Reactance

[Beetle]

So the net reactance in real life on channel 40 is +0.105 (very slightly inductive). You're wondering how to cancel this.

First question I'd ask is, how much capacitance is in the circuit already? It isn't zero; that'd be impossible except on paper. It has to be enough capacitance to produce a reactance on Ch. 40 that balances, or nearly balances, the amount of inductive reactance in the circuit at the same frequency. Don't think of adding a lumped capacitance value to the mix -- just work the DIFFERENTIAL between what's already in the circuit and what it needs to be to resonate with the inductance.

 

[freecell]

matching a low Z source to low Z load........

 

[C2]

Hmmm, would that work here? With the measurements I can make, I should not need variable devices and should be able to calculate the value of the fixed devices. Of course...those are series devices.

I knew how a tuner worked, I was just interested in the theoretical discussion, kind of like what happens to the mass of an object as it approaches the speed of light, but this seemed a bit more tangeable.

 

[freecell]

"would that work here?"

yes.