On Mon, 08 Jan 2024 11:14:08 -0500, legg <legg@nospam.magma.ca> wrote:

>On Sat, 06 Jan 2024 14:31:49 +0100, albert@cherry.(none) (albert)
>wrote:
>
>>I'm sitting on a heap of germanium transistors. From the time that
>>computers made of discrete germanium transistors were decommissioned.
>>Also 10 mm and 6 mm ferrite core.
>>Can I make on oscillator, that runs on 1V , preferably using
>>coils ? (Also trying to use LTSpice for the first time.)
>>I can measure inductance of coils thanks to the miracle component
>>testers from China.
>>
>>Groetjes Albert
>
>Oscillators operating at 1V and lower are basic elements of energy
>scavenging circuitry.
>
>A new design might use 0Vgs threshold mosfets.
>https://www.aldinc.com/ald_zerothresholdmosfet.php
>
>Below 700mV, a hobby circuit might benefit from a manual press-
>switch to get things started - a manual charge pump. Limited
>applications there.
>
>Once an oscillation is developed, higher voltages can be generated for
>conventional cctry to take over, if the source can supply the energy.
>
>Check out ADP5090-91, MAX20361, LTC3107 and LTC3119 to 'start'.
>
>RL

Enhancment-mode phemts, like SAV541, are cool. Turn-on threshold is
0.26v typ, and it goes to about 3 ohms rds-on with 0.5 on the gate.

On a sunny day (Mon, 08 Jan 2024 16:45:36 -0800) it happened John Larkin
<jl@997PotHill.com> wrote in <595ppihhdig9v84fu489dt1ghlh33b5co5@4ax.com>:

>On Mon, 08 Jan 2024 11:14:08 -0500, legg <legg@nospam.magma.ca> wrote:
>
>>On Sat, 06 Jan 2024 14:31:49 +0100, albert@cherry.(none) (albert)
>>wrote:
>>
>>>I'm sitting on a heap of germanium transistors. From the time that
>>>computers made of discrete germanium transistors were decommissioned.
>>>Also 10 mm and 6 mm ferrite core.
>>>Can I make on oscillator, that runs on 1V , preferably using
>>>coils ? (Also trying to use LTSpice for the first time.)
>>>I can measure inductance of coils thanks to the miracle component
>>>testers from China.
>>>
>>>Groetjes Albert
>>
>>Oscillators operating at 1V and lower are basic elements of energy
>>scavenging circuitry.
>>
>>A new design might use 0Vgs threshold mosfets.
>>https://www.aldinc.com/ald_zerothresholdmosfet.php
>>
>>Below 700mV, a hobby circuit might benefit from a manual press-
>>switch to get things started - a manual charge pump. Limited
>>applications there.
>>
>>Once an oscillation is developed, higher voltages can be generated for
>>conventional cctry to take over, if the source can supply the energy.
>>
>>Check out ADP5090-91, MAX20361, LTC3107 and LTC3119 to 'start'.
>>
>>RL
>
>Enhancment-mode phemts, like SAV541, are cool. Turn-on threshold is
>0.26v typ, and it goes to about 3 ohms rds-on with 0.5 on the gate.

From a few hundred mV to ?
https://panteltje.nl/pub/lighting_a_LED_with_a_candle_IMG_3604.GIF
https://panteltje.online/pub/lighting_a_LED_with_a_candle_hardware_IMG_3605.GIF
https://panteltje.online/pub/lighting_a_LED_with_a_candle_circuit_diagram_with_added_power_MOSFET.gif
https://panteltje.nl/pub/lighting_a_LED_with_a_candle_setup_IMG_3607.GIF

In article <94uipi5b8l1spe7ig4f0gvicts8pbvntt2@4ax.com>,
John Larkin <xx@yy.com> wrote:
>On Sat, 06 Jan 2024 14:31:49 +0100, albert@cherry.(none) (albert)
>wrote:
>
>>I'm sitting on a heap of germanium transistors. From the time that
>>computers made of discrete germanium transistors were decommissioned.
>>Also 10 mm and 6 mm ferrite core.
>>Can I make on oscillator, that runs on 1V , preferably using
>>coils ? (Also trying to use LTSpice for the first time.)
>>I can measure inductance of coils thanks to the miracle component
>>testers from China.
>>
>>Groetjes Albert
>
>
>1v should be easy with a ge transistor.
>
>People make oscillators that run off 10s of mV, but they usually use
>jfets. A depletion phemt would be interesting.
>
>Play with some ciruits in LTspice and post them here if you'd like us
>to discuss them.
>
>Is there an LT model of a germanium transistor?
>
>Do you have an oscilloscope?

I do. Contrary to comments I've seen, this is relevant.
I promise to showing the difference between
the LTspice model and experiment.

>
Groetjes Albert
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat purring. - the Wise from Antrim -

In article <414470b6-3a02-4ccc-8854-dc96927fc311n@googlegroups.com>,
Anthony William Sloman <bill.sloman@ieee.org> wrote:
>On Monday, January 8, 2024 at 8:05:12 AM UTC+11, Joe Gwinn wrote:
>> On Sun, 7 Jan 2024 09:42:23 +0000, l...@poppyrecords.invalid.invalid
>> (Liz Tuddenham) wrote:
>>
>> >Joe Gwinn <joeg...@comcast.net> wrote:
>> >
>> >
>> >> I don't know the origin. Not German. Nor Icelandic (which is
>> >> basically Old Norse). But it is true in Norwegian, and Danish.
>> >
>> >I had a feeling the O/P was Dutch.
>> Turns out to be true.
>>
>> I checked Dutch, which it turns out also spins its cats, and oil is
>> olie. So it almost parallels Swedish, Norwegian, and Danish. Maybe
>> the connecting theme is who conquered who over the centuries.
>
>Not in this case. The Dutch republic in its glory days had a large printed industry , which exported to most of northern Europe, in Dutch.

The Dutch language is old. We had to read an 8th century poem
about Charlemagn.(Karel ende Elegast).
It was kind of hard to understand but definitely the same language.
Nobody imposed a language upon the inhabitants of now The Netherlands.
And to lift all doubt, I'm Dutch.
>
>The Germans - mostly Frederick the Great - invented high German to minimise their cultural influence, and boost their own printing industry, Noah Webster
>style. Military conquest didn't really come into it - at least not directly.
>
>--
>Bill Sloman, Sydney
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat purring. - the Wise from Antrim -

In article <1qmyorb.1du7clv1xyko8wN%liz@poppyrecords.invalid.invalid>,
Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
>albert <albert@cherry.(none)> wrote:
>
>> In article <1qmx7n9.x80ybk1jx7h1cN%liz@poppyrecords.invalid.invalid>,
>> Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
>> >albert <albert@cherry.(none)> wrote:
>> >
>> >[...]
>> >
>> >I realise this is completely off-topic but in your signature I see:
>> >"First gain is a cat spinning. ". This is an expression I have never
>> >heard before, could you tell me what it means?
>>
>> That is a translation error. Meant is a "cat purring".
>> Thanks for pointing this out.
>> [The "Wijze van Antrim" actually exists, in Dutch literature.]
>
>Thanks, does it mean something like: "You know you are winning when the
>cat begins to purr"?

No. All these expressions means approximately the same thing.
If make profit early, that means nothing. It is a promise and it
is nice, like a cat purring, it buys you nothing.

>
> It is always interesting to see wise sayings from other languages.
>Dutch seems to be particularly rich in these - the Dutch sense of humour
>is very similar to a certain type of English humour that appeals to me.

Thanks. Daniel van der Vat was a writer. He also published
several children books under the pseudo Daan Zonderland.
Like Alice in Wonderland they are worth reading as an adult.
There are little jokes, for those who are acquainted with Christian mythology.
The man Pieter commands the heavenly ships that sails the skies
where little angles drop rain or snow on our heads.
He gets furious if one of the visitors is a rooster...
>
>-
>~iz Tuddenham ~

Groetjes Albert
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat purring. - the Wise from Antrim -

In article <ngempi1nktan8bvp4f77j06qu7nudg72v3@4ax.com>,
John Larkin <xx@yy.com> wrote:
>
>Some WWII-vintage infrared sniperscopes used a watch escapement to
>briefly close a contact at about 1 Hz, with a D-cell driving a step-up
>transformer and a cold-cathode or selenium retifier.

Infrared WWII. I do not rememver hearing any thing about that.

I heard the stories of 14 year old girl snipers who saw
better in the dark than the 18 year old or older Germans.

Groetjes Albert
>
--
Don't praise the day before the evening. One swallow doesn't make spring.
You must not say "hey" before you have crossed the bridge. Don't sell the
hide of the bear until you shot it. Better one bird in the hand than ten in
the air. First gain is a cat purring. - the Wise from Antrim -

albert <albert@cherry.(none)> wrote:

> In article <1qmyorb.1du7clv1xyko8wN%liz@poppyrecords.invalid.invalid>,
> Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
[...]
> >Thanks, does it mean something like: "You know you are winning when the
> >cat begins to purr"?
>
> No. All these expressions means approximately the same thing.
> If make profit early, that means nothing. It is a promise and it
> is nice, like a cat purring, it buys you nothing.

Thank you, it is an interesting way of expressing the idea.

--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

On 8/01/2024 2:07 am, Liz Tuddenham wrote:
> Bill Sloman <bill.sloman@ieee.org> wrote:
>
> [...]
>> Any ferromagnetic core material will saturate at a high enough flux -
>> there's nothing special about a ring core except that you get less
>> cross-section to saturate for every gram of relatively expensive ferrite
>> that you buy.
>
> ...and no air gap.

Commercial ferrites are mostly sold as mating pairs, with optically flat
mating faces.

Gapped cores have the inner face ground back to give a stable and
precise gap, and a stable and tolerably precise inductance

https://www.tdk-electronics.tdk.com/inf/80/db/fer/rm_8.pdf

The smallest gap listed is 40 micron.

A ring core isn't significantly different from an ungapped core pair.

For the RM8 core the magnetic path length is about 38mm. Even for
highest permeability core material - N30 - ue-5700 +/-30% - that equates
to 7 micron air gap, and the mating faces come a lot closer than that.

--
Bill Sloman, Sydney

On 09/01/2024 13:53, Bill Sloman wrote:
> On 8/01/2024 2:07 am, Liz Tuddenham wrote:
>> Bill Sloman <bill.sloman@ieee.org> wrote:
>>
>> [...]
>>> Any ferromagnetic core material will saturate at a high enough flux -
>>> there's nothing special about a ring core except that you get less
>>> cross-section to saturate for every gram of relatively expensive ferrite
>>> that you buy.
>>
>> ...and no air gap.
>
> Commercial ferrites are mostly sold as mating pairs, with optically flat
> mating faces.
>
> Gapped cores have the inner face ground back to give a stable and
> precise gap, and a stable and tolerably precise inductance
>
> https://www.tdk-electronics.tdk.com/inf/80/db/fer/rm_8.pdf
>
> The smallest gap listed is 40 micron.
>
> A ring core isn't significantly different from an ungapped core pair.

You can get gapped toroids...

https://megatron.ch/infocenter/gaptoroids.pdf

....and toroids with 'distributed gaps', ie insulated powder...

https://www.mag-inc.com/Products/Selecting-a-Distributed-Air-Gap-Powder-Core-for-Fl

<snipped>

--
Cheers
Clive

On Tue, 09 Jan 2024 12:17:36 +0100, albert@cherry.(none) (albert)
wrote:

>In article <ngempi1nktan8bvp4f77j06qu7nudg72v3@4ax.com>,
>John Larkin <xx@yy.com> wrote:
>>
>>Some WWII-vintage infrared sniperscopes used a watch escapement to
>>briefly close a contact at about 1 Hz, with a D-cell driving a step-up
>>transformer and a cold-cathode or selenium retifier.
>
>Infrared WWII. I do not rememver hearing any thing about that.
>
>I heard the stories of 14 year old girl snipers who saw
>better in the dark than the 18 year old or older Germans.
>
>Groetjes Albert
>>

Google ww2 infrared scope

When I was a kid, I used to get books from the US Government Printing
Office; I think they were free. One was all about infrared
sniperscopes.

They had low optical gain so used basically a filtered auto headlight
to illuminate the target. The first-gen tubes were hockey-puck
proximity focussed, not very good. 2nd gen tubes were long and skinny,
ran at higher voltage, had some optical gain, and electronically
inverted the image, which helped the optics.

On 1/6/24 5:31 AM, albert wrote:
> I'm sitting on a heap of germanium transistors. From the time that
> computers made of discrete germanium transistors were decommissioned.
> Also 10 mm and 6 mm ferrite core.
> Can I make on oscillator, that runs on 1V , preferably using
> coils ? (Also trying to use LTSpice for the first time.)
> I can measure inductance of coils thanks to the miracle component
> testers from China.
>

Yes, but these transistors will be very old. Ge transistors can
deteriorate over time, increasing leakage for example.

The easiest way to build an oscillator that runs at <1V is to use a
small JFET. Of course, then it won't have a genuine 60's feel to it :-)

--
Regards, Joerg

http://www.analogconsultants.com/

On Tue, 09 Jan 2024 11:53:23 +0100, albert@cherry.(none) (albert)
wrote:

>In article <414470b6-3a02-4ccc-8854-dc96927fc311n@googlegroups.com>,
>Anthony William Sloman <bill.sloman@ieee.org> wrote:
>>On Monday, January 8, 2024 at 8:05:12 AM UTC+11, Joe Gwinn wrote:
>>> On Sun, 7 Jan 2024 09:42:23 +0000, l...@poppyrecords.invalid.invalid
>>> (Liz Tuddenham) wrote:
>>>
>>> >Joe Gwinn <joeg...@comcast.net> wrote:
>>> >
>>> >
>>> >> I don't know the origin. Not German. Nor Icelandic (which is
>>> >> basically Old Norse). But it is true in Norwegian, and Danish.
>>> >
>>> >I had a feeling the O/P was Dutch.
>>> Turns out to be true.
>>>
>>> I checked Dutch, which it turns out also spins its cats, and oil is
>>> olie. So it almost parallels Swedish, Norwegian, and Danish. Maybe
>>> the connecting theme is who conquered who over the centuries.
>>
>>Not in this case. The Dutch republic in its glory days had a large printed industry , which exported to most of northern Europe, in Dutch.
>
>The Dutch language is old. We had to read an 8th century poem
>about Charlemagn.(Karel ende Elegast).

Sir Walter Scott, ca 1800, is easy to read. Chaucer, around 1400, is
not.

On Sunday 7 January 2024 at 11:20:39 UTC, none albert wrote:
> In article <1qmx7n9.x80ybk1jx7h1cN%l...@poppyrecords.invalid.invalid>,
> Liz Tuddenham <l...@poppyrecords.invalid.invalid> wrote:
> >albert <albert@cherry.(none)> wrote:
> >
> >[...]
> >
> >I realise this is completely off-topic but in your signature I see:
> >"First gain is a cat spinning. ". This is an expression I have never
> >heard before, could you tell me what it means?
> That is a translation error. Meant is a "cat purring".

sometimes when they purr they do spin. 0 point something rpm.

On a sunny day (Sat, 06 Jan 2024 08:13:45 -0800) it happened John Larkin
<jl@997PotHill.com> wrote in <kfuipih5uvehko3ebb35s4n4r8qcai1vpj@4ax.com>:

>On Sat, 06 Jan 2024 14:50:17 GMT, Jan Panteltje <alien@comet.invalid>
>wrote:
>
>>On a sunny day (Sat, 06 Jan 2024 14:31:49 +0100) it happened
>>albert@cherry.(none) (albert) wrote in
>><nnd$30302dcf$1e37b7a5@bbcc4a9e0386ea66>:
>>
>>>I'm sitting on a heap of germanium transistors. From the time that
>>>computers made of discrete germanium transistors were decommissioned.
>>>Also 10 mm and 6 mm ferrite core.
>>>Can I make on oscillator, that runs on 1V , preferably using
>>>coils ?
>>
>>Yes, Ge transistors start conducting from 150 mV Vbe to maybe 300 mV, so much less than Si .7 V,
>>Any LC oscillator will work.
>>Tuned circuit LC in the collector, feedback 1 turn (correct phase) to the base?
>>
>
>Or something like this
>
>https://ecstudiosystems.com/discover/textbooks/basic-electronics/oscillators/images/colpitts-oscillator.jpg
>
>except it needs a power supply.
>
>We were just discussing source-follower Colpitts oscillators yesterday
>and concluded that we don't understand them.
>
>