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From: Jan Panteltje <alien@comet.invalid>
Newsgroups: sci.electronics.design
Subject: Re: noise question
Date: Tue, 16 Jul 2024 05:42:51 GMT
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On a sunny day (Mon, 15 Jul 2024 09:15:45 -0700) it happened john larkin
<jlarkin_highland_tech> wrote in <ikia9jhlgdclsb40267f6potnk6hec6ue9@4ax.com>:

>On Mon, 15 Jul 2024 14:40:44 -0000 (UTC), Dan Purgert <dan@djph.net>
>wrote:
>
>>On 2024-07-15, john larkin wrote:
>>> Does a negative 50-ohm resistor make as much noise as a regular 50 ohm
>>> resistor?
>>
>>Yes, just inverted?
>>
>>(also, "negative" resistance?)
>
>Sure. I = -E/R.
>
>Connect that to a battery, and it charges the battery. Across a
>capacitor, you get an exponentially increasing voltage.
>
>That works in Spice.

I was thinking about this last night (so beware)
The only 2 pole negative resistors I know about are tunnel diodes.

For 50 Ohms if you could bias one so an increase of 50 mV leads to a 1 mA decrease in current that would be -50 Ohms?
No idea if the curve allows that,
And then measure the noise with some of your super test equipment.
If 500 Ohms divide by 10

No idea if this makes sense, have not had my hands on tunnel diodes for many decades.
Those were still on ebay some years ago,
Got some UJTs to make nice stable pulse generators....

For what it is worth mamaticians!

EL Tee Spice, ..mostly use salt, pepper and Chili.
Oh and sugar...
oops the list is longer

Too much of Spice is . too much not good 4 U