Jeffree cell and scophony

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Jeffree cell and scophony

Postby theo » Thu Sep 09, 2021 7:16 am

On our NBTV site I cannot find any information - or other people - how had done some experiments, on and with a ‘Jeffree Cell’ originally used in the (mechanical) video projector from Scophony. The fact that you can modulate RF frequency’s and thereby make an optical modulation of a light beam, sounds very interesting. Is there anybody out there, how has some experience with the phenomena? Used crystal's ???
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Re: Jeffree cell and scophony

Postby Harry Dalek » Sat Sep 11, 2021 4:59 pm

theo wrote:On our NBTV site I cannot find any information - or other people - how had done some experiments, on and with a ‘Jeffree Cell’ originally used in the (mechanical) video projector from Scophony. The fact that you can modulate RF frequency’s and thereby make an optical modulation of a light beam, sounds very interesting. Is there anybody out there, how has some experience with the phenomena? Used crystal's ???


Did not look hard enough :wink:
viewtopic.php?f=12&t=2710&hilit=jeffree+cell

Well i found a problem with the crystal idea resonating not mentioned in any thing i read and that is heat ! your tank would soon boil away the crystal fiction in the liquid is a big problem ,i rather kerr cell ,i found a clipping i posted up in off topics where it used cane sugar which i never heard of before .i will see if i can find the link .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: Jeffree cell and scophony

Postby Harry Dalek » Sat Sep 11, 2021 4:59 pm

theo wrote:On our NBTV site I cannot find any information - or other people - how had done some experiments, on and with a ‘Jeffree Cell’ originally used in the (mechanical) video projector from Scophony. The fact that you can modulate RF frequency’s and thereby make an optical modulation of a light beam, sounds very interesting. Is there anybody out there, how has some experience with the phenomena? Used crystal's ???


Did not look hard enough :wink:
viewtopic.php?f=12&t=2710&hilit=jeffree+cell

Well i found a problem with the crystal idea resonating not mentioned in any thing i read and that is heat ! your tank would soon boil away the crystal fiction in the liquid is a big problem ,i rather kerr cell ,i found a clipping i posted up in off topics where it used cane sugar which i never heard of before .i will see if i can find the link .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Harry Dalek
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Re: Jeffree cell and scophony

Postby Harry Dalek » Sat Sep 11, 2021 5:01 pm

The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: Jeffree cell and scophony

Postby theo » Wed Sep 22, 2021 11:29 pm

Hello Harry. Thank you for the response (I am not looking every day on this site). Nice to see that I am not alone in my interests. Strangely I have this first link, although the content, found elsewhere on the net??? But thanks anyway. As I understand, you did some experiments on this desing and prefere the Kerr Cel. Strange, as I understand correctly, the Jeffree must be far supperir to the Kerr. Your experiments looks very nice! As I understand correctly, you never build a complete cell and tested only, the crystal’s? The delay experiment looks promising and will look in to that myself. I used that delay line for something completely different. Look at; http://www.theofaberalmere.nl/assets/delayline-vco.pdf design is published in electronics magazines unfortinaly only in Dutch. I always thought that the delay line itself, was glass and reflected the 4.43 wave. The transducers (crystal like) where mounted on the edges. When I tested the several delay lines, I found the bandwith rather large. More that 1MHz. And that must be, otherwise the color-signal will be limited. But that’s an other story all together. Did you ever manage to build a working cel, Kerr or Jeffree???
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Re: Jeffree cell and scophony

Postby Harry Dalek » Thu Sep 23, 2021 4:08 pm

theo wrote:Hello Harry. Thank you for the response (I am not looking every day on this site). Nice to see that I am not alone in my interests. Strangely I have this first link, although the content, found elsewhere on the net??? But thanks anyway.


I did use Chris longs web site on super sonic sound for the valve oscillator circuit may be it was that ,its easy to make .

Yes i wanted to see if i could get the crystal idea to work at first it sounds doable but vibrating the crystal to a point where its useable cause's heat .

As I understand, you did some experiments on this desing and prefere the Kerr Cel.


I think the kerr cell would be a better idea i was thinking the Jeffree was at the start but it is mechanical so this means friction heat only due to the levels the crystal has to work at ,not not some thing you would notice using a crystal for a oscillator but to move a mass is a different story ,it of cause worked in the past ,but for me i had a heating of the liquid problem .

Strange, as I understand correctly, the Jeffree must be far supperir to the Kerr.


I was thinking that too sounds cleaner a better idea may be i was over doing it with the levels to the crystal ? ,don't let me put you off if you want to try it ,it all got a little to messy for me to be useable .

Your experiments looks very nice! As I understand correctly, you never build a complete cell and tested only, the crystal’s?

Only what was shown i wanted to to see if i could see the effect in a liquid and if it could effect light levels

The delay experiment looks promising and will look in to that myself.


Yes do have a go its messy but fun experiments ...if using chris longs 30s magazine oscillator design you need a rather large crystal ...there are lower frequency versions used in vapor machines Ultrasonic Air Humidifier crystals i have forgotten the correct name its in my posts .

I used that delay line for something completely different. Look at; http://www.theofaberalmere.nl/assets/delayline-vco.pdf design is published in electronics magazines unfortinaly only in Dutch. I always thought that the delay line itself, was glass and reflected the 4.43 wave. The transducers (crystal like) where mounted on the edges. When I tested the several delay lines, I found the bandwith rather large. More that 1MHz. And that must be, otherwise the color-signal will be limited. But that’s an other story all together. Did you ever manage to build a working cel, Kerr or Jeffree???

[/quote]

viewtopic.php?f=1&t=2477&p=22679&hilit=kerr+cell#p22679

OH that reminds me you will find this of interest ! a delay line and modulation into a liquid

viewtopic.php?f=1&t=2709&hilit=delay+line

Back of my mind the Kerr cell with cane sugar sounds much safer than benzene to try ! ,i was looking to into where i could buy the cane sugar liquid and it is on Amazon ...just in my head at the moment on the to do list !
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Harry Dalek
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Re: Jeffree cell and scophony

Postby theo » Sat Sep 25, 2021 5:24 am

Harry, again thanks for de response and link’s. I will look into maters and don’t think that heat will be a problem. One side of the transducer will be in the liquid. The Kerr cell is promising, because simple polaroid filters are now day’s available (camera shop). But the use of dangers liquids sound’s less attractive. Keep you posted. First, I have to finish a video program. It will be aired very soon and a lot of edit and researds, still has to be done.
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Re: Jeffree cell and scophony

Postby Harry Dalek » Sat Sep 25, 2021 12:28 pm

theo wrote:Harry, again thanks for de response and link’s. I will look into maters and don’t think that heat will be a problem. One side of the transducer will be in the liquid. The Kerr cell is promising, because simple polaroid filters are now day’s available (camera shop). But the use of dangers liquids sound’s less attractive. Keep you posted. First, I have to finish a video program. It will be aired very soon and a lot of edit and researds, still has to be done.



Well it obviously worked for scophony ,i just think they would of had to every now and then refill the tank if it was open with a stopper lid ? every thing on the cell is in that link working on video modulation in liquids .
Working on the crystal version you have to scale it the tank to the crystals size . do show results when you experiment success or failure are both important .
i mentioned the cane sugar Kerr cell as i had never seen it used with this liquid and it sounds safe .
So good luck just ask if you get stuck
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Harry Dalek
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