32-ohm earphone speaker as a dynamic microphone
"Michael Black" wrote in message
xample.org...
I get the feeling these were the solid state equivalent of the one tube
transcievers used to homestead the higher bands. They were a modulated
oscillator on transmit, a superregenerative receiver on receive, and a
common audio amplifier. There the space and cost of a tube meant they
switch it between the two functions, but since it was a modulated
oscillator, it was a simpler arrangement than switching between a
superregen and a crystal controlled transmitter.
Nowadays when transistors are almost ten-a-penny, it is the switching
that is expensive, so otherwise than as a novelty, there's not much
to be said for single transistor rigs.
I have in my museum pieces a boxed PM2A valve and the conditions
of sale printed on the bottom say that it must not be sold to the public
for less than 8 shillings and 9 pence, which pre-war was about 10%
of the weekly take-home pay, but imagine paying £$40 today for
each active device !
|