[time-nuts] AM vs PM noise of signal sources

Arnold Tibus arnold.tibus at gmx.de
Sun Jan 7 11:05:14 EST 2018

Am 07.01.2018 um 16:33 schrieb jimlux:
> On 1/6/18 6:12 PM, Dana Whitlow wrote:
>> One point about oscillator design I've not yet seen mentioned is this: 
>> the
>> limiter
>> must not degrade the resonator Q when in action.  Hence, a pair of diodes
>> connected in parallel back to back, across a shunt resonator, would be 
>> a bad
>> thing to do from the perspective of low phase noise. A differential
>> amplifier
>> that limits by running out of current on peaks, driving a shunt 
>> resonator,
>> is
>> a much better way even though one pays a price in having more transistor
>> noise in the circuit.
>> I've long wondered if a very slow AGC might avoid the nonlinear 
>> mechanisms
>> issue except, of course, for things happening within the AGC loop's
>> bandwidth.
> That's the Wein bridge stabilized by a light bulb, popularized by Messrs 
> Hewlett and Packard a while ago.
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Hello everybody, excuse me please,

but I see quite often mentioned the 'Wein bridge'. (Wein in german is 
'vino' or 'wine' ;-)
Not of real technical importance, but shouldn't this not be correctly 
called a 'Wien bridge'?
As I know that this tricky circuit was developed by Max Wien in 1891.
Max Karl Werner Wien was a German physicist and the director of the 
Institute of Physics at the University of Jena at that time.
  (sorry, I am a nut ;-)  )

My best wishes for 2018 to everybody,

Arnold, DK2WT

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