It all depends on the equipment you are using. The typical off-the-shelf SSB transceiver requires 20 amps at 12 volts when operating at full power (i.e. in the neighborhood of 120 watts pep). The Handbook copper wire table rates 14 AWG wire at 32 amps in open air and 17 amps when bundled or in conduit. This would seem to imply an upgrade to 12 AWG. But that ignores the fact that your transceiver isn’t drawing anywhere near a constant 20 amperes, whether you are operating SSB or CW. The limiting factor is not the current per se but the heat the current produces. Taking account of this, 14 AWG should be perfectly OK in this application.
I’m a little more “iffy” about using wire as thin as 24 AWG for the control circuits without knowing the current being drawn, that’s especially true for whatever wire is being used to activate the power supply when the rig is turned “ON.” With a modern, solid state power supply it probably doesn’t have to carry the full ac current being drawn from the outlet to the power supply, but it would be well to measure the actual current.
In conclusion, your best guide would be the manufacturer’s instructions.  

Miles B. Anderson, K2CBY
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