Ingenuity: not just by Hams

source: https://youtu.be/ihkRwArnc1k  

At about 16 minutes into this video two Japanese semiconductor researchers explain how they solved the problem of maintaining the temperature of Germanium to within 1/10 of a degree C.  Their meter only had graduations of 1 degree C.  So they attached a mirror to the meter needle and used reflected light to increase the resolution of the meter by projecting the reflection on the wall.  This magnified the scale so the temperature could be read precisely.  Ingenious !

the mirror on the meter needle

the reflected light on the wall

The video as a whole is quite interesting, the grown transistor development at Sony is pretty neat.  Also the video mentioned that the transistors in the Regency TR-1 were grown silicon transistors.  Some web sites dispute this.  I had an early Regency transistor but couldn't fix it and ended up removing all the parts.  I'll have to see if I can find the transistors.

Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm