2182...monitored or not?

Making a vessel specific emergency radio placard, I see the CG puts out generic templates to fill in and post. Of the templates you find by searching “emergency radio placard uscg,” you can find a couple. The ones I could find, even the ones put out by the USCG, have mf 2182 listed as their designated frequency. Only problem is that in 2013 they supposedly stopped monitoring 2182.

I read multiple articles about the USCG complaining that they keep getting calls on 2182 even though they stopped monitoring it.

Has anyone called the CG and asked, or let them know their templates provide misinformation?

Who don’t you? Even if others have already the more calls they get the more likely they will be too change it.

How do they know they are getting calls on that frequency if they don’t monitor it? Make sure to contact several CG offices for an anwer so you end up with several options to choose from.


To be specific this is what I am talking about.

I was doing an SSB install and could not get the USCG to answer a test call on 2182 until I called them on 16 and they turned up the volume. Even when they did “monitor” it, I think it was so noisy they either turned it down or turned the squelch way up.
Here are the frequencies they do monitor:
I would think that the Big Red Button is a far better option now.

Didn’t this have something to do with a push to use 121.5 to improve comms between ships and aircraft for SARs?

No, not at all. 2.182 MHz has been a distress frequency for almost 100 years. From say the 30s to the 70s it was AM and many boats only had 2-3 MHz AM radios. Practical range from a small boat on 2182 could easily be less than VHF during the day and could be about 100 yards if there were a lot of thunderstorms around.
So now in 2019 we have both HF and VHF DSC that require no humans to constantly listen to chatter and noise plus EPIRBs/ELTs/PLBs and boats that do have 2 MHz capability now have it because they have a SSB set that covers all the way from 2 to 25 or 30 MHz.
Given all that, the CG decided to quit maintaining a voice watch on 2182, they figure distress calls will come in on DSC, EPIRB, or 4/6/8/12/16 MHz SSB voice channels.
121.5 MHz AM has been the aviation distress frequency since WW II. You certainly can talk to airplanes on that frequency if any are around and monitoring it. Any aircraft doing SAR work would normally have a marine VHF, they wouldn;t count on you having an airplane radio. I do have one, but that is probably not all that common??

Maybe they do now. I don’t have time to look it up right now but I remember a few FUBAR situations developing during SARs because choppers and ships couldn’t communnicate and it created an impetus to do something about it.

2182 has not been monitored for years.

4125 is the primary calling and distress channel

I am sure that has happened, but the 2182 change was totally unrelated to that. What really was the end of it for the CG was the grounds and antennas for 2182 on shore were deteriorating and no one wanted to spend the cash to fix them since DSC got invented.
For airplanes and ships, it is a Venn diagram issue. The basic radio any aircraft would have is an AM radio that works from 118-136 MHz. Military aircraft will add 225-400 MHz AM.
The basic radio any boat/ship has is a VHF-FM radio that works from 156-162 MHz FM. There is no overlap there at all.
If you have a bunch of aircraft and boats/ships trying to work together, normally you want all the surface vessels to have aircraft radios or all the aircraft to have marine radios or there is no overlap and no comms. I do carry an aircraft HT with me, but I have it anyway from flying jobs. I can’t say a lot of others do this.
Some aircraft have HF/SSB radios and these work the same as the HF/SSB radios on a ship. You can communicate that way if you have a common channel decided on in advance, but that would not be done for short range comms if there was an easier way. For random contacts it would be next to impossible. Normal airplane SSBs don’t have any DSC, so you can’t ring the ship. Normal ships don’t have the flying version of DSC, AKA SELCAL, so even if you knew what frequency to call the plane on, if they have SELCAL turned on they won’t hear you.

Of the airborne SAR assets I am familiar with (CAP and USCG/Aux), both have Marine VHF-FM available. I’ve also heard SO and municipal helos on Marine VHF. The only service I can’t vouch for is non-USCG medivac.
121.5 isn’t a SAR channel anyway - 123.1 is the proper channel for SAR ops. (ITU standard worldwide).

It’s been awhile since I was active. You’re correct. 121.5 is not a SAR channel but a guard frequency designated for aircraft declaring an emergency.

2Mhz frequencies will far out distance any VHF signal. Being Audio Modulated it does make a lot of noise and a great number of people would certainly turn the volume down. The squelch option is not a good way to utilize AM should your radio actually engage this while in AM mode. Even a moderately effective Antenna in this band will necessitate quite a bit of room and powerful shore side stations often require several acres, not to mention the upkeep duties.
Army and Airforce MARS stations utilize these frequencies as do innumerable Hams it all kinds of modes as these bands are the only radio waves good for continent to continent communications in the event of satellite and land line failure. Of course there are moon bounce and other things but digital modes on 2 or 3 Mhz will always get through.

I’d think that some clever software could result in a squelch that triggered on speech rather than carrier strength. It could have a variable threshold based on confidence level.

Icom marine SSBs use voice squelch AFAIK. It is better than the basic squelch that is just on ANY sound, but you still lose weak signals.


The relatively poor installations on many boats coupled with a ton of static from thunderstorms could make low powered comms using AM on 2 MHz unworkable past the range we get with VHF now. A ship with AC power or 24 volts and room for a big antenna and that steel hull for a ground plane of course did better, but you still have very high ionospheric absorption during the day.
I operate on 160 meters from my boat just under 2 Mhz and while I get out at least for a few hundred miles at night, I can’t get anyone past maybe 50 miles when the sun is up.

The 4 MHz and up frequencies the CG monitors now have better range :wink:

The military on land uses low mounted horizontal antenna for NVIS to stretch out a little farther.
We just put up an inverted L at my camp house for the 160 contest this weekend. Works well with the saltwater ground.

2182 kHz is analogous to channel 16 on the VHF band, but unlike VHF that is limited to areas of about 20 to 50 nautical miles depending on antenna height, 2182 kHz environment frequencies provide a reliable range of about 50 to 150 nautical miles during the day and 150 to 300 nautical miles or sometimes more at night. For a good range a sound earth connection and especially a well dimensioned antenna makes all the difference. On smaller ships and yachts that often leaves to be desired, that is the antenna length. For a quarter wave length antenna 34 m of antenna wire is needed. The reception range of even a well-equipped station can be severely limited by static caused by thunderstorms/lightning. Ever been on Lake Maracaibo?

We could almost always communicate on 2824 kHz when sailing in the Mediterranean near Italy with the Dutch coastal radio station Scheveningenradio over a distance of more than 1.000 miles. This was probably caused by some tunnel effect which also enabled us to listen to Dutch medium wave radio stations when rounding Cape Good Hope.


Wood or glass powerboats was not going to get anything like the ranges you quoted, the antenna would be maybe 23 feet (7 meters or so) or less and the ground marginal. ERP was likely around 20 watts out of a 100 watt radio.
Sailboats were somewhat better off, at least they could use the whole backstay. Back before we all got the big $$$ navtec insulators for SSB installations, sailboats all seemed to have telephone pole guy wire insulators in the backstay. They were OK until stressed to the point they shattered, at which point if the interlocked loops held you instantly got 6" slack.

Generally the porcelain insulators were not strong enough to withstand the forces in the backstay. We used to make them from Delrin rod in which we drilled two holes. We also milled material from the holes with a depth of half the backstay wire to the end of the rod so that it had a snug fit. See the rather primitive drawing to give an idea.


Polyoxymethylene (POM), also known as polyacetal, is a polymer that mainly has an industrial application because of its hardness. The substance is also known as the Delrin monopoly, developed by DuPont. Delrin is often used for parts in machines as a replacement for metal. The advantage is that it does not oxidize and that no oil or ball bearings are required for smooth mechanical mobility.

On medium wave frequencies propagation occurs mainly with the help of the ground wave. For a good range a solid earth connection is then essential. On wood and glass boats this is a problem. A not so ideal solution, but better then nothing, is to install a Dynaplate on the hull. It is a porous bronze construction which must be kept clean and certainly not painted!


Length: 152mm
Width: 51mm
Height: 13mm
Distance between holes: 63,5mm
Weight: 1.4KG

On larger yachts I have also seen larger, 1x1 foot, gold plated earth plates with a wrinkly surface. The idea is that the uneven surface has a larger earthing area.