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Tunnel diode based low frequency 1/f generator

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researcher

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I have already posted a question previously on 1/f generator ideas in the ELF band. (https://www.electro-tech-online.com/threads/1-f-pink-noise-generator-in-the-elf-band.145101/) At that time I got many useful comments and suggestions. I am very grateful for that.

Now I have a more specific question.
I found some old documents about the 1/f noise properties of tunnel diodes. (**broken link removed**) I think tunnel diode would be a good source of low frequency 1/f noise for my experiments.

I would like to ask your help to design a suitable 1/f generator circuit using a tunnel diode as a noise source. I have this Japanese tunnel diodes:
http://www.americanmicrosemi.com/information/spec/?ss_pn=1S1763

Can anybody suggest a schematic using this tunnel diode?

Thank you in advance!

G.
 
It would appear that you bias the tunnel diode at a low current with a resistor and then amplify the noise of the diode with a low frequency amplifier to get the 1/f noise.
The optimum bias current is likely best determined by experiment.
 
Yes, this is exactly what I want to do.
Can anybody provide a schematic about this arrangement?
(I am not an electrical engineer, however I have a good skill to assemble any circuit if I have a proper schematic)

Thanks.
 
How low in frequency do you want to go?
 
Well, as low as technically possible.

But if we consider the general timescale of the homeostatic control in human physiology which is approximately 6 minutes, it gives ~0.003 Hz.
I am not sure what doable technically is...
 
Dear Alec,

Have you read carefully my original question?

Do you think I would waste my time here if a simple google search would provide the suitable information I need?

Thanks.
 
Post deleted.
 
Here's my rough shot at what your circuit might look like.
I use an op amp in the transimpedance mode to convert the tunnel diode noise current to voltage.
The op amp can be just about any low input bias current J-FET or MOSFET type.

The op amp should be powered by plus and minus supplies.
If you only have one supply, then you can bias the op amp plus input at 1/2 the supply volage using two 1kΩ resistors in series between the +V and ground. If you do that, then the op amp output needs to have a capacitor in series to block the DC voltage.
Also the polarity of C1 would have to be reversed.

You likely will need another amp at the output for further signal amplification, depending upon your requirements.

The resistor values are just a starting point and you may have to modify them when you see how the circuit operates.
R2 controls the circuit voltage gain.

V1 should be a variable 10V DC supply.
Diode Noise Amp.PNG
 
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Dear Crutschow,

Thank you very much for this schematic. I will try the suggested setup.
Note, that the circuit is just a basic starting point.
Testing will determine what might have to be modified to get the signal you want.
For example you may have to roll-off (low-pass filter) the higher frequency noise if that is unwanted or saturates the following circuitry.
Post your results here.
 
My 2penneth.
Build the circuit in an ally box, with 10mr feedback resistance the circuit is likely to pick up electrical noise around it.
You could replace r1 with a 10k, or 47k pot to adjust the o/p, a while back I took an interest in vlf submarine radio (16hz), there is a program for the pc, it works with the pc's sound card but its basically an elf spectrum analyser, handy for checking a elf noise generator, I cant remeber how they got around the low frequency roll off of a pc's sound card.
 
Thank you very much for these useful comments.

Of course, I will post the results here.

By the way, what was this softvare you (dr pepper) mentioned in your comment? I am really very interested in it.

There is a nice portal for VLF detection: http://www.vlf.it
They suggest some sound card based spectum analysis software as well.
 
I think it was argus, which after a google search turns out to be a professional package written by rhode & schwarze, there must be a demo or student version as mine was free and it wasnt bootleg.
 
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