The immediate followup question is whether or not they were given any additional equipment, to include something as "small" as an additional radio frequency to use.
It was not a "small" thing to add an additional frequency to AE's radio:
From
"Radio equipment on NR16020." See that link to pick up the footnotes.
Design"The Western Electric Model 13C radio transmitter was a fifty-watt output, crystal-controlled unit. The original design of this transmitter produced amplitude-modulated (A-M) voice (A3 emission) signals only. The transmitter aboard NR16020 was factory-modified to incorporate Morse code (C-W) transmission capability (A1 emission) as well.
"Model 13C was the factory designation for a three-frequency transmitter operating in the 2500-6500 KHz range. A 1939 source (Morgan) illustrates a Model 13CB, a three-frequency radio with C-W and low-frequency (325-500 KHz) capability. Earhart’s Model 13C was factory-modified to include 500 KHz operation, and was probably the prototype for this later off-the-shelf version."[3]
"AE’s rig worked from 12 volt DC power."[4]
Selecting transmission bands"The 13C was originally designed to operate in the high-frequency (H-F) range of 2000-6500 kilohertz (KHz), on three independent channels. Each channel employed its own frequency-control crystal, and tuned circuitry in all three radio-frequency stages.
"Channel shifting was accomplished by means of a multi-gang switch to select crystals and tuned circuits for each channel. The switch was activated from a crank on a remote control head located in the cockpit, linked to the transmitter through a flexible tach-shaft resembling an automotive speedometer cable.
"All tuning adjustments were inside the transmitter cabinet and were set by a technician prior to flight. No operator-adjustable tuning controls were employed."[5]