#### nav

##### The AM signal and how it works. Carrier and modulation
«  »Last edited
Had a few private messages asking about this and I apologize for my long absence but I've been busy. I have discovered how it works and for the benefit of everyone here and mainly Matt who helped me quite a lot here are some unanswered questions, Matt you were right you do have to prime the system to get the magnetic field.
Any choke whether it be common mode or differential mode choke works on a basic principle. You have two frequencies, a primary frequency you wish to pass through the choke and a secondary frequency you wish to block and that principle is based on Q factors of the coils.

Stan's system is very simple, you prime the two chokes with a low impedance load like any other common mode or differential mode choke system. That load has to be high enough to prime the chokes with thousands of volts trapped in the windings so how does it work? The fuel cell circuit actually passes current (not the tubes themselves) that has a significantly low impedance to create current flow. No choke can EVER work without a primary current flow and that's a fact. Stan Meyer used a resistor in parallel with the cell and it's visible in the pictures, it's about 200 Ohms which is a match of his chokes electrical resistance not their impedance at the carrier frequency. He primes the chokes by running them at a carrier wave frequency and current flows through the resistor like any normal circuit. The chokes are NOT resonant as the carrier frequency, they are resonant at another frequency - the secondary frequency. Any choke system that purges unwanted signals out of a system has to dump those signals to ground through L/C or it burns then up via L/R, in fact some systems use L/C/R together in various ways.

Stan set his mind on L/C but the C wasn't dumped to ground like in normal systems, it was allowed to build on massive caps. The carrier wave primes the chokes into the resistor then Stan introduces a modulation into the fray. The Q factor of the chokes is such that the modulation frequency is at the self resonant frequency of the chokes and those chokes are ringing. If you tune any system based on the Q factor of the chokes then your options are really wide open at that point and you have choices.

But here lies the beauty of this system: During the normal operation of the carrier wave into the resistor, the resistor doesn't actually use high voltage, it uses current and is only voltage rated at it's given ohmic value. The voltage potential in the chokes is 20kv + but the resistor will not in any way recognize that fact, it can only draw voltage based on the Q factor at low impedance and Ohms law. The high voltage potential is actually invisible to the resistor because the high voltage potential is only visible at high impedance!

Stan simply connected his cell to the self resonant frequency of the coils and his positive potential built up on the positive cell because of the diode not allowing a tank circuit to form. Understanding what happens here is not easy by any stretch of the imagination but I'll try to explain it. When the chokes are modulated at their self resonant frequency they will by nature try to form a relationship with ANYTHING connected to them. If it finds that the relationship of a capacitor to be equal in impedance and correct phase it will form a LC or tank circuit with it, if it finds a lower impedance then it will come out of resonance and act just like the carrier wave and induce current. It is all based on WHAT THE CHOKE SEE'S. If there is a diode in the potential tank circuit it cannot take a look in one particular direction only the other but it will take a peek in the direction it can look. In other words it 'pings' it. After it pings it, the normal response is to receive a 'ping' back from another coil or cap and the push pull starts if correct phase and impedance is there. BUT the diode stops the reverse ping and no relationship can be formed at all. Chokes however don't just send one ping, they'll continue to take a peek indefinitely because they have a habit of trying to dump their contents on something else. Stan's system doesn't allow the chokes to understand what they are pinging into, they haven't got a clue because the diode stops reverse pings and the chokes will continue pinging at a very fast rate of knots into a UNKNOWN impedance and phase. It becomes a biased push system and your cell can be any size you like because the chokes can't see them.

So where is everyone going wrong? Basically they are trying to send the modulated frequency into the chokes without the carrier wave and you can't do that. You have to send a carrier wave into a resistive load first then modulate at the resonant frequency of the chokes but timing or phase is also important, the right frequency carrier, it's phase relationship to the parasitic modulations are important so that when you are at resonance the carrier wave cannot interfere with modulations when they ping the cell. This is how it all works my friends and if you don't believe it then build a tiny version of what I've described and you'll see.

Now, the schematic below has another circuit that is totally unnecessary but it is there to explain what the diode does. Q2 driven by the second PWM is totally unnecessary and I've surrounded it in blue. Instead of chopping off the high impedance modulations and stop them entering the 220ohm resister via a diode I've chopped them off with a PWM and Q2, you can see the phase relationship which I've marked. The 220ohm resistor goes exactly where I've placed it on the schematic and the diode does two things, a: it switches between low and high impedance and b: it doesn't allow the cell to ping the chokes and form a tank circuit, instead you end up with the chokes pinging an UNKNOWN impedance indefinitely. The modulation frequencies involved are what ever your chokes are self resonant at and your carrier wave frequency is where the 220ohm resister is happy and enough magnetic field is present in the chokes to provide an high voltage field in them. The beauty of it is that if phased correctly the diode will switch between high and low impedance. The true schematic is also below.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #1,  »
The impedance that the chokes ping into can only be regarded as infinite because there is no response via the diode therefore cell size is totally irrelevant.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #2,  »
The Resistor at R1 presents a very high impedance to the chokes at resonance (modulated frequency) and current cannot pass just like any choke system, the capacitor however is not a dead short like the resistor and cannot complete a circuit and it must rely on a reverse ping to register. The diode stops reverse pings.

#### Gunther Rattay

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #3,  »Last edited
Where do chokes get their energy for high impedance state from when they resonate at secondary frequency (mark and space) and carrier is higher frequency but dc due to the diode?
Mark is always dc pulses instead of continuous current flow. Can magnetic field increase under these conditions?

Despite the diode there is ac voltage over the cell. How comes?
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #4,  »
Maybe it helps to describe the process as a state machine

#### nav

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #5,  »
Quote from Gunther Rattay on September 28th, 10:36 AM
Where do chokes get their energy for high impedance state from when they resonate at secondary frequency (mark and space) and carrier is higher frequency but dc due to the diode?
Mark is always dc pulses instead of continuous current flow. Can magnetic field increase under these conditions?

Despite the diode there is ac voltage over the cell. How comes?
The Resister at R1 (lower picture) presents high impedance to the flow of current at the modulation frequency because like any choke on any series system it will not allow current to pass at it's resonant frequency, The capacitor in the water because the gap between the tubes is so large it also presents a high impedance figure and current will not pass through the water. Ask yourself how a tank circuit works or LC circuit? It works because there is no dissipation of energy due to resistance (high impedance). To start the push pull effect of an LC circuit we must always start with a loaded coil and a high resistance to the flow of current which means the frequency of the coil must be met with an equal resistance to the flow of current. The water fuel cell presents itself as an equal resistance to the flow of current (an high impedance) to the coil and therefore an initial ping of energy (voltage potential) takes place. In a normal LC circuit the capacitor responds by a reverse ping so that the push pull tank circuit will continue but the diode won't allow it. You are left with a situation where the choke is continually trying to create a tank circuit with the fuel cell but the diode won't allow it. This creates a dc bias on the fuel cell because the negative choke isn't allowed to ping the water fuel cell at all because the diode only allows the positive choke to ping the fuel cell.
The reason the chokes are in an high energy state is because they dissipate energy into the resister R1 at the carrier frequency which is low impedance, this energy field is quite substantial which is driving a 220 ohm resistor. When the modulations begin and the chokes begin to resonate at their self resonant frequency the Q factor of the coil changes and the resister R1 becomes high impedance to the flow of current.
The only reason AC is entering the fuel cell on some systems is because there is current flowing through the fuel cell and the diodes ability to stop current in either direction has be compromised. This can only happen if the resister at R1 across the chokes terminals does not present an high enough impedance and the water fuel cell does not present an high enough impedance, Basically your chokes are not self resonant where they need to be where no current can pass through R1 or you have the timing of your modulations so that they become an harmonic of the carrier frequency. They CAN NOT be an harmonic of the carrier frequency!
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #6,  »
If your chokes self resonant frequency is in the harmonic range of the carrier frequency they will merge into low impedance and current will pass across the resister and fuel cell.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #7,  »
You must also understand the workings of the carrier frequency and the chokes. The secondary coil works like any other transformer coil and it steps up the voltage via normal coil operation while under load. The high voltage passes through the chokes and the current passes through the chokes at low impedance which means there is only a small magnetic field present in the chokes. However, because the current at R1 at carrier frequency is high then the inductance in the choke winding's is also high even though the magnetic field is low. When the modulator frequency is passed through the choke, there is enough inductance and voltage present because R1 dictates this. R1 can only use current and voltage in accordance to ohms law, inductance fields are also in accordance with ohms law but the inductance field will only expel energy in accordance with the amount of energy that can possibly be consumed. If you have a system that is capable of 500 amps current and you place a light bulb that is 50 amp, the system will only draw 50 amp not push 500 amps through the bulb. In the same way the chokes have low magnetic field at low impedance but inductance is equal to current draw at R1, then if you switch to high impedance where the magnetic field build up is equal to the higher inductance because R1 is redundant.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #8,  »Last edited
R1 is voltage rated according to the voltage that the secondary coil is passing of perhaps 400v. The amount of current that the resister uses is related to the Q factor of the chokes and the frequency they allow to pass unhindered plus the current value of the resister in accordance to ohms law at carrier frequency. However, all AC current series circuits try to resist the change of the direction of current (inductance). This means that the wires in the chokes are subject to inductance like any other AC circuit. The amount of inductance is related to current draw at R1 and the Q factor of the choke at the carrier frequency. When the Q factor is low enough, the inductance of the choke itself is low but the inductance of the wire is still subject to the value of R1 at carrier frequency. At modulation frequency the Q factor of the choke changes while there is still inductance in the choke winding's caused by R1 at the carrier frequency but R1 becomes redundant and high resistance to the flow of current at modulation frequency (high impedance) takes over. The choke can no longer pass current either through the resister or the cell. But the phase of the choke spikes the cell and tries to form a tank circuit and keeps spiking it while ever the modulation frequency is causing the choke to be self resonant. When a choke becomes self resonant, they act differently, they try and form tank circuits with everything they touch.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #9,  »Last edited
Lets just talk a little about self resonance and Q factor. The more efficient a coil is at forming tank circuits then the longer those tank circuits will last. The resistance of the wires plays a huge roll in this and ultimately super conductors that offer zero resistance will help and technically speaking if there is no resistance in the wire at all and the Q factor of the coil was high enough and the efficiency of the capacitor is high enough then the tank could swing forever. We all know this is impossible and Stan always talks about the efficiency of components as being the only reason we cannot reach infinite voltage. The capacitor components and coil components would all need to be super conductors besides the connecting wires and it would have to be performed in a vacuum. That's not going to happen. If you want an efficient system that can resonate efficiently enough to perform the work that Stan is talking about then you need an high quality factor otherwise the voltages won't get high enough and quick enough. This means the choke wire has to be top quality and it has to have low minimum damping. BUT here is the most important bit, the wire which connects the chokes to the fuel cell - the higher the resistance then the higher the damping within the choke. What does this tell you? It tells you that resistance between the choke and water fuel cell (in de ionized water) is the absolute enemy. Even though the fuel cell may present an high impedance to encourage a tank circuit, the connecting wires are presenting a lower impedance. Lower impedance causes current flow in a system where you are trying to form a tank circuit and throws the system out of resonance. Therefore the connecting wires need to be the same resistance and inductance as the coil material with no impedance spikes anywhere along the way so that the wires are part of the coil. When you wind your chokes let the choke wire extend to the cells but insulate against short circuits. DO NOT increase or decrease the gauge of your wire connecting choke to cell, it will cause standing waves because of an impedance mismatch, the standing waves will reflect the voltage back towards the chokes and burn them out by inducing current.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #10,  »Last edited
The water fuel cell is by definition half of an AM transmitter. By that I mean that there is a voltage maxima and capacitance but there is no current maxima and no inductance. A normal AM antenna has voltage maxima and voltage minima, current maxima and current minima, it has an inductance field and a capacitance field. The water fuel cell lacks current and induction therefore it cannot transmit the AM signal. The reason it has voltage is because the chokes cut off the current and induction but allow voltage and capacitance through the same resonant action as any AM transmitter. Every AM transmitter must match the transmission line (coax) impedance and the antenna impedance to the oscillator impedance. Stan's system has to match the oscillator frequency (chokes) to the line frequency (wires from chokes to cell) but not the antenna frequency (water fuel cell). I'll tell you why you don't need to match the water fuel cell. In a normal transmitter, the impedance of the oscillator, transmission line and antenna is usually 50 ohms (not high impedance). The antenna on a 11m 27mhz system is naturally about 1000 ohms on a shunt fed and 75 ohms on a dipole and a matching section is needed which will bring the impedance down to 50 ohms and match it. If you don't do that you get standing waves which will reflect the signal back at the oscillator. If Stan's system operates at 5khz on the modulation frequency which is the resonant frequency of the chokes then the incident wave would be miles in length, the incident wave for 27mhz is 35 feet, as you come down in frequency in the incident wave goes up exponentially and 5khz would present an incident wave of 93600 feet. It doesn't matter if you cut the cell tubes to half waves or quarter waves or 32nd waves you would never get them big enough to tune to resonance and impedance match to 5khz, totally impossible. There is only one way to do it and that is use the negative choke as a impedance match but at less than a quarter wave. That means that the total length of the tubes which are acting similar to a dipole array in series with the negative choke are just under a quarter wave of 93600 feet. A 32nd wave works out at 975 yards total for negative choke and cell in series as in impedance match through a dc ground system. a 64th wave works out at 487 yards for the cell and negative choke. In transmission systems, anything less that a quarter wave is purely capacitive and that's part of the reason the cell takes on voltage. That is why the length of the tubes is not important and why the negative choke is variable in some cases - it's an AM impedance match.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #11,  »Last edited
So, in simple terms if you create a positive choke that is self resonant at a modulation frequency of 5khz and the choke is 500 yards of 30 gauge wire, the demodulation would be 5khz and the cell plus the negative choke would be 500 yards long plus a means of fine tuning. Hope people understand now. Those are not true wire length figures BTW just examples.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #12,  »Last edited
Now for those of you who want ball park figures, the total electrical resistance of Stan's secondary, L1 and L2 is roughly 220ohms. Have you seen this figure before? What does that tell you about the carrier frequency?
The electrical resistance of L1 is 77 ohms
The electrical resistance of L2 is 70 ohms.
What does this tell you about Stan's tubes? Their electrical resistance including the transmission wire is roughly 7 ohms. What does that tell you about whether they are in series or parallel? If they are in parallel what is the reactance of the system as you switch more sets of tubes on, will it remove the need for L2 to be variable? Those would be the questions I'd be asking myself.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #13,  »
Look at the chart, the resistance figures for L1 go up in frequency but is only 100 oms at 100hz where its resistance is at 1khz is 3.1kohms and 10khz is 1200kohms, what figure is missing from the chart? It's self resonant frequency where the resistance goes off the chart which is 5khz. 10khz is double the resonant frequency. They failed to mark its resonant frequency in the chart, why?
The carrier frequency is close to mains electric which is 50/60hz and the modulations are close to 5khz. I'll tell you what is totally fake on the chart, the secondary, L1 and L2 are closely matched in impedance at 1khz at around 2.5kohm/3kohm yet when we switch to 10khz the secondary is at 190k yet L1 and L2 have jumped to 1200k each, this is totally impossible and the true figures for L1 and L2 are 205k and 170k respectively at 10khz because I've measured them. What did they try to hide? They tried to hide the fact that L1 and L2 are coming into resonance as you approach 5khz. At 5khz L1 and L2 are approaching 10,000kohm and it depletes back down as you approach 10khz again.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #14,  »
In other words the chokes will not pass current at 5khz.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #15,  »
Also the inductance figures on this chart are totally made up, the chart is pure fiction.

#### securesupplies

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #16,  »
Nice Nav,  Thousands of words there, Of coarse I ask for video or pic?

#### Lynx

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #17,  »
That's amazing Nav, many thanks for sharing :thumbsup:
Good to see you again :-)

#### nav

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #18,  »
Quote from securesupplies on September 29th, 06:19 PM
Nice Nav,  Thousands of words there, Of coarse I ask for video or pic?
I was messaged to explain the am signal, that's what I've done. I've explained how and why the chokes work, they will not work any other way than choking an high impedance modulation from a low impedance carrier, without a carrier signal everyone is wasting their time believe me.

#### Gunther Rattay

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #19,  »
Interesting information, thx Nav!

What difference does it make whether L1-4 are on common core or separate cores?
How about gap or no gap according to tuning/adjustment?

#### nav

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #20,  »Last edited
Quote from Gunther Rattay on September 30th, 12:35 PM
Interesting information, thx Nav!

What difference does it make whether L1-4 are on common core or separate cores?
How about gap or no gap according to tuning/adjustment?
I tried both with air gaps and without air gaps but my air gap principle was wrong, we all make mistakes along the way. You can use chokes on the same transformer or you can use chokes on there own transformer BUT take note of this:- The phase of a choke that is on a separate transformer is different to the phase of a choke that sits on a core with the secondary. Study mutual inductance of multi core transformers to understand this then study the phase of stand alone bifilar chokes and differential mode chokes.
Stan uses bifilar chokes on several of his designs. The bifilar choke will only choke current at its resonant frequency where the Q factor is at it's highest and it will only choke parasitic frequencies that sit on carrier frequencies where the load (resistance) presents an high impedance at the parasitic frequency.
Consider the below low pass filter (picture). Consider what takes place on this circuit. The resistance is at low frequency which is the standard operating frequency (our carrier) and the filter will remove higher frequencies which are unwanted frequencies (our modulation). How does the circuit work and stop the unwanted signal entering the resister? When the choke L1 is resonant at the unwanted frequency it forms a tank circuit with the capacitor and the swing of the tank circuit uses up the unwanted signal via resistive losses between the two components. Sometimes, if the unwanted signal is too powerful for the capacitor there is a shunt to ground from one side of the capacitor.
Build a straight forward circuit consisting of a step up transformer rated at 50/60hz, any normal transformer of 1:20. Connect it to any resister that has a pretty high wattage or light bulb that is rated at 500v and 20 watt. Picture A describes this. Use a variac and transistor rated at 50w and drive the transistor at 50 or 60hz but any type of pulse provider. That is all you need to do in the first part. Get the light bulb shining as bright as it should be or measure the current across the resister. Then introduce a parasite into the AC sign wave, a modulation of 5hz will do but keep the modulation amplitude low at first, watch the amp meter on your resister and increase the modulation amplitude, the light bulb will become dimmer and dimmer as the amplitude of the modulation increases. This is because your 50/60hz transformer cannot work properly at 5khz, it's becomes inefficient at what its supposed to do, the flux in the core becomes too saturated and the bulb dims then the transformer will become hot. don't do this for too long because you'll burn it out. Increase the modulations so that the light bulb is bright or scope the resister so you can see those modulations across it while maintaining current flow. Now we have a system working with a paracitic signal which we are going to capture elsewhere.
Next step, get used to filtering before you take too big a plunge. Build circuit B. Make L1 resonant at 5Khz exactly and you all know how to do that. C1 is a 5kz crossover cap from any crossover circuit rated for 5khz. D1 is rated higher than current at R1 and L1 is 29 gauge on ferrite core. Before you can run you must first learn how to walk.
Start the variac at low voltage and light the bulb normally with no modulations at first, increase the voltage until its bright and maximum current is passing then start the 5khz modulations on low amplitude. Increase the amplitude gradually and you will notice the bulb is not affected like before. This is because the bulb presented an high impedance to the modulations and they were trapped in the transformer core. L1 and C1 now present a secondary path for the modulation which is shunted to variac ground as an half rectified signal. You cannot shunt elsewhere. If you turn the modulation amplitude up really high, the filter will work only to a certain point before the AC signal is totally ruined. When the system is running properly, place a scope across the resister and the modulations will be gone. This is low pass filtering the easy way.
Now we are going to collect the modulations in an easy way.
Circuit C consists of this :- L1 5khz self resonace, roughly about 80 Ohms resistance, L2 is 80oms same as L1 but is variable. D1 and D2 are same spec as Stan's schematics. The cell is two stainless steel plates 4 inches square 2mm thick and the wires connecting the cell to the chokes are made from extending choke wire. Wrap your chokes slightly too long then unwind enough from them to reach the cell. ONLY use de-ionized water so no current from the carrier can go through the water.
Do's and do not's:- Do not turn on the 50/60hz carrier frequency with the variac at 12v and draw full current into R1. Start at low low voltage and monitor on an amp meter so that the current does not exceed 500mA. Turn it on at 1v and raise the voltage steadily until you reach 400mA. Turn on the modulations at about a quarter of the voltage amplitude the carrier wave has . The light bulb will dim slightly, Use the variable setting on L2 until the light bulb dims more. Once it dims or the resistor shows less current across it turn the voltage up on the variac slightly and move the variable L2 till it dims again. Keep doing this in small steps until you reach 6 volts. Gas bubbles will appear on the plates and slowly start to rise. Keep doing it until you reach 12 volts and gas is flowing. At this point do not raise the voltage amplitude of the modulation or you'll blow the system, you can only do that with a full set of tubes.
What is happening?
The steel plates and L1 are totally impossible to impedance match. The capacitor is so far out of range of the 5kz L1 that you cannot get a tank circuit to form and filter the voltage just like the low pass filter did. L2 is actually an impedance matching circuit which tunes the plates to L1 impedance, without L2 it cannot work.
Why is the light bulb dimming when it was actually bright in the low pass filter? In the low pass filter system, the primary circuit dominates the inductance field in the choke and it's winding because the capacitor and L1 are shunting the load to Variac ground.
When massive capacitor plates are introduced the modulated frequency causes the system to get voltage hungry and that hunger is so high that it takes the voltage potential from the carrier inductance in the wire itself inside L1. The light is dimming because although there is current available to R1 the voltage potential is removed at an higher frequency than it can handle and voltage at R1 is negligible
. There is no current at the capacitor because it presents too high an impedance for current to flow which is the basic principle of choke systems.
Now here is the good bit. You can actually remove the resister (or light bulb) at R1 and remove D2 if you've learned to walk before you can run. You make the water conductive enough so that current passes through it with just the carrier wave. When you introduce the modulations the same rules apply but there is no way of tuning the circuit visibly. So what you do is place a bulb in parallel with your tube sets.
Always learn to walk before running, understand all the basic principles of chokes and why they work and where the energy goes. Learn how to harness parasitic unwanted energy instead of shunting it to ground and you WILL succeed.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #21,  »
Missed the ground from the primary in picture A, sorry
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #22,  »
Resister is 220 to 250 ohms by the way, at 50hz presents low impedance, at 5khz it presents impedance in mega ohms. Fuel cell presents impedance at 5khz in mega ohms, in series with L2 the fuel cell presents an impedance match. When impedance match occurs, L2 is happy to communicate with the fuel cell. No impedance match - no communication. Dc bias builds up on cell because of diode won't allow the pendulum to swing in tank circuit. Hope everyone is beginning to understand.
##### Re: The AM signal and how it works. Carrier and modulation
« Reply #23,  »
Also important. If you move to the nine tube set then the impedance of the system will change. The impedance of the tubes will change as you move up in size and the series impedance of tubes and L2 will change. Therefore, when calculating the size of L2 it is important that you do not go outside the range of the variable capacity when in series with the tubes. On 4 inch plates you can get away with it, on tubes that present a parallel equation connected to a series equation the math becomes extremely complicated especially in the light their total length may be 250 inches long in parallel sets connected to a series tuning coil. If you go bifilar it gets even worse because L2 cannot be variable so stay away from those till you understand it more. Once you establish some figures you can eventually do away with variable L2 but if you are down sizing to an injector size fuel cell, variable L2 will need to be reconnected until you find the resonant/none resonant inductance and capacitance of the system at both carrier and modulated frequencies.

#### Gunther Rattay

##### Re: The AM signal and how it works. Carrier and modulation
« Reply #24,  »Last edited
so true!

... thinking about practicability of LTSpice simulation of your circuits above first ...