--- In ultralightdx@..., "jim_kr1s" quotes me:
> "First, the AM front-end of the Si4734 is a tuned-tank circuit with a
> fairly conventional LNA and quadrature mixer as shown in the block
> "As Roy has pointed out, the loopstick (or air-loop) inductance is
> resonated with an on-chip varactor, which tunes in small discrete steps.
> This tuning is done each time the frequency is changed."
Radio reception and antennas involve complex, multidimensional tradeoffs,
so I'm not taking sides (yet, anyway) in this debate. I do agree with
Jim that a necessary first step to resolving the disagreement is to
carefully understand loopstick resonance and how the Silabs' tuning
method differs from that implemented in all other radios.
For the techies in the group who are interested, I think this can
answer most of your questions: US Patent 7561865 .