On Sat, 11 Mar 2023 16:45:50 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Sat, 11 Mar 2023 08:23:45 -0800) it happened John Larkin ><jlarkin@highlandSNIPMEtechnology.com> wrote in ><kcap0i9kf0tuc35hnlirtoobkqj6u19fgu@4ax.com>: > >>We do have an all-facility EMI test system: >> >>https://www.dropbox.com/s/tmcpmvqp714c82o/Roof_West.JPG?raw=1 > >? >All I see is a roof with some boxes? >Or are you referring to that antenna tower?Yes. Sutro Tower. I suspect that the bowl of Castro Valley focusses the RF into our building. I have been meaning to use the field to light up some LEDs.>I remember a discussion about that here some time ago. >I have a similar source of RF power here, the radar station just a few km from here. > https://panteltje.nl/pub/radar_2kHz_spectrum_burst.gif >it works at about 1.35 GHz but sweeps over a wide band. >Signal is VERY strong and interferes with satellite reception on some channels >as the 1.35 GHz is in the middle of the signal from the LNB down converter.
MOSFET Needed
Started by ●March 8, 2023
Reply by ●March 11, 20232023-03-11
Reply by ●March 12, 20232023-03-12
On a sunny day (Sat, 11 Mar 2023 10:08:57 -0800) it happened John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote in <aegp0i55pmr0sggm9udi28i91b2pa9gao3@4ax.com>:>On Sat, 11 Mar 2023 16:45:50 GMT, Jan Panteltje <alien@comet.invalid> >wrote: > >>On a sunny day (Sat, 11 Mar 2023 08:23:45 -0800) it happened John Larkin >><jlarkin@highlandSNIPMEtechnology.com> wrote in >><kcap0i9kf0tuc35hnlirtoobkqj6u19fgu@4ax.com>: >> >>>We do have an all-facility EMI test system: >>> >>>https://www.dropbox.com/s/tmcpmvqp714c82o/Roof_West.JPG?raw=1 >> >>? >>All I see is a roof with some boxes? >>Or are you referring to that antenna tower? > >Yes. Sutro Tower. I suspect that the bowl of Castro Valley focusses >the RF into our building. I have been meaning to use the field to >light up some LEDs.Yes, nice idea Now I think about the radar making a flashing LED, It is a rotating thing, every few seconds the beam hits here and some SAT channels get affected. So a microwave antenna with high voltage output, and/or diode followed by a low voltage up-converter, like this from a thermocouple: https://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF Or maybe better for this purpose? BAT diode voltage multiplier chain: https://panteltje.nl/pub/bat15-99.gif Or dish antenna? Bit big... For lower frequencies just a few meters of wire may work (wavelength related). So light your house with power from that tower Was reading once about a guy who took power from the overhead powerlines by running a long wire in parallel under it.. He was sued for stealing power IIRC. Pretty cool idea though, if you have the land.>>I remember a discussion about that here some time ago. >>I have a similar source of RF power here, the radar station just a few km from here. >> https://panteltje.nl/pub/radar_2kHz_spectrum_burst.gif >>it works at about 1.35 GHz but sweeps over a wide band. >>Signal is VERY strong and interferes with satellite reception on some channels >>as the 1.35 GHz is in the middle of the signal from the LNB down converter. >
Reply by ●March 12, 20232023-03-12
On Sun, 12 Mar 2023 06:24:06 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Sat, 11 Mar 2023 10:08:57 -0800) it happened John Larkin ><jlarkin@highlandSNIPMEtechnology.com> wrote in ><aegp0i55pmr0sggm9udi28i91b2pa9gao3@4ax.com>: > >>On Sat, 11 Mar 2023 16:45:50 GMT, Jan Panteltje <alien@comet.invalid> >>wrote: >> >>>On a sunny day (Sat, 11 Mar 2023 08:23:45 -0800) it happened John Larkin >>><jlarkin@highlandSNIPMEtechnology.com> wrote in >>><kcap0i9kf0tuc35hnlirtoobkqj6u19fgu@4ax.com>: >>> >>>>We do have an all-facility EMI test system: >>>> >>>>https://www.dropbox.com/s/tmcpmvqp714c82o/Roof_West.JPG?raw=1 >>> >>>? >>>All I see is a roof with some boxes? >>>Or are you referring to that antenna tower? >> >>Yes. Sutro Tower. I suspect that the bowl of Castro Valley focusses >>the RF into our building. I have been meaning to use the field to >>light up some LEDs. > >Yes, nice idea >Now I think about the radar making a flashing LED, >It is a rotating thing, every few seconds the beam hits here and some SAT channels get affected. > >So a microwave antenna with high voltage output, and/or diode followed by a low voltage up-converter, >like this from a thermocouple: > https://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF > >Or maybe better for this purpose? >BAT diode voltage multiplier chain: > https://panteltje.nl/pub/bat15-99.gif > >Or dish antenna? Bit big... > > >For lower frequencies just a few meters of wire may work (wavelength related). >So light your house with power from that towerThese people might. I've been told that all sorts of things go wrong on that street. https://www.dropbox.com/s/4fzsmipz0rar4ke/Panoramic_Drive.jpg?raw=1 The speakers on my ratty old Fiesta would buzz when I drove there, with the radio turned off.>Was reading once about a guy who took power from the overhead powerlines by running a long >wire in parallel under it.. >He was sued for stealing power IIRC. >Pretty cool idea though, if you have the land. > >I'm thinking that a resonated loop antenna might make enough voltage to light an LED; a good LED is visible at a few uA. Maybe have the LED capacitance be part of the resonance, or rectify with a low-barrier Schottky. Some LEDs are fast and have low capacitance, some aren't.> >>>I remember a discussion about that here some time ago. >>>I have a similar source of RF power here, the radar station just a few km from here. >>> https://panteltje.nl/pub/radar_2kHz_spectrum_burst.gif >>>it works at about 1.35 GHz but sweeps over a wide band. >>>Signal is VERY strong and interferes with satellite reception on some channels >>>as the 1.35 GHz is in the middle of the signal from the LNB down converter. >>
Reply by ●March 12, 20232023-03-12
On a sunny day (Sun, 12 Mar 2023 08:39:08 -0700) it happened John Larkin <jlarkin@highlandSNIPMEtechnology.com> wrote in <b1sr0ih1h89avbdndvannrbcvjta3nd5ot@4ax.com>:>On Sun, 12 Mar 2023 06:24:06 GMT, Jan Panteltje <alien@comet.invalid> >wrote: > >>On a sunny day (Sat, 11 Mar 2023 10:08:57 -0800) it happened John Larkin >><jlarkin@highlandSNIPMEtechnology.com> wrote in >><aegp0i55pmr0sggm9udi28i91b2pa9gao3@4ax.com>: >> >>>On Sat, 11 Mar 2023 16:45:50 GMT, Jan Panteltje <alien@comet.invalid> >>>wrote: >>> >>>>On a sunny day (Sat, 11 Mar 2023 08:23:45 -0800) it happened John Larkin >>>><jlarkin@highlandSNIPMEtechnology.com> wrote in >>>><kcap0i9kf0tuc35hnlirtoobkqj6u19fgu@4ax.com>: >>>> >>>>>We do have an all-facility EMI test system: >>>>> >>>>>https://www.dropbox.com/s/tmcpmvqp714c82o/Roof_West.JPG?raw=1 >>>> >>>>? >>>>All I see is a roof with some boxes? >>>>Or are you referring to that antenna tower? >>> >>>Yes. Sutro Tower. I suspect that the bowl of Castro Valley focusses >>>the RF into our building. I have been meaning to use the field to >>>light up some LEDs. >> >>Yes, nice idea >>Now I think about the radar making a flashing LED, >>It is a rotating thing, every few seconds the beam hits here and some SAT channels get affected. >> >>So a microwave antenna with high voltage output, and/or diode followed by a low voltage up-converter, >>like this from a thermocouple: >> https://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF >> >>Or maybe better for this purpose? >>BAT diode voltage multiplier chain: >> https://panteltje.nl/pub/bat15-99.gif >> >>Or dish antenna? Bit big... >> >> >>For lower frequencies just a few meters of wire may work (wavelength related). >>So light your house with power from that tower > >These people might. I've been told that all sorts of things go wrong >on that street. > >https://www.dropbox.com/s/4fzsmipz0rar4ke/Panoramic_Drive.jpg?raw=1Very typical houses, likly related to the slope of the hill>The speakers on my ratty old Fiesta would buzz when I drove there, >with the radio turned off. > > >>Was reading once about a guy who took power from the overhead powerlines by running a long >>wire in parallel under it.. >>He was sued for stealing power IIRC. >>Pretty cool idea though, if you have the land. >> >> > >I'm thinking that a resonated loop antenna might make enough voltage >to light an LED; a good LED is visible at a few uA. Maybe have the LED >capacitance be part of the resonance, or rectify with a low-barrier >Schottky. Some LEDs are fast and have low capacitance, some aren't.Yes, e LED parallel to a tuned LC might work.... Using an Extra diode would drop some voltage.. ------------------ | |Cv |k |a L =/= LED1 LED2 | | |a |k ------------------ tuning cap In my school days I build a 250 W linear, anttenna wire in the garden from the house towards a tree. A neon bulb would light when anywhere near that antenna when transmitting! About 7 MHz.. shortwave ham band No license back then, got almost caught.. Almost ;-)
Reply by ●March 12, 20232023-03-12
On Sunday, March 12, 2023 at 11:39:23 AM UTC-4, John Larkin wrote:> On Sun, 12 Mar 2023 06:24:06 GMT, Jan Panteltje <al...@comet.invalid> > wrote: > > >On a sunny day (Sat, 11 Mar 2023 10:08:57 -0800) it happened John Larkin > ><jla...@highlandSNIPMEtechnology.com> wrote in > ><aegp0i55pmr0sggm9...@4ax.com>: > > > >>On Sat, 11 Mar 2023 16:45:50 GMT, Jan Panteltje <al...@comet.invalid> > >>wrote: > >> > >>>On a sunny day (Sat, 11 Mar 2023 08:23:45 -0800) it happened John Larkin > >>><jla...@highlandSNIPMEtechnology.com> wrote in > >>><kcap0i9kf0tuc35hn...@4ax.com>: > >>> > >>>>We do have an all-facility EMI test system: > >>>> > >>>>https://www.dropbox.com/s/tmcpmvqp714c82o/Roof_West.JPG?raw=1 > >>> > >>>? > >>>All I see is a roof with some boxes? > >>>Or are you referring to that antenna tower? > >> > >>Yes. Sutro Tower. I suspect that the bowl of Castro Valley focusses > >>the RF into our building. I have been meaning to use the field to > >>light up some LEDs. > > > >Yes, nice idea > >Now I think about the radar making a flashing LED, > >It is a rotating thing, every few seconds the beam hits here and some SAT channels get affected. > > > >So a microwave antenna with high voltage output, and/or diode followed by a low voltage up-converter, > >like this from a thermocouple: > > https://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF > > > >Or maybe better for this purpose? > >BAT diode voltage multiplier chain: > > https://panteltje.nl/pub/bat15-99.gif > > > >Or dish antenna? Bit big... > > > > > >For lower frequencies just a few meters of wire may work (wavelength related). > >So light your house with power from that tower > These people might. I've been told that all sorts of things go wrong > on that street. > > https://www.dropbox.com/s/4fzsmipz0rar4ke/Panoramic_Drive.jpg?raw=1 > > The speakers on my ratty old Fiesta would buzz when I drove there, > with the radio turned off. > >Was reading once about a guy who took power from the overhead powerlines by running a long > >wire in parallel under it.. > >He was sued for stealing power IIRC. > >Pretty cool idea though, if you have the land. > > > > > I'm thinking that a resonated loop antenna might make enough voltage > to light an LED; a good LED is visible at a few uA. Maybe have the LED > capacitance be part of the resonance, or rectify with a low-barrier > Schottky. Some LEDs are fast and have low capacitance, some aren't.I've done the math for a 60 kHz loop, 50 ft diameter. Nowhere near enough power. It's not enough to ask for voltage. Without power you just drag down the Q of the antenna. I suppose if you are talking about being "visible" in a dark room staring directly at the LED, you might be able to get enough power, but nothing useful. -- Rick C. - Get 1,000 miles of free Supercharging - Tesla referral code - https://ts.la/richard11209
Reply by ●March 12, 20232023-03-12
On 2023-03-12 12:50, Jan Panteltje wrote:> On a sunny day (Sun, 12 Mar 2023 08:39:08 -0700) it happened John Larkin > <jlarkin@highlandSNIPMEtechnology.com> wrote in > <b1sr0ih1h89avbdndvannrbcvjta3nd5ot@4ax.com>: > >> On Sun, 12 Mar 2023 06:24:06 GMT, Jan Panteltje <alien@comet.invalid> >> wrote: >> >>> On a sunny day (Sat, 11 Mar 2023 10:08:57 -0800) it happened John Larkin >>> <jlarkin@highlandSNIPMEtechnology.com> wrote in >>> <aegp0i55pmr0sggm9udi28i91b2pa9gao3@4ax.com>: >>> >>>> On Sat, 11 Mar 2023 16:45:50 GMT, Jan Panteltje <alien@comet.invalid> >>>> wrote: >>>> >>>>> On a sunny day (Sat, 11 Mar 2023 08:23:45 -0800) it happened John Larkin >>>>> <jlarkin@highlandSNIPMEtechnology.com> wrote in >>>>> <kcap0i9kf0tuc35hnlirtoobkqj6u19fgu@4ax.com>: >>>>> >>>>>> We do have an all-facility EMI test system: >>>>>> >>>>>> https://www.dropbox.com/s/tmcpmvqp714c82o/Roof_West.JPG?raw=1 >>>>> >>>>> ? >>>>> All I see is a roof with some boxes? >>>>> Or are you referring to that antenna tower? >>>> >>>> Yes. Sutro Tower. I suspect that the bowl of Castro Valley focusses >>>> the RF into our building. I have been meaning to use the field to >>>> light up some LEDs. >>> >>> Yes, nice idea >>> Now I think about the radar making a flashing LED, >>> It is a rotating thing, every few seconds the beam hits here and some SAT channels get affected. >>> >>> So a microwave antenna with high voltage output, and/or diode followed by a low voltage up-converter, >>> like this from a thermocouple: >>> https://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF >>> >>> Or maybe better for this purpose? >>> BAT diode voltage multiplier chain: >>> https://panteltje.nl/pub/bat15-99.gif >>> >>> Or dish antenna? Bit big... >>> >>> >>> For lower frequencies just a few meters of wire may work (wavelength related). >>> So light your house with power from that tower >> >> These people might. I've been told that all sorts of things go wrong >> on that street. >> >> https://www.dropbox.com/s/4fzsmipz0rar4ke/Panoramic_Drive.jpg?raw=1 > > Very typical houses, likly related to the slope of the hill > > >> The speakers on my ratty old Fiesta would buzz when I drove there, >> with the radio turned off. >> >> >>> Was reading once about a guy who took power from the overhead powerlines by running a long >>> wire in parallel under it.. >>> He was sued for stealing power IIRC. >>> Pretty cool idea though, if you have the land. >>> >>> >> >> I'm thinking that a resonated loop antenna might make enough voltage >> to light an LED; a good LED is visible at a few uA. Maybe have the LED >> capacitance be part of the resonance, or rectify with a low-barrier >> Schottky. Some LEDs are fast and have low capacitance, some aren't. > > Yes, e LED parallel to a tuned LC might work.... > Using an Extra diode would drop some voltage.. > ------------------ > | |Cv |k |a > L =/= LED1 LED2 > | | |a |k > ------------------ > tuning > cap > > In my school days I build a 250 W linear, anttenna wire in the garden from the house towards a tree. > A neon bulb would light when anywhere near that antenna when transmitting! > About 7 MHz.. shortwave ham band > No license back then, got almost caught.. > Almost ;-) > > >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 -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●March 12, 20232023-03-12
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 HobbsNeed 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 -- MRM
Reply by ●March 12, 20232023-03-12
On 2023-03-12 16:34, Mike Monett VE3BTI wrote:> 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 > > > >A Joule Thief will start up and run from less than 100 mV. It does need magnetics, e.g. <https://rustybolt.info/wordpress/?p=10944> (First search result for "joule thief jfet".) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●March 12, 20232023-03-12
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:> A Joule Thief will start up and run from less than 100 mV. It does need > magnetics, e.g. > > <https://rustybolt.info/wordpress/?p=10944> > > (First search result for "joule thief jfet".) > > Cheers > > Phil HobbsWow! 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? J111 Series N-Channel 35 V 20 mA Through Hole JFET Chopper Transistor - TO- 92-3 https://octopart.com/search?q=J111-D26Z¤cy=USD&specs=0 - not as sharp cutoff tho https://octopart.com/search?q=2sk170¤cy=USD&specs=0 -- MRM
Reply by ●March 13, 20232023-03-13
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-cellYes, 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). In the case of John Larkin's radio tower we need to know the frequency. In this circuit you can get a lot of voltage gain like this: \ / antenna | | tunable core | --------------- | || | | | | || ( |a |k ) || ( LED1 LED2 | || ( |k |a | | | | |-------------------- | /// GND Basically the normal antique antenna circuit, Slide in a ferroxcube rod and you can tune it with that if it is AM medium wave, no antenna needed. LEDs also work great on higher frequencies, I had a LED on my GPA 27 MHz CB antenna output once and it would light up when the neighbor across the street transmitted, Or something like this: http://panteltje.nl/pub/testing_the_20_meter_inductive_loop_antenna_IMG_4536.JPG
