Page 1 of 5

The Jeffree Cell

PostPosted: Sat Feb 09, 2019 1:21 am
by Harry Dalek
I started a new topic as its a bit off what i was doing and i have been reading up on the idea of the cell getting my head around the beast of a thing and it has my interest for a while i suppose ...
I can see now the ultrasonic idea really needs to take place for this idea and as Gary mentioned rightly ,might give an experiment or 2 a go ..
It must be possible that the crystal works still by touching the liquid i would of thought a crystal touching the mass would stop working now that's an experiment to try and see what happens to the crystal and its frequency ...reading Chris longs page on the cell he was saying that the larger vintage crystals would be some thing to use ....which i have handy if i can get the case off without braking it .
download.png (2.62 KiB) Viewed 8635 times

I came across this video on how they made crystals back in the 40's amazing the amount of work to make one ,i would not like the job the girl has x raying the crystal to change its frequency a touch all day ...need danger money for that job !
I found the early testing of the crystals interesting as as they are held done flat with a light weight as the second connection then tested i would again of thought this would stop oscillation ..
s00031_m.jpg (19.17 KiB) Viewed 8624 times

Re: The Jeffree Cell

PostPosted: Sat Feb 09, 2019 2:59 pm
by Harry Dalek
I had some time today to see if the idea of using a vintage crystal can go any where here .
Picked 4433.619 mhz i had handy to sacrifice for this test...

First test was see if the crystal works after being cut out of the can seems ok here touching the sides of the quartz didn't top it oscillating

i wanted to see next wiring it via a distance from the oscillator circuit had any effect but the crystal still worked ...

Next was put a drop of water on the center connection and oscillation stopped via the crystal .


i dried it off next test i placed it in its socket and it took off again tried the water test again with a drop a repeat but a bit more careful this time with the amount ...

Again oscillation stopped dried it off again and did the same test with oil but same result crystal stopped

Next i knew touching it it wasn't all that fussy and still oscillated so i placed a layer of plastic and did the oil test twice even tried 4 times the amount on it and no effect the crystal keeps on oscillating.
So i think from these tests the crystal can not come in contact with (these liquids any way) i will try the Glycerine Quartz is non-porous so can't be that a bit of a head scratch really ..i only tried on side may be that it was the side where the frequency comes out of that connection.

Re: The Jeffree Cell

PostPosted: Sat Feb 09, 2019 7:31 pm
by gary
Yes, that's what I had had in mind Harry.

Building a Jeffree Cell is something I have always wanted to have a crack at but had never found a source for the quartz crystal.
Although you have an older, and therefore larger, version there I am not sure if it would be large enough (although I have always thought that a miniature version would be possible), at least to produce something like that detailed on the bluehaze site.

I will be watching your progress with great interest.

PS. Thanks for that link on quartz crystal making - very interesting indeed.

Re: The Jeffree Cell

PostPosted: Sat Feb 09, 2019 9:08 pm
by Harry Dalek
gary wrote:Yes, that's what I had had in mind Harry.

Yes sorry Gary reading bits on the jeffree cell it is complex in what it can do just looking into it out of interest if it can go any where or any thing i can try .

Building a Jeffree Cell is something I have always wanted to have a crack at but had never found a source for the quartz crystal.

One or 2 on the forum also have looked into it in the past... i know Chris long is interested i may have a chat with him on it when he comes back from NZ.
Trying to cut one if you can get the Quartz looking at that video i think i would have no hope ,i suppose stuck with experimenting on what we have handy these days ..i am pleased your interested do experiment if you can if you can get hold of something ..may be you could do it with the cnc ! if you could get a crystal least you know how its done to get a ruff cut to work ..

Something i have read twice in the stuff i have posted up is (the light stop) used in a version of it , which i think it means the lens that focuses the light to the cell hits a black spot on the cell far side a circle of ink indian ink its mentioned in one , so no light passed the cell until there's an ultrasonic signal and the light now due to diffraction passes the light stop ...?
I am also seeing another type where as this is not used in this case of a tube with the line of the scan showiing up as light dark bands in the cell pretty and used as the line scan and just focused to the frame scanning mirror i think ..i was not expecting the different ideas on the same idea
I would think a polarized lens glass would do the same thing for the light stop idea...again i think but have not read of it used on a jeffree cell
Screen 00014.jpg
Screen 00014.jpg (31.46 KiB) Viewed 8595 times

Although you have an older, and therefore larger, version there I am not sure if it would be large enough (although I have always thought that a miniature version would be possible), at least to produce something like that detailed on the bluehaze site.

I agree looking at what just a normal transducer does in my past experiment i don't think even it would have the energy to move that liquid enough if it could do a few MHZ....
But may be as you mentioned if its done smaller perhaps a smaller crystal would be in range to do the same thing ..with the size mentioned on chris longs site and looking at the size posted up in the articles on the liquid NBTV transmitting topic i think you do need a bigger crystal unless these things can be vibrated at a high intensity than trying to do it with 5 volts in a solid state circuit ..may i need to look how they did it with the valve circuit voltages and such .
Also since it could be tried for NBTV the crystal could be 5 times less wasn't is 2 mhz band width needed ? and the used a 10 hz crystal used so something around 100khz for nbtv ? so vibrating a crystal with the same circuit would give a more intense vibration at this lower frequency ...i am thinking a bit like the effect you see needed when using higher or lower line rates trying to deflect a crt beam in for line scan deflection its harder to get the deflection line size across the CRT face higher you go in line rate frequency .

Chris long thought a older crystal could do the job i see there are different versions off older crystals i think we would have better luck with that WW2 type i don't think they got any bigger than than or a touch looking at these ....i would of used these if i had them...theres a site that sell the older type interesting in the link below via a link on its page the old army type might be worth trying .

I will be watching your progress with great interest.

I would if it gos any where use a laser instead of the lens focusing idea ...not being able so far to contact the liquid with out the crystal stopping is a problem ..i have to do the experiment again on the other side of the crystal where the side i used was the side where the frequency of the crystal comes out may be that's a no no test the other side i have to wire it out of the socket again cant to it up side down ...
It would effect the crystals frequency but some sort of water proofing on the Crystal side of the liquid would contact...could be a crystal killer so last resort .
Also seeing perhaps a tight membrane between the liquid and the crystal the crystal would work and perhaps transfer the oscillations via the membrane ...thinking out aloud here so who knows which way it go's

PS. Thanks for that link on quartz crystal making - very interesting indeed.

I would not like their jobs some very dangerous ! i found it very interesting too...

Re: The Jeffree Cell

PostPosted: Sun Feb 10, 2019 9:55 am
by Harry Dalek
This might be going over board but i think the answer to getting it to work is some thing like this idea a higher voltage oscillator across the crystal to get it to vibrate in resonance but more intensely....5 volt circuit at the moment isn't going to push any liquid ..
An idea perhaps a 2 crystal idea the first crystal is the oscillator feed it to an amplifier then to the other crystal that has to do the work in resonance with the first crystal ...

Re: The Jeffree Cell

PostPosted: Sun Feb 10, 2019 12:11 pm
by Harry Dalek
I was looking at what Chris long suggested in hes articles the Valve circuit below also has the modulator thinking of ideas here as i am not great on the RF side of things.
reading he's work
It needs to put out depending on the liquid used ...water would be more kero is 32volts RMS minimum 6 times this for 10 mhz...
Might have to go valves i do have some MPSA94 transistors as below data
Type - p-n-p
Collector-Emitter Voltage: -400 V
Collector-Base Voltage: -400 V
Emitter-Base Voltage: -6 V
Collector Current: -0.3 A
Collector Dissipation - 0.625 W
DC Current Gain (hfe) - 50 to 300
Transition Frequency - 50 MHz
i suppose you would have to experiment with the coil windings for the crystal used ..
i noticed there's a W symbol next to the resistors that means watts to me any idea meant here a watt for the resistors `? ... ndMod.html

Re: The Jeffree Cell

PostPosted: Sun Feb 10, 2019 1:25 pm
by Harry Dalek
Another idea on the Quartz crystal side of things ....Gary was mentioning a source of quartz large enough....i think in this time we are living there is just a place to find it ...on the side of the road in old colour tv's the Quartz used in their ultra sonic delay lines the crystal is large ! you could cut it to size ...i am wondering if it will oscillate at the size it is and at what ?


The below video showed not that interesting on its self but showed a ruff idea the thickness of the quartz it looks about the same as the delay line quartz i was thinking it was a lot thinner like today's crystals looks like not .

Re: The Jeffree Cell

PostPosted: Wed Feb 13, 2019 5:21 pm
by Harry Dalek
There were a few things i wanted to try in case i can move further on with this .
I looked into that delay line Quartz ....
As it unchanged i tried to see if the connections on it could be used as in hooking it up to a crystal oscillator see if i could get any thing out of it in this case no more than it acting as a capacitor .
i ended up sanding off the the reflective bumps ( was not easy !)to direct the ultra sonic sound wave across the Quartz and taped some foil either side of the Quartz and again nothing showing me that the crystal was oscillating only acting like a capacitor dielectric .....bit of a bummer putting it another way .
There are a few factors as in the cut of the crystal and thickness ..thicker it is lower the frequency ... the delay line wave go's through it via the side edges instead of flat faces i don't know enough about this ,so putting it aside for now ,i should have better luck with a crystal i know works .

BTW noticed Peter Yanczer made 2 Jeffree cells in the issue 18 1 newsletter just in photo news ,i think by the look of one of them he used a 40s size crystal that you can unscrew from its case that's placed between to brass plates having a guess

I sort of think the amplitude of the signal should make any crystal or more or less vibrate stronger or weaker the volume control a to a loudspeaker .
Quartz must be very strong to as it does this with out shattering ,well i can't do any thing about the crystal side of things at the moment but i can copy the original circuit and see if there is an improvement to the crystals i do have .
Sept38F7.gif (6.46 KiB) Viewed 8516 times

So might be wise to start with the original Triode Jeffree oscillator circuit ,getting some parts together i have a handy ,there was no real information on what Triode tube that was used in the circuit so give that a go ...with a 6SN7GT
6SN7 (1).pdf
(468.07 KiB) Downloaded 336 times

6SN7 (1)-1.jpg

I also buy luck found another circuit similar which may be another one to try ...i think as in the triode version the crystal gos between the coils .

Re: The Jeffree Cell

PostPosted: Thu Feb 14, 2019 4:57 pm
by Harry Dalek
Almost finished jeffree cell oscillator and modulator untested so far

The nob to tune the frequency is a mistake it needs changing due to the circuit both plates of the variable capacitor are live so a metal nob is not a good idea for this circuit need to go plastic .

The variable capacitor is good here as i can add the other sections if i end up needing a higher capacitor ..highest range with one section is 200pf 400 with 2 so on ...i also made the cap to the control grid of the oscillator variable so i have a range here as well ...i can see why the circuit was changed to a pentode and the tuning circuit made safer but for now this is the original i will be testing ...Have to add coil and crystal next and hook it up to a power supply and scope .....i just need 6.3v ac for the heater and 250v ac the recifier bridge filtering is on board....may have to adjust the the DC with a high watt resistor ...may be ....So thats where i am up to today ..

Re: The Jeffree Cell

PostPosted: Fri Feb 15, 2019 2:13 pm
by Harry Dalek
I powered up and tested the oscillator this morning there's a bit of mains ripple on the DC i used a 100uf 400v cap for the filtering but good enough for now testing this today .
I was pleased it worked ..adjusting the coil a bit and i have to neaten this idea up ! it has a range from around 1 to 7 MHZ


The 333 volts for the plate might be a bit high looking at the sine wave on powering up the circuit .

Pushing my analog scope to its limits to display the the sine wave above and also being careful here not to destroy my frequency meter so i used a capacitor but i noticed the signal is so strong the meter just picks it up this close seems very stable to what ever you tune the variable capacitor to ...i was expecting it to only tune in to the crystals resonance or close this has a massive range ,never tried till now using a crystal across a coil and variable capacitor .


The voltage at the coil across the variable capacitor is 230 volts its a bit dangerous to say the least keeping my mind on where my fingers go !
I will have a think about the next step but having the circuit that does the job is a good one for now .


Re: The Jeffree Cell

PostPosted: Sun Feb 17, 2019 2:30 pm
by Harry Dalek
Ok i am more clear now knowing from today's experiments what is needed .
Today i can see the oscillations in the liquid small as it is but viewable ....
To get this to work its not just oscillating a crystal at MHZ range its the intensity needed ,again as amplifier moves less or more air via a speaker the oscillations have to be high enough to see the same effect in this idea as we all know to see the effect in the MHZ range via a liquid it has to be massive ...
Using the valve Triode oscillator across the crystal a very easy way to go for a start.

Apr39F4.jpg (29.32 KiB) Viewed 8455 times

Some of the videos are better than others on the effect i saw but this was the one i took after i first saw an effect on a crystal for the first time .

With the liquid drop tests in the videos ... i would of thought the effects wanted the crystal would be on its made resonance frequency but i think due to any mass on it this changes its resonance frequency thus changing the frequency across the crystal for maximum effect you can tune it in for maximum oscillation.

I am sure temperature and type of liquid and such used also means a change ...

Still no expert on this but seeing the effects today on the liquids with the 4.433 mhz crystal with vintage 50's 60s size i would think on crystal size it would be easier to move a smaller crystal than a larger one with more intensity with the same signal .

A small jeffree cell might very well be possible .

I can only test what i have so i will look into the effect on a smaller one with the same liquid drops test when i have time .
May be the delay line Quartz i have might work now and i can test a larger sized crystal some thing else to look into .

Water seems good bit harder to tune in and it seems to evaporate with the oscillations in a short time a jeffree cell with water i think would need more refilling than an oil version ....but light oils more than likely worse .
i will post this up and convert some more videos to up load

Re: The Jeffree Cell

PostPosted: Sun Feb 17, 2019 3:37 pm
by Harry Dalek
Not easy to film and tune the oscillator at the same time and focus but did my best here to show the other tests today on the crystal oscillating in resonance with the Triode oscillator with Liquid on it's surface .
OH the mess ~ !

Water drop test again below

Olive oil test

Olive oil again on the videos take note on the light reflections

I was not expecting to see a light effect yet or see the oscillations more perhaps the liquid would fly off the crystal or boil away as the water effect after a while so its really great that a simple test as here you can see things are going in the right direction just with a room light at angles

The last video i got the focusing very good on the effects seen ...i don't know about you but i found this so far very interesting !

Re: The Jeffree Cell

PostPosted: Wed Feb 20, 2019 4:47 pm
by Harry Dalek
I have been thinking about increasing the voltage of the oscillations to the crystal what i had was still a bit low but at least it was starting to oscillate the liquid trying a new idea this line in one of the articles i posted in the transmitting NBTV via liquid topic got me thinking
Screen 00005.jpg
Screen 00005.jpg (12.85 KiB) Viewed 8375 times

In that article its circuit used a oscillator to high frequency transformer variable 0 to 3000 volts bit like a tesla coil really might be something to look into but seeing that it should work at much lower voltages i today swapping the center coil direct to the 380 v dc .....think the circuit above was 260v after the 3k resistor to the center coil connection.
Sept38F7.jpg (58.99 KiB) Viewed 8375 times

More like this
Apr39F4.jpg (29.32 KiB) Viewed 8375 times

Now with another 100 volts or so to the crystal sure does oscillate more effect not mentioned in any thing i have read but is logical the vibration the more there is the hotter the crystal gets its warm to hot to the touch with the results shown here.

I will have a look if any of the other videos worked out this afternoon but post this up for now ....That's a water test here

Re: The Jeffree Cell

PostPosted: Wed Feb 20, 2019 5:59 pm
by Harry Dalek
With the crystal resonating below water and olive oil next photo

olive oil

Olive oil test today

Re: The Jeffree Cell

PostPosted: Wed Feb 20, 2019 7:00 pm
by Harry Dalek
May be of interest i also tried Glycerine bit denser than water ..i can see with water olive oil or here Glycerine with the waves passing through the liquid there is a slight barrier to the light as is on full oscillation...
I will have a read up on the light experiments on Chris longs page ,i think i can do away with the optics lens either side of the cell in a version of it and just use a laser .
On the to do list check a smaller crystal and see if it does resonate stronger with less mass i think it should and something i should try .
I am wondering if a tiny cell could be made ...the oscillations in the liquid became less noticeable viewable with more liquid on it even so i think that it could be made size wise so the effect is still noticeable so it would be pretty small if so ...i will have a think about it.
If i still need more power to do this i will have to use a larger valve ...but would the crystal handle it the heat .