Yes, in the USA, shortwave low power stations may operate in the 22 meter shortwave band from 13.553 MHz to 13.567 MHz, with a field strength limit of 10,000 uV (microvolts) per meter at 30 meters from the antenna.
About 1.8 mW to 3 mW would be needed, depending on the antenna. Unlike low power AM medium wave, however, there is no limitation on the size or type of antenna, feedline or ground for shortwave low power stations.
It would be an almost unknown operation here in the US, as very few people own shortwave radio tuners and even fewer ever listen. In other parts of the world that might be different.
Ready made shortwave transmitters and shortwave transmitter kits can often be found on Ebay Shortwave Transmitter listings - as always on Ebay, read descriptions carefully, ask questions and buyer beware.
Want to check out the shortwave bands? Try one of these affordable receivers by visiting these Amazon.com Shortwave Radio listings or Ebay Shortwave Radio listings.
Here are some schematics, plans, illustrations and ordering information for low power shortwave transmitters:
Amplified modulation section design
Hartley Oscillator Kit info
Talking Pixie modified ham transmitter, and filter
13.560 MHz ISM Band Shortwave Home Radio Station on ebay -
Robust, handcrafted low power 100mW shortwave radio transmitter operates on 9 Volts DC.
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