The "typical" (many times a day) frequencies for simultaneous EAMs are 4724, 6739, 8992, 11175, 13200, and 15016 kHz, all 6 carrying the same audio. These are not the only frequencies that might carry parallel EAM transmissions, they are just the most common. How clearly you hear each frequency will depend on propagation. How many echos you hear in a transmission, and how deep they are, will also depend on propagation.
When the source is airborne the maximum number of frequencies can be smaller, depending on the platform. Some aircraft types only support 3 or 4 parallel networks / transmissions on HF. When the source is airborne you might also find the same EAM on UHF.
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