Matt W1CDN14h ago
How do ionosondes/chirpsounders transmit across lots of frequencies with only one antenna? #hamRadio
Show threadBrendan Francis O'Connor14h ago
@W1CDN Hey @xssfox, any assistance for this ham fren?
Show thread1.3.6.1.4.1.6151313h ago

@Ussjoin @W1CDN Maybe @vk5qi

I assume its just a wide bandwidth antenna and probably a transmitter design that doesn't care so much about swr?

Show threadMark Jessop (VK5QI)
@xssfox @Ussjoin @W1CDN Ionosondes are typically using very broadband antennas. For verticals, things like biconical monopoles ( https://www.lencom.com.au/products/antennas-base-station/hf-broadband-monopole ) and for vertical incidence, terminated delta antennas ( https://www.lencom.com.au/products/antennas-base-station/delta-antennas ).
HF Broadband Monopole

The Lencom Broadband Monopole (biconical) antenna is perhaps the most efficient, omni-directional, broadband antenna in existence.

Lencom
12:44amWeb