On Tuesday, 4 September 2018 17:35:41 UTC+1, John Larkin wrote:> On Mon, 3 Sep 2018 21:51:17 -0700 (PDT), whit3rd <whit3rd@gmail.com> > wrote: > > >On Monday, September 3, 2018 at 1:07:08 AM UTC-7, 69883925...@nospam.org wrote: > > > >> And do not forget the 12V DC motor driving a 350V DC generator solution :-) > > > >Yes, an electric motor and a rubber band is the basis of many a > >van de Graaff generator, but it's easier to get 350 kV than it > >is to get 350W that way. That's REAL high voltage gain. > > What's the wall-plug efficiency of a Van de Graaff?I'm sure it's zero, +/- not very much. NT
Very high gain transformerless boost converter - is it possible
Started by ●September 2, 2018
Reply by ●September 4, 20182018-09-04
Reply by ●September 4, 20182018-09-04
On Tuesday, 4 September 2018 18:51:31 UTC+1, John Larkin wrote:> On Tue, 4 Sep 2018 09:40:37 -0700, John Robertson <spam@flippers.com> > wrote: > > >On 2018/09/04 9:34 AM, John Larkin wrote: > >> On Tue, 4 Sep 2018 09:30:04 -0700, John Robertson <spam@flippers.com> > >> wrote: > >> > >>> On 2018/09/03 7:55 AM, John Larkin wrote: > >>>> On 3 Sep 2018 05:15:10 -0700, Winfield Hill <hill@rowland.harvard.edu> > >>>> wrote: > >>>> > >>>>> <698839253X6D445TD@nospam.org> wrote... > >>>>>> > >>>>>> And do not forget the 12V DC motor driving a 350V DC generator solution :-) > >>>> > >>>> Dynamotor. For regulation, control the field of the generator. I think > >>>> that's an amplidyne or something. They used them for things like > >>>> aiming the guns on battleships. > >>>> > >>>>> > >>>>> 100 relays switching 100 Li-ion cells from parallel to series. > >>>> > >>>> Overkill. Two banks of 30 relays each should do it. > >>>> > >>>> > >>> > >>> Overkill. Use 4PDT 12VDC relays and I think you are down to around 50 > >>> relays...(2 batteries/relay). > >>> > >>> John > >> > >> There is my relay version of the Cockcroft妨alton multiplier that Phil > >> calls the Groucho Marx Generator. > >> > >> > > > >I'd like to see that schematic! I work on both EM and SS equipment and > >so enjoy all forms of electrical abuse... > > > >John :-#)# > > My mistake. It was Harpo. > > https://www.dropbox.com/s/qycxyrty0hkkzo1/Harpo_Marx.JPG?raw=1 > > I wonder if there is a variant that doesn't apply so much voltage to > the relay contacts. > > How about a rotating cam that drives a lot of switch contacts? Or a > rotating insulated shaft that drives a lot of generators (stepper > motors would work) wired in series. > > I'd like to get a bunch of doorknob capacitors, charge them each to > 30KV, and then stack or drop them inside a plexiglass tube.I've got it. Charge each doorknob to 30kV then fire it into the top of the plastic tube with a toy cannon. Rotating contacts top & bottom extract the output from the pile of Cs, while they're let out at the bottom at the same rate as they're fired into the top. NT
Reply by ●September 4, 20182018-09-04
On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote:> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > > >>"I think the record player speed regulator was frictional hence lossy. " > > > >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > > I could imagine a nearly lossless regulator for a wind-up Victrola, > but not with 1930's technology.Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. NT
Reply by ●September 4, 20182018-09-04
On Tuesday, September 4, 2018 at 6:19:29 PM UTC-4, tabb...@gmail.com wrote:> On Tuesday, 4 September 2018 17:35:41 UTC+1, John Larkin wrote: > > On Mon, 3 Sep 2018 21:51:17 -0700 (PDT), whit3rd <whit3rd@gmail.com> > > wrote: > > > > >On Monday, September 3, 2018 at 1:07:08 AM UTC-7, 69883925...@nospam.org wrote: > > > > > >> And do not forget the 12V DC motor driving a 350V DC generator solution :-) > > > > > >Yes, an electric motor and a rubber band is the basis of many a > > >van de Graaff generator, but it's easier to get 350 kV than it > > >is to get 350W that way. That's REAL high voltage gain. > > > > What's the wall-plug efficiency of a Van de Graaff? > > I'm sure it's zero, +/- not very much. > > > NTHuh, I have no idea, but I'd bet (a beverage) it's better than 1%. George H. I took data at an FEL that used a big ass Van de Graff to accelerate the electrons.
Reply by ●September 4, 20182018-09-04
On 09/04/2018 06:21 PM, tabbypurr@gmail.com wrote:> On Tuesday, 4 September 2018 18:51:31 UTC+1, John Larkin wrote: >> On Tue, 4 Sep 2018 09:40:37 -0700, John Robertson <spam@flippers.com> >> wrote: >> >>> On 2018/09/04 9:34 AM, John Larkin wrote: >>>> On Tue, 4 Sep 2018 09:30:04 -0700, John Robertson <spam@flippers.com> >>>> wrote: >>>> >>>>> On 2018/09/03 7:55 AM, John Larkin wrote: >>>>>> On 3 Sep 2018 05:15:10 -0700, Winfield Hill <hill@rowland.harvard.edu> >>>>>> wrote: >>>>>> >>>>>>> <698839253X6D445TD@nospam.org> wrote... >>>>>>>> >>>>>>>> And do not forget the 12V DC motor driving a 350V DC generator solution :-) >>>>>> >>>>>> Dynamotor. For regulation, control the field of the generator. I think >>>>>> that's an amplidyne or something. They used them for things like >>>>>> aiming the guns on battleships. >>>>>> >>>>>>> >>>>>>> 100 relays switching 100 Li-ion cells from parallel to series. >>>>>> >>>>>> Overkill. Two banks of 30 relays each should do it. >>>>>> >>>>>> >>>>> >>>>> Overkill. Use 4PDT 12VDC relays and I think you are down to around 50 >>>>> relays...(2 batteries/relay). >>>>> >>>>> John >>>> >>>> There is my relay version of the Cockcroft妨alton multiplier that Phil >>>> calls the Groucho Marx Generator. >>>> >>>> >>> >>> I'd like to see that schematic! I work on both EM and SS equipment and >>> so enjoy all forms of electrical abuse... >>> >>> John :-#)# >> >> My mistake. It was Harpo. >> >> https://www.dropbox.com/s/qycxyrty0hkkzo1/Harpo_Marx.JPG?raw=1 >> >> I wonder if there is a variant that doesn't apply so much voltage to >> the relay contacts. >> >> How about a rotating cam that drives a lot of switch contacts? Or a >> rotating insulated shaft that drives a lot of generators (stepper >> motors would work) wired in series. >> >> I'd like to get a bunch of doorknob capacitors, charge them each to >> 30KV, and then stack or drop them inside a plexiglass tube. > > I've got it. Charge each doorknob to 30kV then fire it into the top of the plastic tube with a toy cannon. Rotating contacts top & bottom extract the output from the pile of Cs, while they're let out at the bottom at the same rate as they're fired into the top. > > > NT >There are mechanical generators that do that by putting HV axial caps on what's basically a bandolier. Similar to a van de Graaf but with a lot more stooch. 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 ●September 4, 20182018-09-04
On Tue, 4 Sep 2018 15:24:35 -0700 (PDT), tabbypurr@gmail.com wrote:>On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote: >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: >> >> >>"I think the record player speed regulator was frictional hence lossy. " >> > >> >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... >> >> I could imagine a nearly lossless regulator for a wind-up Victrola, >> but not with 1930's technology. > >Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. > > >NTI still feel sorry for mechanical engineers who have no decent equivalent to a switching regulator. -- John Larkin Highland Technology, Inc trk jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●September 4, 20182018-09-04
On Wednesday, September 5, 2018 at 11:29:48 AM UTC+10, John Larkin wrote:> On Tue, 4 Sep 2018 15:24:35 -0700 (PDT), tabbypurr@gmail.com wrote: > > >On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote: > >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > >> > >> >>"I think the record player speed regulator was frictional hence lossy. " > >> > > >> >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > >> > >> I could imagine a nearly lossless regulator for a wind-up Victrola, > >> but not with 1930's technology. > > > >Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. > > I still feel sorry for mechanical engineers who have no decent > equivalent to a switching regulator.It's called a gearbox. Not suitable for gramophone speed regulation, but belt drive turntables offer other approaches (not that any of them would be a sensible choice in real life). -- Bill Sloman, Sydney
Reply by ●September 4, 20182018-09-04
On Wednesday, 5 September 2018 02:26:51 UTC+1, Phil Hobbs wrote:> On 09/04/2018 06:21 PM, tabbypurr wrote: > > On Tuesday, 4 September 2018 18:51:31 UTC+1, John Larkin wrote:> >> I'd like to get a bunch of doorknob capacitors, charge them each to > >> 30KV, and then stack or drop them inside a plexiglass tube. > > > > I've got it. Charge each doorknob to 30kV then fire it into the top of the plastic tube with a toy cannon. Rotating contacts top & bottom extract the output from the pile of Cs, while they're let out at the bottom at the same rate as they're fired into the top. > > > > > > NT > > > > There are mechanical generators that do that by putting HV axial caps on > what's basically a bandolier. Similar to a van de Graaf but with a lot > more stooch. > > Cheers > > Phil HobbsOh, not seen those. NT
Reply by ●September 4, 20182018-09-04
On Wednesday, 5 September 2018 01:09:41 UTC+1, George Herold wrote:> On Tuesday, September 4, 2018 at 6:19:29 PM UTC-4, tabby wrote: > > On Tuesday, 4 September 2018 17:35:41 UTC+1, John Larkin wrote: > > > On Mon, 3 Sep 2018 21:51:17 -0700 (PDT), whit3rd <whit3rd@gmail.com> > > > wrote: > > > >On Monday, September 3, 2018 at 1:07:08 AM UTC-7, 69883925...@nospam.org wrote: > > > > > > > >> And do not forget the 12V DC motor driving a 350V DC generator solution :-) > > > > > > > >Yes, an electric motor and a rubber band is the basis of many a > > > >van de Graaff generator, but it's easier to get 350 kV than it > > > >is to get 350W that way. That's REAL high voltage gain. > > > > > > What's the wall-plug efficiency of a Van de Graaff? > > > > I'm sure it's zero, +/- not very much. > > > > > > NT > > Huh, I have no idea, but I'd bet (a beverage) it's better than 1%. > > George H. > I took data at an FEL that used a big ass Van de Graff to > accelerate the electrons.If I were really going to place a bet I'd take you on. I daresay there's a fair difference between the latest higher-tech van de graaf and something from their heyday. NT
Reply by ●September 4, 20182018-09-04
On Wednesday, 5 September 2018 02:29:48 UTC+1, John Larkin wrote:> On Tue, 4 Sep 2018 15:24:35 -0700 (PDT), tabbypurr wrote: > >On Tuesday, 4 September 2018 22:13:06 UTC+1, John Larkin wrote: > >> On Tue, 4 Sep 2018 13:56:38 -0700 (PDT), jurb6006@gmail.com wrote: > >> > >> >>"I think the record player speed regulator was frictional hence lossy. " > >> > > >> >Yes but against a spring that's wound up that is exactly what is needed. Electric motor not so much... > >> > >> I could imagine a nearly lossless regulator for a wind-up Victrola, > >> but not with 1930's technology. > > > >Were CVs (continuously variable ratio gears) not available then? I assume the reason to not use them was slow controller response loop. > > > > > >NT > > I still feel sorry for mechanical engineers who have no decent > equivalent to a switching regulator.There is the hit & miss engine. Not quite the same frequency response though. I guess it's more equivalent to the Philips G8 style triac & dropper PSU that either let a whole half-cycle through or didn't. NT
