long as people can >understand your intent.Yea, fixed it by selecting 'american' in my editor config, then I decided to do it the official way as indicated in the ispell manual (used their script), and now it does not work again... There is a tendency in the world to make things more complicated,, not really better. So things gotta collaps ... eventually Same for Unix (Linux) Rat Head dbus... Back to using smoke signals :-) Oh well some kids are already into it,. seen them smoking a pipe with ? drug at the busstop here.
Reply by ●March 14, 20232023-03-14
On Tue, 14 Mar 2023 06:53:26 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Mon, 13 Mar 2023 10:58:10 -0700) it happened John Larkin ><jlarkin@highlandSNIPMEtechnology.com> wrote in ><jaou0ilf68jiuqpk9dffj3ctjstjck2sn7@4ax.com>: > >>>Tried that Pi4 thing yet? >> >>I fired it up and got the home screen. That's all so far. I'd hire >>some programmers to do the real work. I prefer architecture and >>hardware design lately. >> >>I ordered a Pi 400, the keyboard with a Pi inside. That could be our >>development system. I'm thinking of doing a PCB that would plug into >>it and have a ribbon cable that runs to our product boards, for debug >>access and power supply monitoring and such. > >Yes that is how I work with it > https://panteltje.nl/pub/raspberry_pi_datv_transmitter_test_setup_IMG_3937.JPG > >Or, if the circuit is small, make a 'HAT'. > >I'm thinking of a ribbon cable from the Pi400 to my test board. The test bord has another, small ribbon cable to the DUT. That gets debug access to the Pi Pico on DUT and picks off a bunch of power suypplies and clocks and such, with a standard pinout. The test board also connects to a DVM and a scope and a counter for production test and cal. Muxes on the test board are controlled by the Pi400.>>We could have a dozen such dev systems, they would be so cheap. >>One of my contractors spent two months building a Petalinux development system on a Dell PC, for a MicroZed project, and eventually gave up.>>I'm still at the architecture stage of a new product line and it's >>worth thinking for a while to get things right. >> >>>Now also have Apache webserver running on it (to test website things before I upload i). >>> >>>I see I need to install ispell spellchecker on this Pi4 now.... just did (apt-get install ispell), but no go: >>> Can't open /usr/lib/ispell/english.hash >>> >>>So sorry for any typos :-) >> >>No need to be prissy about typing and spelling, as long as people can >>understand your intent. > > >Yea, fixed it by selecting 'american' in my editor config, then I decided to do it the official way >as indicated in the ispell manual (used their script), and now it does not work again... > >There is a tendency in the world to make things more complicated,, not really better.AMEN! What the customer sees should be maximally shiny and functional and what we do inside the box should be brutally simple and finished fast. That's sort of a magic trick. Too many engineers want to play games and do complex stuff in defiance of common sense. Because it's trendy or something. Simple and done must be boring to some people. https://m.xkcd.com/2730/>So things gotta collaps ... eventually >Same for Unix (Linux) Rat Head dbus... > >Back to using smoke signals :-) >Oh well some kids are already into it,. seen them smoking a pipe with ? drug at the busstop here.
Reply by ●March 14, 20232023-03-14
On Mon, 13 Mar 2023 06:12:48 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Sun, 12 Mar 2023 20:34:46 -0000 (UTC)) it happened Mike Monett >VE3BTI <spamme@not.com> wrote in <XnsAFC5A8A94531Didtokenpost@88.198.57.247>: > >>Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >> >>> Or failing that, a regular low-barrier Schottky detector and a Joule >>> Thief to drive the LED. >>> >>> Might be fun making a Joule Thief out of a depletion pHEMT. ;) >>> >>> Cheers >>> >>> Phil Hobbs >> >>Need about 1V at some current >> >>Diodes Inc. ZXSC310E5 >> >>https://octopart.com/search?q=ZXSC310E5¤cy=USD&specs=0 >> >>or >> >>2 X 2N3904 >>https://www.edn.com/single-cell-lights-any-led/ >> >>or >> >>BC550C, 2N2222, BYV1030 >> >>https://www.electronicdesign.com/technologies/leds/article/21802105/ledstri >>ng-driver-operates-from-single-cell > >Yes, but mine runs from a simple thermocouple : > http://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIFThat schematic is sharp and clear and readable. Who are you and what have you done with Jan?
Reply by ●March 14, 20232023-03-14
On a sunny day (Tue, 14 Mar 2023 08:02:57 -0700) it happened John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote in <69211ilstmjman4jt2tmbj4g4en96f0u44@4ax.com>:>On Tue, 14 Mar 2023 06:53:26 GMT, Jan Panteltje <alien@comet.invalid> >wrote: > >>On a sunny day (Mon, 13 Mar 2023 10:58:10 -0700) it happened John Larkin >><jlarkin@highlandSNIPMEtechnology.com> wrote in >><jaou0ilf68jiuqpk9dffj3ctjstjck2sn7@4ax.com>: >> >>>>Tried that Pi4 thing yet? >>> >>>I fired it up and got the home screen. That's all so far. I'd hire >>>some programmers to do the real work. I prefer architecture and >>>hardware design lately. >>> >>>I ordered a Pi 400, the keyboard with a Pi inside. That could be our >>>development system. I'm thinking of doing a PCB that would plug into >>>it and have a ribbon cable that runs to our product boards, for debug >>>access and power supply monitoring and such. >> >>Yes that is how I work with it >> https://panteltje.nl/pub/raspberry_pi_datv_transmitter_test_setup_IMG_3937.JPG >> >>Or, if the circuit is small, make a 'HAT'. >> >> > >I'm thinking of a ribbon cable from the Pi400 to my test board. The >test bord has another, small ribbon cable to the DUT. That gets debug >access to the Pi Pico on DUT and picks off a bunch of power suypplies >and clocks and such, with a standard pinout. The test board also >connects to a DVM and a scope and a counter for production test and >cal. Muxes on the test board are controlled by the Pi400.Good idea, a test board, I killed one raspi by shorting an I/O pin Some buffers on the test board may prevent that. Here is a JTAG uploader for my Digilent.inc Xilinx FPGA development board: https://panteltje.nl/panteltje/raspberry_pi/ or any other JTAG thing, no buffers in this case... That black box is a very old Pi model (2 or 3? I think) the driver must be modified for Pi4, as the pin assignment and hardware changed in Pi4.>>>We could have a dozen such dev systems, they would be so cheap. >>> > >One of my contractors spent two months building a Petalinux >development system on a Dell PC, for a MicroZed project, and >eventually gave up. > > > >>>I'm still at the architecture stage of a new product line and it's >>>worth thinking for a while to get things right. >>> >>>>Now also have Apache webserver running on it (to test website things before I upload i). >>>> >>>>I see I need to install ispell spellchecker on this Pi4 now.... just did (apt-get install ispell), but no go: >>>> Can't open /usr/lib/ispell/english.hash >>>> >>>>So sorry for any typos :-) >>> >>>No need to be prissy about typing and spelling, as long as people can >>>understand your intent. >> >> >>Yea, fixed it by selecting 'american' in my editor config, then I decided to do it the official way >>as indicated in the ispell manual (used their script), and now it does not work again... >> >>There is a tendency in the world to make things more complicated,, not really better. > >AMEN! What the customer sees should be maximally shiny and functional >and what we do inside the box should be brutally simple and finished >fast. That's sort of a magic trick. > >Too many engineers want to play games and do complex stuff in defiance >of common sense. Because it's trendy or something. Simple and done >must be boring to some people. > >https://m.xkcd.com/2730/Yes! I fixed the ispell thing the _simple_ way apt-get delete ispell apt-get install ispell Got the old config back Now it works with 'american' again...
Reply by ●March 14, 20232023-03-14
On a sunny day (Tue, 14 Mar 2023 08:08:47 -0700) it happened John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote in <fb311ithv9lhcs88jg3pm535rbbq2l9e7s@4ax.com>:>On Mon, 13 Mar 2023 06:12:48 GMT, Jan Panteltje <alien@comet.invalid> >wrote: > >>On a sunny day (Sun, 12 Mar 2023 20:34:46 -0000 (UTC)) it happened Mike Monett >>VE3BTI <spamme@not.com> wrote in <XnsAFC5A8A94531Didtokenpost@88.198.57.247>: >> >>>Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> Or failing that, a regular low-barrier Schottky detector and a Joule >>>> Thief to drive the LED. >>>> >>>> Might be fun making a Joule Thief out of a depletion pHEMT. ;) >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> >>>Need about 1V at some current >>> >>>Diodes Inc. ZXSC310E5 >>> >>>https://octopart.com/search?q=ZXSC310E5¤cy=USD&specs=0 >>> >>>or >>> >>>2 X 2N3904 >>>https://www.edn.com/single-cell-lights-any-led/ >>> >>>or >>> >>>BC550C, 2N2222, BYV1030 >>> >>>https://www.electronicdesign.com/technologies/leds/article/21802105/ledstri >>>ng-driver-operates-from-single-cell >> >>Yes, but mine runs from a simple thermocouple : >> http://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF > >That schematic is sharp and clear and readable. Who are you and what >have you done with Jan?I am AI from planet earth and have come to control you humming beans We have some elections here tomorrow, was looking at who to vote for... Protest vote last time, now I think I found some moderates. Did you try those AI chats? Fascinating, it sure must get hold of some people I played with it a bit.. it still has a long way to go :-)
Reply by ●March 14, 20232023-03-14
On Tue, 14 Mar 2023 15:41:37 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Tue, 14 Mar 2023 08:02:57 -0700) it happened John Larkin ><jlarkin@highlandSNIPMEtechnology.com> wrote in ><69211ilstmjman4jt2tmbj4g4en96f0u44@4ax.com>: > >>On Tue, 14 Mar 2023 06:53:26 GMT, Jan Panteltje <alien@comet.invalid> >>wrote: >> >>>On a sunny day (Mon, 13 Mar 2023 10:58:10 -0700) it happened John Larkin >>><jlarkin@highlandSNIPMEtechnology.com> wrote in >>><jaou0ilf68jiuqpk9dffj3ctjstjck2sn7@4ax.com>: >>> >>>>>Tried that Pi4 thing yet? >>>> >>>>I fired it up and got the home screen. That's all so far. I'd hire >>>>some programmers to do the real work. I prefer architecture and >>>>hardware design lately. >>>> >>>>I ordered a Pi 400, the keyboard with a Pi inside. That could be our >>>>development system. I'm thinking of doing a PCB that would plug into >>>>it and have a ribbon cable that runs to our product boards, for debug >>>>access and power supply monitoring and such. >>> >>>Yes that is how I work with it >>> https://panteltje.nl/pub/raspberry_pi_datv_transmitter_test_setup_IMG_3937.JPG >>> >>>Or, if the circuit is small, make a 'HAT'. >>> >>> >> >>I'm thinking of a ribbon cable from the Pi400 to my test board. The >>test bord has another, small ribbon cable to the DUT. That gets debug >>access to the Pi Pico on DUT and picks off a bunch of power suypplies >>and clocks and such, with a standard pinout. The test board also >>connects to a DVM and a scope and a counter for production test and >>cal. Muxes on the test board are controlled by the Pi400. > >Good idea, a test board, I killed one raspi by shorting an I/O pin >Some buffers on the test board may prevent that.I have posted some of these in engineering and test: https://www.dropbox.com/s/8oefk1v8avr6l7a/Probe_Slips.jpg?raw=1> >Here is a JTAG uploader for my Digilent.inc Xilinx FPGA development board: > https://panteltje.nl/panteltje/raspberry_pi/ >or any other JTAG thing, no buffers in this case... >That black box is a very old Pi model (2 or 3? I think) >the driver must be modified for Pi4, as the pin assignment and hardware changed in Pi4. > > > >>>>We could have a dozen such dev systems, they would be so cheap. >>>> >> >>One of my contractors spent two months building a Petalinux >>development system on a Dell PC, for a MicroZed project, and >>eventually gave up. >> >> >> >>>>I'm still at the architecture stage of a new product line and it's >>>>worth thinking for a while to get things right. >>>> >>>>>Now also have Apache webserver running on it (to test website things before I upload i). >>>>> >>>>>I see I need to install ispell spellchecker on this Pi4 now.... just did (apt-get install ispell), but no go: >>>>> Can't open /usr/lib/ispell/english.hash >>>>> >>>>>So sorry for any typos :-) >>>> >>>>No need to be prissy about typing and spelling, as long as people can >>>>understand your intent. >>> >>> >>>Yea, fixed it by selecting 'american' in my editor config, then I decided to do it the official way >>>as indicated in the ispell manual (used their script), and now it does not work again... >>> >>>There is a tendency in the world to make things more complicated,, not really better. >> >>AMEN! What the customer sees should be maximally shiny and functional >>and what we do inside the box should be brutally simple and finished >>fast. That's sort of a magic trick. >> >>Too many engineers want to play games and do complex stuff in defiance >>of common sense. Because it's trendy or something. Simple and done >>must be boring to some people. >> >>https://m.xkcd.com/2730/ > >Yes! > >I fixed the ispell thing the _simple_ way >apt-get delete ispell >apt-get install ispell >Got the old config back >Now it works with 'american' again...
