A national calling frequency in the USA is a radio frequency that is widely accepted and understood to be a place to start communicating with other hams.
This frequency is established for each RF band under the voluntary US band plan and is not regulated by the FCC. It is routinely monitored by any number of radio amateurs and is likely to result in a response when calling CQ or Mayday or SOS.
The US band plan shows calling frequencies for various modes (CW, SSB, FM, AM, digital) in different bands. A calling frequency list includes not only the modes but adds specific activities (expeditions, power levels) as commonly practiced.
For new hams who are likely to get started in local VHF/UHF operation, the national calling frequencies to be concerned with are 2m and 70cm FM simplex (non-repeater). These are 146.520MHz and 446.000MHz, respectively, and should be included in your radio’s scanned channels. If you regularly use 1.25m, 33cm and/or 23cm bands, there are national simplex calling frequencies defined per the band plan for you to look up.
Be aware that the national calling frequency for whatever mode and activity is only a place to start communicating. Protocol and common courtesy require that once contact is established, you move to another frequency (QSY) to leave the calling frequency open for others to use.
The national simplex calling frequency is sort of a universal (within the USA) place to make contact when you are not sure where to start. It is particularly useful when traveling to a new area where you don’t know the repeater frequencies, offsets and access tones. It’s also a great place to get assistance in an urgent situation.
Note that Canada largely follows the US national calling frequencies so our friends north of the border can be included in this scheme. Other countries may or may not have national call frequencies, or may unofficially follow the US plan.
This may also be a good time to remind all hams that while even the Technician license grants full privileges on VHF/UHF bands, and your 2m FM transceiver tunes from 144-148MHz, doesn’t mean you can just randomly pick a frequency and key the mic.
For one, chances are nobody will respond because it’s unlikely anybody is monitoring your random frequency. But mainly it’s because there is a clearly defined band plan for 2m and it’s not all FM simplex and repeater allocations. Take a look at it:
You can see that only a portion of the band is allocated for FM simplex or duplex (repeater) work. There are clearly-defined chunks for CW, SSB, beacons and satellite operation. You need to stay away from those frequencies unless you’re operating those modes and activities per the plan.
NewHams.info 
Thanks, Jim. A good reminder!
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hi im ken o liten to all the ham novic techician ch and others channels band a/ band b/ band c / band d all from 26.065 to band d freq 28.765 to29.695 segment2 display2 . i have cb / ham freq
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I never hear any traffic on 145.62 or 446.00 I’m assuming that since these are simplex contacts there are no PL Tones, but do offsets apply?
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Gary, the nature of simplex means no offsets, so 146.52 or 446.00 is both transmit and receive frequency. Only repeaters use (truly need) frequency separation (offset). As you already indicate, there is no CTSS/PL or other selective calling with simplex. Jim
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Interesting AF5NP so you are saying there is no CTSS/PL ever used for simplex. That doesn’t seem to jell does it, or perhaps in the East they’d say, ‘that dog probably doesn’t hunt’.
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mobilesecured, you are correct in that some hams use tone squelch (PL) on simplex frequencies for a few possible reasons. My reply to Gary was in the context of the post topic of a national calling frequency specifically. It would be especially useless to have PL activated on a national call simplex frequency because that would defeat the purpose of having an open, accessible spot that everybody knows and can use without worrying about tones or codes used by PL/ tone squelch. I am aware that there is (or was) a movement to apply tone squelch to the national call spots, but unless or until that becomes commonly adopted, the average ham will not know how to access or use national calling frequencies.
Thanks for pointing out that my blanket statement does not apply universally, just as intended for national call.
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try 146.520. easy to transpos the numbers.
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Once you make initial contact on 146.520, what frequencies may the two hams switch to? Assuming the new ham initiates a contact, it’s likely they don’t know what repeaters are close and may not yet be able to quickly enter frequency, offset, and tone?
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Gerry, tough question; I have not seen any guidance here. Easier on HF where you could simply say up 5 or something like that. I suppose you could do same with VHF/UHF simplex. More likely a local ham will respond and know the area repeaters to suggest, but like you said, that may involve setting up access codes and offset, etc., which can be awkward while diving. Wish I had a better answer… Jim
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I think, with some use this guy will figure it out. Where there is a will, there is a way.
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USE : The repeater guide is available online,
or go to ARRL site:https://www.arrl.org/clubs
Contact the appropriate club ahead of activity.,
listen on the local repeater that is active and open,
then request your needed frequency info.
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I monitor 146.520 because we live less than a mile from a major interstate. The frequency is never that busy, but when calls do come we generally stay on that frequency for short responses of 10-15 minutes.
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Jim, here in Georgia 2M is pretty crowded and there are designated/allocated simplex frequencies. (And even some of those have area restrictions on them.) What I am doing is printing the list of frequencies with the unrestricted ones highlighted for a QSY from https://sera.org/ KQ4GEL
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Thanks for sharing, Mark! This may be helpful to others, especially in your area.
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