Radio manuals usually describe the external antenna jack as dedicated to bands above medium wave. Using an external MW antenna is typically accomplished by some sort of magnetic coupling.
I think the first radio that I knew allowed the external jack to be used for MW was my Panasonic RF-085 with wire posts for the antenna. That was 40 years ago. The second was the Tecsun PL-330 that has this ability through an undocumented process: press and hold the numeric button 3 to switch between external and external antennas. The Tecsun PL-990 has an explicit Internal/External switch on the front panel. I found greatly improved results with a long wire and ground, especially on longwave.
I once owned a Grundig G5 radio where the external antenna jack automatically switched to external when plugged in. I only recently learned this from a post from Jay Allen. I just discovered by experimentation it also works that way on the Eton Elite Executive, a successor to the G5.
The tiny Raddy RF760 works the same way, automatically switching LW/MW from internal to external antenna when one is plugged. This is documented, but with a peculiar disclaimer:
External antenna of this machine temporarily supports external input mode. Insert the external antenna or in MW band mode, the frequency ranges from 54KHz to 1710KHz (the manufacturer does not guarantee the performance of this function. It is only used to provide users with the pleasure for radio reception).
The bottom of the new combined LW/MW band is 150 kHz, not 54 and it works quite well.
The best results came from the Qodosen DX-286 that provides clear documentation on switching between internal and external antenna on LW/MW. Reception is phenomenal.
As I get out other radios, I’ll give the external antenna jacks a test, and perhaps expand this list.
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