Reply by legg January 11, 20162016-01-11
On Sun, 10 Jan 2016 08:08:36 -0500, DecadentLinuxUserNumeroUno
<DLU1@DecadentLinuxUser.org> wrote:

>On Sun, 10 Jan 2016 04:53:23 -0600, John S <Sophi.2@invalid.org> Gave >us: > >>On 1/7/2016 9:03 AM, DecadentLinuxUserNumeroUno wrote: >>> On Thu, 07 Jan 2016 09:58:04 -0500, legg <legg@nospam.magma.ca> Gave us: >>> >>>> On Mon, 4 Jan 2016 20:36:18 -0800 (PST), dakupoto@gmail.com wrote: >>>> >>>> >>>>> I replaced the transformer with an air core >>>>> transformer, obtained by carefully removing >>>>> the iron core of the transformer used above, >>>>> The winding is completely intact, tested by >>>>> measuring the winding resistance of both >>>>> the primary and secondary, with the transformer >>>>> not connected. I am fully aware of the reluctance >>>>> issues but this time the transformer output >>>>> is just about 0.5 Volts - 1.0 Volts AC. So >>>>> what is going wrong ? All hints/suggestions >>>>> are welcome. Thanks in advance for your help. >>>> >>>> For your own benefit, instead of removing the core, >>>> you might instead reconfigure it so that an adjustible gap is >>>> possible. >>>> >>>> EI stampings can be grouped with 'all E' and 'all I' groupings. >>>> >>>> Gradually increasing the gap in paper-width-thick increments will show >>>> you what's happening as you change the effective permeability of the >>>> magnetic core from the initially high value of silicon steel, to that >>>> of free space. ( uo = 4 x pi x E-7 ) >>>> >>>> RL >>> >>> Can we really ever put a price on space? >>> >> >>Of course. Just ask NASA. > > I DLd a pic of part of the hifi IPAC probe the other day. I used to >make some pretty elaborate and refined SMA runs in some of my rack gear, >but these guys are deep into it! > >http://www.mpifr-bonn.mpg.de/776874/zoom.jpg
Now there's some pricey real estate. RL
Reply by DecadentLinuxUserNumeroUno January 10, 20162016-01-10
On Sun, 10 Jan 2016 09:37:03 -0500, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> Gave us:

>On 01/10/2016 08:44 AM, DecadentLinuxUserNumeroUno wrote: >> On Sun, 10 Jan 2016 05:11:40 -0800 (PST), Phil Hobbs >> <pcdhobbs@gmail.com> Gave us: >> >>>>> Can we really ever put a price on space? >>>> >>> >>>> Of course. Just ask NASA. >>> >>> I'm running a promotion this week--prime unoccupied volume a stone's throw from sunny Pluto. Only $1 per thousand cubic feet. >>> >>> Serious enquiries only. >>> >>> Cheers >>> >>> Phil Hobbs >> >> >> Only interested if you can offer one day transit times.. >> > >With a 1 cubic mile purchase, I'll Fedex you the deed (quitclaim of >course). A super deal at only $147,197,952. > >Cheers > >Phil Hobbs
I'll come close the deal right after I claim my power ball jackpot of 1.6 Billion dollars (which is what it will be by the next drawing date).
Reply by January 10, 20162016-01-10
On Tuesday, January 5, 2016 at 5:36:22 PM UTC+13, daku...@gmail.com wrote:
> Could some electronics guru please provide > some hints/suggestions to the following ? > First, I built a simple DC->AC push-pull > inverter with a 12 Volt 7AH sealed lead > acid cell battery. The output transformer > is a 120 Volt(primary) and 6-0-6 1.5 Amp > (max) secondary. This configuration worked > fine, and a 60 Watt incandescent lamp > connected to the transformer output terminals > provided steady light. > > I replaced the transformer with an air core > transformer, obtained by carefully removing > the iron core of the transformer used above, > The winding is completely intact, tested by > measuring the winding resistance of both > the primary and secondary, with the transformer > not connected. I am fully aware of the reluctance > issues but this time the transformer output > is just about 0.5 Volts - 1.0 Volts AC. So > what is going wrong ? All hints/suggestions > are welcome. Thanks in advance for your help.
Faradays law - Voltage induced = N X rate of change of flux. No flux is reaching the secondary!
Reply by krw January 10, 20162016-01-10
On Sun, 10 Jan 2016 04:53:23 -0600, John S <Sophi.2@invalid.org>
wrote:

>On 1/7/2016 9:03 AM, DecadentLinuxUserNumeroUno wrote: >> On Thu, 07 Jan 2016 09:58:04 -0500, legg <legg@nospam.magma.ca> Gave us: >> >>> On Mon, 4 Jan 2016 20:36:18 -0800 (PST), dakupoto@gmail.com wrote: >>> >>> >>>> I replaced the transformer with an air core >>>> transformer, obtained by carefully removing >>>> the iron core of the transformer used above, >>>> The winding is completely intact, tested by >>>> measuring the winding resistance of both >>>> the primary and secondary, with the transformer >>>> not connected. I am fully aware of the reluctance >>>> issues but this time the transformer output >>>> is just about 0.5 Volts - 1.0 Volts AC. So >>>> what is going wrong ? All hints/suggestions >>>> are welcome. Thanks in advance for your help. >>> >>> For your own benefit, instead of removing the core, >>> you might instead reconfigure it so that an adjustible gap is >>> possible. >>> >>> EI stampings can be grouped with 'all E' and 'all I' groupings. >>> >>> Gradually increasing the gap in paper-width-thick increments will show >>> you what's happening as you change the effective permeability of the >>> magnetic core from the initially high value of silicon steel, to that >>> of free space. ( uo = 4 x pi x E-7 ) >>> >>> RL >> >> Can we really ever put a price on space? >> > >Of course. Just ask NASA.
Nah, they're an infinite money sink.
Reply by Phil Hobbs January 10, 20162016-01-10
On 01/10/2016 08:44 AM, DecadentLinuxUserNumeroUno wrote:
> On Sun, 10 Jan 2016 05:11:40 -0800 (PST), Phil Hobbs > <pcdhobbs@gmail.com> Gave us: > >>>> Can we really ever put a price on space? >>> >> >>> Of course. Just ask NASA. >> >> I'm running a promotion this week--prime unoccupied volume a stone's throw from sunny Pluto. Only $1 per thousand cubic feet. >> >> Serious enquiries only. >> >> Cheers >> >> Phil Hobbs > > > Only interested if you can offer one day transit times.. >
With a 1 cubic mile purchase, I'll Fedex you the deed (quitclaim of course). A super deal at only $147,197,952. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Reply by DecadentLinuxUserNumeroUno January 10, 20162016-01-10
On Sun, 10 Jan 2016 05:11:40 -0800 (PST), Phil Hobbs
<pcdhobbs@gmail.com> Gave us:

>>> &#2013266080; &#2013266080;Can we really ever put a price on space? >> > >>Of course. Just ask NASA. > >I'm running a promotion this week--prime unoccupied volume a stone's throw from sunny Pluto. Only $1 per thousand cubic feet. > >Serious enquiries only. > >Cheers > >Phil Hobbs
Only interested if you can offer one day transit times..
Reply by Phil Hobbs January 10, 20162016-01-10
>> &#2013266080; &#2013266080;Can we really ever put a price on space? >
>Of course. Just ask NASA.
I'm running a promotion this week--prime unoccupied volume a stone's throw from sunny Pluto. Only $1 per thousand cubic feet. Serious enquiries only. Cheers Phil Hobbs
Reply by DecadentLinuxUserNumeroUno January 10, 20162016-01-10
On Sun, 10 Jan 2016 04:53:23 -0600, John S <Sophi.2@invalid.org> Gave
us:

>On 1/7/2016 9:03 AM, DecadentLinuxUserNumeroUno wrote: >> On Thu, 07 Jan 2016 09:58:04 -0500, legg <legg@nospam.magma.ca> Gave us: >> >>> On Mon, 4 Jan 2016 20:36:18 -0800 (PST), dakupoto@gmail.com wrote: >>> >>> >>>> I replaced the transformer with an air core >>>> transformer, obtained by carefully removing >>>> the iron core of the transformer used above, >>>> The winding is completely intact, tested by >>>> measuring the winding resistance of both >>>> the primary and secondary, with the transformer >>>> not connected. I am fully aware of the reluctance >>>> issues but this time the transformer output >>>> is just about 0.5 Volts - 1.0 Volts AC. So >>>> what is going wrong ? All hints/suggestions >>>> are welcome. Thanks in advance for your help. >>> >>> For your own benefit, instead of removing the core, >>> you might instead reconfigure it so that an adjustible gap is >>> possible. >>> >>> EI stampings can be grouped with 'all E' and 'all I' groupings. >>> >>> Gradually increasing the gap in paper-width-thick increments will show >>> you what's happening as you change the effective permeability of the >>> magnetic core from the initially high value of silicon steel, to that >>> of free space. ( uo = 4 x pi x E-7 ) >>> >>> RL >> >> Can we really ever put a price on space? >> > >Of course. Just ask NASA.
I DLd a pic of part of the hifi IPAC probe the other day. I used to make some pretty elaborate and refined SMA runs in some of my rack gear, but these guys are deep into it! http://www.mpifr-bonn.mpg.de/776874/zoom.jpg
Reply by John S January 10, 20162016-01-10
On 1/7/2016 9:03 AM, DecadentLinuxUserNumeroUno wrote:
> On Thu, 07 Jan 2016 09:58:04 -0500, legg <legg@nospam.magma.ca> Gave us: > >> On Mon, 4 Jan 2016 20:36:18 -0800 (PST), dakupoto@gmail.com wrote: >> >> >>> I replaced the transformer with an air core >>> transformer, obtained by carefully removing >>> the iron core of the transformer used above, >>> The winding is completely intact, tested by >>> measuring the winding resistance of both >>> the primary and secondary, with the transformer >>> not connected. I am fully aware of the reluctance >>> issues but this time the transformer output >>> is just about 0.5 Volts - 1.0 Volts AC. So >>> what is going wrong ? All hints/suggestions >>> are welcome. Thanks in advance for your help. >> >> For your own benefit, instead of removing the core, >> you might instead reconfigure it so that an adjustible gap is >> possible. >> >> EI stampings can be grouped with 'all E' and 'all I' groupings. >> >> Gradually increasing the gap in paper-width-thick increments will show >> you what's happening as you change the effective permeability of the >> magnetic core from the initially high value of silicon steel, to that >> of free space. ( uo = 4 x pi x E-7 ) >> >> RL > > Can we really ever put a price on space? >
Of course. Just ask NASA.
Reply by George Herold January 8, 20162016-01-08
On Friday, January 8, 2016 at 12:22:43 AM UTC-5, daku...@gmail.com wrote:
> On Thursday, January 7, 2016 at 10:00:07 AM UTC-5, legg wrote: > > On Mon, 4 Jan 2016 20:36:18 -0800 (PST), dakupoto@gmail.com wrote: > > > > > > >I replaced the transformer with an air core > > >transformer, obtained by carefully removing > > >the iron core of the transformer used above, > > >The winding is completely intact, tested by > > >measuring the winding resistance of both > > >the primary and secondary, with the transformer > > >not connected. I am fully aware of the reluctance > > >issues but this time the transformer output > > >is just about 0.5 Volts - 1.0 Volts AC. So > > >what is going wrong ? All hints/suggestions > > >are welcome. Thanks in advance for your help. > > > > For your own benefit, instead of removing the core, > > you might instead reconfigure it so that an adjustible gap is > > possible. > > > > EI stampings can be grouped with 'all E' and 'all I' groupings. > > > > Gradually increasing the gap in paper-width-thick increments will show > > you what's happening as you change the effective permeability of the > > magnetic core from the initially high value of silicon steel, to that > > of free space. ( uo = 4 x pi x E-7 ) > > > > RL > > Thanks to each of for your helpful comments. Initially, the astable multivibrator that I > am using to excite the bifilar winding had > an oscillation frequency of approx. 5.5 KHz > (as estimated from o'scope traces), but now, after some modifications, the oscillation frequency has been boosted to 100 KHz. Now > the output is 8 Volts AC, across the primary > of the air core transformer, and that is > sufficient for my initial proof of concept design.
If you want a higher frequency transformer there are all sorts of ferrite cores that you could maybe use. Is there a lot of power involved? George H.