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Oscillators without transistors

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mrda...@gmail.com

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Oct 17, 2018, 3:33:22 PM10/17/18
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Hello,

What are some examples of oscillators which don't require transistors or vacuum tubes?

So far I found relay oscillators and the Pearson-Anson oscillator.

Does the Pearson-Anson oscillator require a high-voltage neon lamp, or would it work on LEDs as well?
https://en.wikipedia.org/wiki/Pearson%E2%80%93Anson_effect

Relay oscillators look neat too but I don't imagine they would last very long at high frequencies.
https://www.youtube.com/watch?v=WuG4nOyF99s

Thanks,

Michael

Phil Hobbs

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Oct 17, 2018, 3:47:33 PM10/17/18
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The neon bulb thing only works because the bulb turns itself off
abruptly at low voltage, then doesn't turn on again immediately as the
voltage recovers. This hysteresis is why it works.

Other non-transistor, non-tube oscillators:

Electromechanical buzzers
Mechanical clock balance wheels
Coffee percolators
Baseball cards in bike spokes
Thermoacoustic refrigerators
Dog whistles
Ocarinas
Blowing over a beer bottle
Slinky going downstairs
Bay of Fundy
Internal combustion engine piston

Tunnel diode oscillator
SCR relaxation oscillator

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

David Snowdon

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Oct 17, 2018, 3:51:53 PM10/17/18
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Negative resistance spark gap ?

High frequency alternator ?
As I recall, Fessenden used a 100 KHz generator to transmit music and
voice in 1906.

David
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Tom Gardner

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Oct 17, 2018, 8:05:27 PM10/17/18
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Tunnel diodes
Gunn diodes

jf...@my-deja.com

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Oct 17, 2018, 8:21:43 PM10/17/18
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masers
lasers
spin-torque oscillators

default

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Oct 17, 2018, 8:46:42 PM10/17/18
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When I was in high school I built this rather elaborate relay
oscillator to dial a pulse type telephone. One relay developed
pulses, another was rigged as a monostable to time the pulse train to
dial a particular number. A rotary stepper relay could read the holes
in cards and cycle through some crude punch cards to dial (worked but
not well)

Scr's can be made to oscillate, of course unijunctions, some negative
resistance diodes like tunnel/gunn, electro-mechanical toys using
magnets and leaf/reed switches or transistors to energize coils,
old-time magnetic earphones and carbon mikes to develop feedback,
tuning forks with feedback drivers, propagation delay devices, arc
lights, early radio transmitters that used motors driving many-pole
alternators, spark-excited Tesla coils...


mrda...@gmail.com

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Oct 17, 2018, 10:32:04 PM10/17/18
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Ah ok, thanks. While I was at the university I was under the impression that one could create an oscillator with a combination of resistor, inductor and capacitor, but now I see most electronic oscillators require a transistor of some sort.

Michael

Jasen Betts

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Oct 18, 2018, 1:31:08 AM10/18/18
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On 2018-10-17, mrda...@gmail.com <mrda...@gmail.com> wrote:
> Hello,
>
> What are some examples of oscillators which don't require transistors or vacuum tubes?
>
> So far I found relay oscillators and the Pearson-Anson oscillator.
>
> Does the Pearson-Anson oscillator require a high-voltage neon lamp, or would it work on LEDs as well?
> https://en.wikipedia.org/wiki/Pearson%E2%80%93Anson_effect

needs a gas discharge tube, spark gap, sidactor, tunnel diode, PUT, or
UJT etc - something with a negative resistance region, LED won't work.

> Relay oscillators look neat too but I don't imagine they would last very long at high frequencies.
> https://www.youtube.com/watch?v=WuG4nOyF99s

tesla coil. (and other spark gap oscillators)

car horn, dc electric bell (I guess these are really relay oscillators)

electric motor

hot-wire (wire heats up due to current and gets longer)
eg: automotive blinker unit

bimetallic (metal changes shape in response to heat from an electric
heat source)
eg: stovetop simmerstat

carbon microphone feedback (I guess this is an accoustically coupled
analogue relay oscillator)



--
Notsodium is mined on the banks of denial.

jurb...@gmail.com

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Oct 18, 2018, 1:41:51 AM10/18/18
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Old style doorbell or buzzer.

Tom Gardner

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Oct 18, 2018, 5:17:26 AM10/18/18
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And, of course, there are a range of purely chemical oscillators
As good a starting point as any is
https://en.wikipedia.org/wiki/Chemical_oscillator

jf...@my-deja.com

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Oct 18, 2018, 8:12:26 PM10/18/18
to
On Wednesday, October 17, 2018 at 7:32:04 PM UTC-7, mrda...@gmail.com wrote:
> Ah ok, thanks. While I was at the university I was under the impression
> that one could create an oscillator with a combination of resistor, inductor
> and capacitor, but now I see most electronic oscillators require a transistor
> of some sort.
>
> Michael
The spin-torque oscillator is magic. It is a thin film structure with nanometer-thick layers of normal conductors, ferromagnetic materials, and antiferromagnetic materials. Apply a dc current, and it continuously produces microwave oscillations. No active gain elements or resonators are required.

Phil Hobbs

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Oct 18, 2018, 8:54:05 PM10/18/18
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There are also Gunn and IMPATT diode microwave oscillators.

John Larkin

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Oct 19, 2018, 12:32:56 AM10/19/18
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Carbon microphone and speaker.

Pendulum clock.

Arc oscillator (once used for broadcast transmission)

Violin.

Clarinet.

Zener diode.

Gunn diode.

Fingernail on blackboard.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

amdx

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Oct 28, 2018, 10:40:55 PM10/28/18
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On 10/17/2018 2:33 PM, mrda...@gmail.com wrote:
> Hello,
>
> What are some examples of oscillators which don't require transistors or vacuum tubes?
>
> So far I found relay oscillators and the Pearso There n-Anson oscillator.
>
> Does the Pearson-Anson oscillator require a high-voltage neon lamp, or would it work on LEDs as well?
> https://en.wikipedia.org/wiki/Pearson%E2%80%93Anson_effect
>
> Relay oscillators look neat too but I don't imagine they would last very long at high frequencies.
> https://www.youtube.com/watch?v=WuG4nOyF99s
>
> Thanks,
>
> Michael
>

There used to be signs that used movement to get attention, it could
be as simple as a waving hand. The hand was setup as a pendulum and when
the battery was installed you could give it a push, this would close a
switch, energizing the solenoid and giving the pendulum a kick this
would also open the switch. The pendulum would go through its swing and
then come back and close the switch, repeating the cycle.
I searched but could not fid a sign or a circuit, but I'm sure there is
one somewhere online.
Variation of the relay oscillator.

Mikek

jurb...@gmail.com

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Oct 29, 2018, 8:34:29 AM10/29/18
to
The vibrator in an old car radio. Not only does it oscillate without transistors or tubes, some rectify without diodes. A second set of contacts make for a synchronous rectifier.

jf...@my-deja.com

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Oct 29, 2018, 10:13:24 AM10/29/18
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If you ever opened one, you would find it is basically an electromagnet configured as a buzzer, just like the one you probably built in grade school science or shop class, and just like the one you mentioned a couple weeks ago.

mrda...@gmail.com

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Oct 29, 2018, 1:47:36 PM10/29/18
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On Monday, October 29, 2018 at 5:34:29 AM UTC-7, jurb...@gmail.com wrote:
> The vibrator in an old car radio. Not only does it oscillate without transistors or tubes, some rectify without diodes. A second set of contacts make for a synchronous rectifier.

Amazing!
https://en.wikipedia.org/wiki/Vibrator_(electronic)

How long did they last? A year or so?

Thanks!

Michael

Phil Hobbs

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Oct 29, 2018, 3:38:55 PM10/29/18
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The really fun one was the box with a trap door on top and a big toggle
switch on the front. When you turned on the switch, a motor whirred and
a plastic hand came out of the box, turned the switch off again, then
went back into the box before the motor actually turned off.

I had a piggy bank that worked like that--you put the coin in a shallow
slot with two contacts at the bottom. The coin completed the circuit,
and the hand came out and collected the coin.

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
https://hobbs-eo.com

Jasen Betts

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Oct 29, 2018, 4:01:10 PM10/29/18
to
a car won't last a year if operated continuously: at 60 km/h that would be
half a million kilometers

I had one in my car for a couple of years and never had a problem.
that was maybe 400 operating hours.

I expect they got a couple of thousand hours out of those units about
the same as we see quoted for cheap electrolytic capacitors and LEDs.



--
When I tried casting out nines I made a hash of it.

mrda...@gmail.com

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Oct 29, 2018, 4:39:47 PM10/29/18
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2000 hours! That durable, huh!

jurb...@gmail.com

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Oct 29, 2018, 9:51:57 PM10/29/18
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>"and just like the one you mentioned a couple weeks ago. "

Yeah but I forgot about the synchronous rectifier part. Not only no transistor or tubes, no diodes either of any "state".

Cursitor Doom

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Oct 30, 2018, 2:30:11 PM10/30/18
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On Sun, 28 Oct 2018 21:40:50 -0500, amdx wrote:

> There used to be signs that used movement to get attention, it could
> be as simple as a waving hand. The hand was setup as a pendulum and when
> the battery was installed you could give it a push, this would close a
> switch, energizing the solenoid and giving the pendulum a kick this
> would also open the switch. The pendulum would go through its swing and
> then come back and close the switch, repeating the cycle.

Sounds grossly inefficient. I'm reminded of those Chinese cat things with
the waving paw. They seem to have got battery life down to a fine art;
must be using a 'joule thief' or some variant thereof I would imagine.




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protocols constitutes acceptance of this condition.

default

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Oct 31, 2018, 12:26:45 PM10/31/18
to
On Tue, 30 Oct 2018 18:30:08 -0000 (UTC), Cursitor Doom
<cu...@notformail.com> wrote:

>On Sun, 28 Oct 2018 21:40:50 -0500, amdx wrote:
>
>> There used to be signs that used movement to get attention, it could
>> be as simple as a waving hand. The hand was setup as a pendulum and when
>> the battery was installed you could give it a push, this would close a
>> switch, energizing the solenoid and giving the pendulum a kick this
>> would also open the switch. The pendulum would go through its swing and
>> then come back and close the switch, repeating the cycle.
>
>Sounds grossly inefficient. I'm reminded of those Chinese cat things with
>the waving paw. They seem to have got battery life down to a fine art;
>must be using a 'joule thief' or some variant thereof I would imagine.

The so-called joule thief is what was called a blocking oscillator
back in the days of vacuum tubes and you could find one in every tube
type TV. The flyback pulse produces a high voltage because the
tube/transistor is cut off abruptly, and the collapsing field produces
a voltage spike.

Those moving display gizmos were neat, I used to play with them as a
kid. A single D battery or pair of them could keep the thing swinging
for a week or two. The magnet was on a half-circle of wire and
suspended so it would pass through the coil, working a leaf-switch of
a couple of phosphor bronze springs that would repel the magnet as it
passed the midpoint. What is impressive was the length of time they's
keep working - particularly with the zinc carbon batteries we had in
those days.

Transistors cost money back then too. My first blocking oscillator
using transistors was pulled from a Radio Electronics magazine for a
"sonic shake table" (an interesting gizmo that could make standing
waves in particles of flour in an upturned speaker cone - or mercury
if you happen to have some) When I got tired of playing with it, I
added it to my bicycle for a horn and ran it off the hub mounted
alternator.

Don Kuenz

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Nov 12, 2018, 11:50:24 PM11/12/18
to
default <def...@defaulter.net> wrote:
> On Wed, 17 Oct 2018 12:33:19 -0700 (PDT), mrda...@gmail.com wrote:
>
>>Hello,
>>
>>What are some examples of oscillators which don't require transistors or vacuum tubes?
>>
>>So far I found relay oscillators and the Pearson-Anson oscillator.
>>
>>Does the Pearson-Anson oscillator require a high-voltage neon lamp, or would it work on LEDs as well?
>>https://en.wikipedia.org/wiki/Pearson%E2%80%93Anson_effect
>>
>>Relay oscillators look neat too but I don't imagine they would last very long at high frequencies.
>>https://www.youtube.com/watch?v=WuG4nOyF99s

> When I was in high school I built this rather elaborate relay
> oscillator to dial a pulse type telephone. One relay developed
> pulses, another was rigged as a monostable to time the pulse train to
> dial a particular number. A rotary stepper relay could read the holes
> in cards and cycle through some crude punch cards to dial (worked but
> not well)
>
> Scr's can be made to oscillate, of course unijunctions, some negative
> resistance diodes like tunnel/gunn, electro-mechanical toys using
> magnets and leaf/reed switches or transistors to energize coils,
> old-time magnetic earphones and carbon mikes to develop feedback,
> tuning forks with feedback drivers, propagation delay devices, arc
> lights, early radio transmitters that used motors driving many-pole
> alternators, spark-excited Tesla coils...

Was your high school project an electronic vibrator?

https://en.wikipedia.org/wiki/Vibrator_(electronic)

Thank you, 73,

--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

default

unread,
Nov 13, 2018, 7:42:23 AM11/13/18
to
On Tue, 13 Nov 2018 04:50:22 -0000 (UTC), Don Kuenz <g...@crcomp.net>
wrote:
No but some years later I made a small air pump using a coil driving a
magnet. Other than the heat it developed, it might have made a decent
vibrator (of the sex toy variety).
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