*Use a fork to scoop water out of a glass to satisfy your thirst.
I will work, just not well.
* * * * * * * * MikeK


True, but operating crystal radios is much like sailing.

Maybe multiple taps is not that bad an idea.

- I never saw a crystal radio optimized for such a small tuning ration
that the LC had a fixed impedance. A 1-to-3 tuning ratio is quite
normal, and tank impedance will therefore vary considerably.

- On medium wave the impedance of the electrically very short wire
antenna will vary, but not that much. It will stay probably in the
order of a kiloohm or more. On shortwave it will swing considerably.

- If the receiver has to resolve different stations or at least
clearly separate different SW broadcast bands (to listen to the most
powerful broadcaster in each band, more is not doable), it may make
sense to reduce the loading below optimum energy transfer at the
resonant frequency.

This suggests that a coil with multiple taps could be useful. If the
radio has a tapped coil and 3 croc clips (one each for the tuning cap,
antenna, and detector) the user has to optimize over 3 dimensions in,
and 2 dimensions out - wanted signal level and interference.

Great fun, but not easy.

The human ear is not linear and tends to be a bad level measuring
instrument. It helps if the radio also has a microamp-meter to make
relative linear comparisons in total signal level. A 50uA meter may
have a DC resistance of 2kohm and load about the same as a magnetic
headset, but a 500uA may be sensitive enough and load less.

The combination of separate improvements that the ear alone could not
judge may in the end be considerable.

A digital voltmeter would be so high impedance as to be practically
invisible even at very high impedances too, but it has a battery
powered DC amplifier. IMO it is aesthetically incongruent with a RF-
powered radio.