Nice eQSL card from PA6GST received today:
Wednesday, 19 May 2021
Friday, 14 May 2021
QSO with 9A and GI on 70 MHz
This afternoon some sporadic E clouds were present:
In the evening strong signals from Ireland and Northern Ireland appeared:
QSO's with GI4SJQ, GI4SNA and EI2FG were made.
Wednesday, 5 May 2021
Schottky diodes
A Schottky diode, also known as Schottky barrier diode or hot-carrier diode, is a semiconductor diode formed by the junction of a semiconductor with a metal.
Typical metals used are molybdenum, platinum, chromium or tungsten, and certain silicides (e.g., palladium silicide and platinum silicide), whereas the semiconductor would typically be n-type silicon.
Schottky barrier diodes have a low forward voltage drop and a very fast switching action (typ. 5 ns).
A silicon p–n diode has a typical forward voltage of 600–700 mV, while the Schottky's forward voltage is 150–450 mV. This lower forward voltage requirement allows higher switching speeds and better system efficiency.
Lately I purchased a bunch of BAT85 Schottky barrier diodes. A typical value for its forward voltage is 200 mV.
I replaced four Ge diodes by BAT85 Schottky diodes in my field strength meter. http://pa2rf.blogspot.com/2020/07/fieldstrength-meter.html?m=1 .
The performance of the meter has certainly increased (higher sensitivity).
More info:
https://en.wikipedia.org/wiki/Schottky_diode
Bunch of BAT85 Schottky diodes