Barry wrote:
> I beg to differ.
> I used the term "all things being equal".
> Hence issues of shielding integrity, supply regulation and tuning apply in
> the hypothetical case of the amplifier being pushed close to its limits
> and a larger one working on the linear part of its transfer curve.
OK, I stand corrected!
All things equal, the higher power amplifier will have more TVI and
more IMD.
> distortion products. Also in the real world the budget amps tend to be
> poorly shielded and lack features such as vacuum variables which typically
> show lower impedance to vhf than breadslicers do, hence the tanks work
........and you know that because?
Factually, air variables can and do offer very low impedances to
VHF. As a matter of fact, the impedance is often comparable at
VHF. Vacuum caps have lower ESR, but in this application that
isn't important.
It's more important how parts are laid out than how expensive they
are.
> considerations apply to audio amplifiers: the overbuilt ones look better
> when the output is analysed and sound better to the ear. Also issues of
That's because audio amps, unlike RF amps, freely pass harmonic
distortion on to the load. That's why a single-ended class AB amp
is just as clean as push-pull in RF, but a single-ended amp is
dirtier at audio.
73, Tom W8JI
w8ji@contesting.com
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