On a sunny day (Sat, 20 Jul 2013 20:53:24 +0300) it happened Tauno Voipio
Is it really American to give every freaking circuit a name?
I do not even remember those names.
....
Jan - then you do not know the Vacker oscillator either ;-)
E.g. Why do engines have names V8, Stirling Engine, Jet Engine and so on.
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My presumption is that all variable LC oscillators ought to be using
Vacker design to correctly maintain oscillation combined with low
feedback and amplitude - over a small - or especially wide frequency
variation.
With all the electronic made in the last 30 years, why has no one found
this design (again)? Why has no one been educated about this oscillator?
The Vackar VFO oscillator:
http://www.qsl.net/va3diw/vackar.html
Quote: "...
Jiri Vackar [Jiřà Vackář] invented his VFO oscillator during late 40s.
It is probably the most stable VFO oscillator known. Thanks George!
....
The frequency tuning range is above 2.5, not observable in any other
type of oscillator. The Coupling ratio is fixed; typical range is 1:4 up
to 1:9.
[]
The tuning is provided independently of coupling. Transistor's
parametric variables are isolated from the resonator. The transistor
input is not overloaded as Clapp or other circuits.
....
The stability is close to XO.
....
Ordinary oscillator has poor tuning range, the output voltage swing is
unstable, and the frequency stability is poor as well. The industry
tries hard to make its sale pitch, to replace single oscillator with 50
ICs, digital dividers, approximation registers, thermostats, and other
junk. Now what?
....
The best regulator of all times is maybe the LM723. [really
]
....
The VFO is better solution than the AD9850,AD9891 DDS - direct digital
synthesizer chip.
....
Do you want to spend time calling around and dealing with ten weeks lead
time? An old cap from an old TV tuner can help to solve your problem.
The treasures are around you.
...."
Scanning of original paper:
http://web.archive.org/web/20120219062848/n1ekv.org/Oscillators/Vackar_wholepaper.pdf
http://n1ekv.org/Oscillators/Vackar_wholepaper.pdf
http://n1ekv.org/Oscillators/2003 MUD resources.htm
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A regenerative receiver ought to be easier to tune with Vacker design.
Why has anyone not thought of that - assuming no one did - please
correct me if I am wrong.
Glenn