Author Topic: My pll circuit  (Read 24553 times)

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Re: My pll circuit
« Reply #56 on: September 28, 2012, 17:41:19 pm »
where you want,, whatever capacitor will form a resonant tank.... in series or parallel... 

I guess with the vic the chokes become the capacitance like---

Sorry, not quite following.  Putting just any capacitor in line with any coil will create resonance signals based on the induction and capacitance of the coil and capacitor's values.  It won't necessarily match the resonance of the VIC.

TS

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Re: My pll circuit
« Reply #57 on: September 28, 2012, 22:44:58 pm »
I talking about working on the pulse indicator circuit to get it working... what you do later is another thing...

if you have only primary and feedback coil no reonance should result ...than adding a capacitor wherever you want will make of it a tuned circuit won't... 

sebosfato

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Re: My pll circuit
« Reply #58 on: September 30, 2012, 21:16:00 pm »
probably something like that or less...

at least this makes sense... you can discriminate the frequencies by its signal level... otherwise it will try to tune to whatever signal it receives...

Stan called Resonance feedback, pulse indicator, meaning that it indicates where there is resonance...

the lock in led should light than only when lock to resonance...

I always had a feeling it should be that way, until Tony's diagram said it should be the same.  Not to mention that in all of Meyers diagrams that the feedback coil is always demonstrated as being smaller.

TS

I've put a 5k resistor in line with the feedback coil that is the same length as the primary.  It locks resonance much better now.

TS

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Re: My pll circuit
« Reply #59 on: September 30, 2012, 22:38:08 pm »
My experience so far is the larger the ratio of turns on the secondary, the lower the resonant frequency.  At 20:1 my resonant frequency drops to about 11Hz.

TS

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Re: My pll circuit
« Reply #60 on: October 01, 2012, 12:06:56 pm »
Wow great info... could you explain a little further?

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Re: My pll circuit
« Reply #61 on: October 01, 2012, 12:42:09 pm »
Wow great info... could you explain a little further?

I'm working on some numbers.  I'll expand further when I can.   I was a little puzzled when my first step up locked in at 500Hz and expected the 20:1 to lock in with a higher frequency.  Even though it is still scanning with a frequency in the kHz range, the lock in frequency when probing the cell was still only 11Hz.

TS

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Re: My pll circuit
« Reply #62 on: October 01, 2012, 17:21:06 pm »
Wow great info... could you explain a little further?

I'm working on some numbers.  I'll expand further when I can.   I was a little puzzled when my first step up locked in at 500Hz and expected the 20:1 to lock in with a higher frequency.  Even though it is still scanning with a frequency in the kHz range, the lock in frequency when probing the cell was still only 11Hz.

TS

In a way, it actually makes sense.  Since it it will take longer to charge and discharge a larger secondary than a smaller one.   

Actually, I was in error.  I was forgetting the fact the LC is tuned to resonance based on capacitor and inductor values.  Obviously, by the size of my cell, the higher number of turns I have done on my secondary necessitate a lower resonant frequency.  If I want a higher frequency, I need to lower the number of turns appropriately to match the capacitance of my cell.

That means I need a smaller secondary and even smaller primary if I want to step up the voltage. 

TS
« Last Edit: October 01, 2012, 23:35:39 pm by timeshell »

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Re: My pll circuit
« Reply #63 on: October 02, 2012, 04:43:59 am »
Well done, hope you keep coming with more news.. i constructed today a new pll circuit, i added two more 1/10 to achieve lower freqs... i need to buy a new soldering iron i destructed mine while trying to change the point. i found it could be a good resistive choke if needed... just an idea...