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RF CV to CC Converter?

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carpenter

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Yesterday I read a description of some RF construction in which it is on one side
CV PS freqency over 10MHz and this power variable load (estimated 40 ohm and decreasing to 5 ohm) and between the source and the load is cucruits described as CV to CC conventer.
Technically it is a simple L C circuit see on Picture

Do you have any idea how it works?

CVCC.png
 

author directly states "stage constitutes the phase shift network of the CV to CC"
 

It's an impedance matching circuit, not a "CV to CC converter". It can't achieve constant current over varying load resistance, at best same current for two different loads.
 

It also feels like that, but in documentation is block diagram any as
BS.png

in the description and the detailed scheme then follows
RF PA - standard PA with two MOSFET
IMC - impedance matchng circuitr with L C for matching Z1 output stage PA to Z2 probably 50 Ohm
LPF - 5th L C filter for produce pure sinus
CVCC - technical LC see first post. The documentation says
1. .... he circuit is primarily a constant voltage regulator which uses the CVCC to produce a constant current.
2. .... a constant voltage to constant current circuit is the subject of the invention number xyz (Unfortunately, this is an invention from the 70's and cannot be traced online)
3. output from LPF is supplied to the input stage of the CVCC which stage constitutes the phase shift network of the CVCC and convert constant voltage to constant current

The pig knows it.

The load is in real complex variable impedance
 

I couldn't sleep, and I sketched the part behind the circuit called CVCC
- sine over 10MHz is input to the CVCC circuit (from LPF)
- then it is L 400nH torid T68 + C 100pF Silver mica and N connector
On coaxial line is C pro DC blocking with small L for proof small DC current (load detection I thing not important to function)
Load have prevailing L 3uH decreasing to 1 small R about 0,3 Ohm and parasitic C .
Impedance load on working frequency is about 42 ohm and decreasing (from the principle of function) and yes something (by the author and his description) at least partially and in a small time section causes the current to not rise at voltage constant with decreasing R.
In a longer time horizon, the voltage is reduced and thus the load change is compensated, but this regulation is in the order of hundreds of ms.

CVCC.png
 

This sounds all wrong (or at least hiding important information). Impedance of 3 uH at 10 MHz is > 185 ohm, there's no time constant in a 100 ms range in this circuit.
 

OK real not not rounded measurement data
On 100kHz I on one load measure 2,76uH and her is impedance measurement on frequency 10,5MHz 44,21 Ohm.
100ms is secondary control and has no effect on it.
if the load impedance is changed (DECREASE) for less than 100ms, the device behaves as a constant current source not a constant voltage.
the author in the description claims that it does a CVCC circuit and I do not know how?

imp.png
 

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