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Tracking down a cathode noise reference - Philips Journal of Research circa 1967

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bondini

bondini

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#1
This is a request to members who may have copies of Philips' research publications from the 1960s. I have a quote (below) attributed to "Hooge, F.N., 1967, in the Philips Journal of Research, Volume 34, p.99" which reads:

The [shot noise] expression holds quite accurately for tubes in which the cathode is made of either clean or thoriated tungsten…When an oxide-coated cathode is used, fluctuations of a larger magnitude are superimposed on the true shot effect. These fluctuations are inappreciable above about 10 [kHz] but increase rapidly in magnitude toward the lower frequencies. They also increase with current at a faster rate than the shot effect fluctuations. This disturbance has been ascribed to a state of flux and change in the activating material on the surface of the cathode, and the phenomenon has been called the “flicker effect” (from the analogy of a flickering candle).​

I have a long-standing interest in noise in vacuum tubes and would like to read the original article. I have searched widely (including in the Pearl Hi-Fi archive) without success (I searched the Philips Journals, Research Reports and Supplements in case the journal reference is mistaken). I would be grateful if anyone could point me in the right direction to find a copy.

Many thanks!
 
#2
Don't have copies of the Philips Journals, but the quotation seems to reflect 1960s thinking about excess noises. Better than pre-War RDH4 confusion of various terms (in respect to modern terms) but not modern in the sense of the larger (but still mysterious) model of 1/f noises.

Until a couple years ago, excellent and almost intuitive answers to questions about these topics were available right here in diyAudio tubes/valves from member DF96, but he's gone and we're poorer for the loss. RIP.

All good fortune,
Chris
 
#3
Pity it's not in the Philips Technical Review, those can be found online at the NVHR site (nvhr.nl). The library of the Delft university has the Philips Journal of Research, but only from 1978 to 1998. Is there a university library in your neighbourhood that may have more of them?
 
#4
Are you sure it's not

Philips research reports : a journal of theoretical and experimental research in physics chemistry and allied fields​


The Delft university library has those from 1945/1946 to 1977 (vol. 1 to vol. 32)

Edit: 1967 would then be volume 22 rather than 34, so it doesn't add up.

Apologies for the bold letters, I copied something in bold letters and now I can't get rid of them.
 
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#5
Thanks, Marcel - that's a new lead to follow and I'll go down the road to colleagues at the Australian National University for a bit of help.

Chris - Hooge's published research includes a lot on 1/f noise in semi-conductors - bitten by the bug, I suspect. 🙂
 
#10
bondini said:
This is a request to members who may have copies of Philips' research publications from the 1960s. I have a quote (below) attributed to "Hooge, F.N., 1967, in the Philips Journal of Research, Volume 34, p.99" which reads:

The [shot noise] expression holds quite accurately for tubes in which the cathode is made of either clean or thoriated tungsten…When an oxide-coated cathode is used, fluctuations of a larger magnitude are superimposed on the true shot effect. These fluctuations are inappreciable above about 10 [kHz] but increase rapidly in magnitude toward the lower frequencies. They also increase with current at a faster rate than the shot effect fluctuations. This disturbance has been ascribed to a state of flux and change in the activating material on the surface of the cathode, and the phenomenon has been called the “flicker effect” (from the analogy of a flickering candle).​

I have a long-standing interest in noise in vacuum tubes and would like to read the original article. I have searched widely (including in the Pearl Hi-Fi archive) without success (I searched the Philips Journals, Research Reports and Supplements in case the journal reference is mistaken). I would be grateful if anyone could point me in the right direction to find a copy.

Many thanks!
Click to expand...
Those words appear in "The Limits of Amplification" by Johnson and Llewellyn, 1934:

https://archive.org/details/bell00systemtechniamvol14errich/page/88/mode/2up
 
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