View Single Post
  #1   Report Post  
Old April 14th 21, 07:53 AM posted to rec.radio.amateur.dx,rec.radio.info
DXZone via rec.radio.info Admin DXZone via rec.radio.info Admin is offline
external usenet poster
 
First recorded activity by RadioBanter: Mar 2020
Posts: 422
Default [DXZone] Sunspot Index Since 1750


The DXZone.com Amateur Radio Internet Guide

///////////////////////////////////////////
Sunspot Index Since 1750

Posted:
https://www.dxzone.com/dx34352/sunsp...ince-1750.html

Propagation/Sunspots
The yearly, black, up to 1750, and monthly red, from 1750 up to now,
sunspot numbers provided by the Royal Observatory of Belgium SILSO