Active Sun impacts of HF communications
The 11 year solar cycle has brought a day of reckoning for CB radio. The short winter days will give some respite, but skip is sometimes heard when the sun is below the horizon. A sure sign of increased ionization supporting increased MUF up into the 27 MHz CB radio range.
Shortwave listening in the 5-10 MHz range impacts are not as dramatic for high power shortwave stations vis-à-vis SNR. With broad frequency choices, ham radio takes advantage of a clearer diversity of frequencies. If more people used SSB on CB, frequency sharing would be much more efficient. Without the capture effect of FM, the typical AM mode leads to loud squealing heterodynes. Narrowband FM on 27 MHz CB radio apture effect wouldn’t be nearly as effective.
GMRS doesn’t have quite the appeal of 27 MHz CB since the user base on 462 MHz is split between incumbent businesses who are in no mood to chat (and may even be paying for a repeater), inexpensive FRS walkie talkies, lack of enthusiasts. eBay sells radios from a distant city trading up from crystal controlled radios. Even the crystal radios are often two or four channel. We could setup a common calling frequency for chit-chat and then have a second channel for each group.