Busy with the 4046 to try to find the self resonance frequency from a L/C combination and lock that frequency to get maximum output.

What I did:
By selecting R1 and C1 create Fc and with R1 make pin11 2.5 Volt
The Loop filter for PC2 on pin 13 has a 90 degree phase difference to lock better before the signal goto VCOin

What is the result:
Put power on the IC I see the swing van the output frequency in the adjusted range
With the electronics behind it I see the Sine Wave from the L/C resonance set vary in height but can not lock to a the exact resonance frequency as there is for now no input on pin 14 (Sigin)

I tried many ways to get a suitable signal for this input with using a input coil with a winding on the output L./C coil.
Using a external square wave generator the lock appear on each frequency within the specified range

On this way I could find the resonance frequency resulting in a larger Sinewave output

Is there a way to use the pll on this way as the applied frequency is the same as the feedback frequency?
Or can I modify the input (please help with that) for getting the right frequency

Your help and thoughts will be appreciated

With friendly greetings,

GentleRV

 

Please post a schematic.

 

Hello,

What is the level of the signal on pin 14?
For the HEF version this is given:

For the CD version this is given:


Bertus

 

Typically 4046 is used to solve the medicinal Mishin generator (coil) tuning problem. Typical circuit to use it is at following circuit page in right lowest corner. https://altenergy4u.ru/wp-content/uploads/2016/05/Gen-sean.ФАПЧ.v01-1024x724.jpg

And here similar about resonance finding at induction heater http://storage.flyback.org.ru/files/3243_1321217649.jpg_142.jpg
P.S.: My State is well suspiciously double checking all with .ru originating and found these circuits are completely virus-free. For a while.

 

Hello,

What is the level of the signal on pin 14?
For the HEF version this is given:
View attachment 310318
For the CD version this is given:
View attachment 310319

Bertus

I found out that the signal level, using a capacitor is series with the pin 14, can be very low and still the PLL locks then I am talking about 1-2 millivolt.
The capacitor is there to het 2.5 Volt on this pin and around that voltage the AC signal can lock the PLL

 

Typically 4046 is used to solve the medicinal Mishin generator (coil) tuning problem. Typical circuit to use it is at following circuit page in right lowest corner. https://altenergy4u.ru/wp-content/uploads/2016/05/Gen-sean.ФАПЧ.v01-1024x724.jpg

And here similar about resonance finding at induction heater http://storage.flyback.org.ru/files/3243_1321217649.jpg_142.jpg
P.S.: My State is well suspiciously double checking all with .ru originating and found these circuits are completely virus-free. For a while.

Thank you so much, will study the schematics and if needed come back to you

 

Using a PLL device is generally not the way to determine an unknown resonant frequency. In fact, I see no way it could be used for that unless an accurately calibrated frequency source is also available.
The standard procedure is to feed the resonant circuit with a variable frequency signal through a 10K resistor while monitoring the voltage across the circuit with an AC voltmeter. The voltage will rise to a peak at the resonant frequency.
Another option is to use a "grid dip meter"
The description of the attempt using a CD4046PLL IC makes no sense to me whatsoever.