Any law enforcement agencies use hf channels?

[ManFish]

I monitor local law enforcement channels & they all appear to communicate above 30 MHz, does anyone know if there are any law enforcement agencies anywhere that transmit on hf channels? I've tried searching various websites without any luck & I have many friends who are local law enforcement officers, however they never heard of any communications systems transmitting on hf channels.

Manny

 

[E-Man]

If memory serves, Eureka CA, Humboldt County. There was discussion here about such a system, but my search results came up empty.

 

[ka3jjz]

There are some agencies that maintain a ham station for use in case of emergencies. We have such a station in Anne Arundel county Maryland, and I know other counties do as well. But nothing for normal, every day use.

73 Mike

 

[brandon]

Customs and Border Protection and the US Coast Guard come to mind.
Yesterday I logged one of the USCG aircraft on an LE mission "down south". Mostly encrypted but patience always pays off

 

[mm]

There was a district attorney office or some similar agency in Northern California that applied for and was granted some HF channels last year.

There reasoning was that due to the terrain they could not use typical public safety frequencies.

 

[E-Man]

There was a district attorney office or some similar agency in Northern California that applied for and was granted some HF channels last year.

There reasoning was that due to the terrain they could not use typical public safety frequencies.

Thats the info I was referring to, but could not find a link. It was an interesting article.

 

[ManFish]

Thanks gents, with your assistance I accessed a special federal communications frequency database & found the two operating channels that their investigators communicate on when they are in the field. I checked with a friend of mine that is a sergeant on one of the local law enforcement agencies where I live & he said it was legal to share that information as the district attorneys office obviously would employ special transmission safeguards to their communications system. They are 154.875 mhz for urban communications & 3201 khz for suburban & rural communications. The Ten-Tec RX-340 appears to be a pretty reliable receiver to monitor their hf channel.

Manny

 

[DaveNF2G]

It is lawful to share that information because it is in public records.

 

[longreach]

if you really wanted to go for a stretch NSW Police in Australia also use HF in the far west of the state. South Australia and Western Australia do as well.
cheers

 

[KMA367]

Thats the info I was referring to, but could not find a link. It was an interesting article.

Here it is, though the off-topic newspaper links are probably all dead: http://forums.radioreference.com/ca...forum/117202-humboldt-county-going-retro.html

I tune the freq in now and then, but haven't heard anything at all.

 

[ManFish]

Thank you Longreach for the information for hf downunder, would you happen to know what channels they use or what site I can access to obtain them? KMA367, that is quite a story about that DA fellow, I wouldn't mind being a law enforcement officer in California, but not in his jurisdiction, too many problems, thanks for the news link.

Manny

 

[longreach]

hi there try these frequences
3253.5khz, 4561.5khz, 5181.5khz(also shared with SAPOL and WAPOL), 6906.5khz, 7661.5khz (shared with SAPOL and WAPOL)
also SAPOLice use 10.296.5khz
info courtesy of VKHam.com - Australian Amateur Radio
In NSW's case it's not real busy only a handful of cars use it when they run out of VHF(78mhz) reception. the transmitters are located(for NSWPOL) at Dubbo NSW and is controlled from Tamworth, from what i understand the desk is not manned and only gets manned when the SELCALL gets triggered. in the other states cases the areas they have to cover quite simply just dont have the infrastructure there. im guessing you'll get more activity from SA and WA.
WAPOL also use 9054.5khz and 3825.5khz too.
i think there in LSB, been a while since ive listened.
hope this is of help, there is a bit more if you google 'hf police frequences australia'
cheers
Matt

 

[mancow]

Could any of this be reasonably heard from the US?

 

[longreach]

Wirelessly posted (Mozilla/5.0 (SymbianOS/9.2; U; Series60/3.1 NokiaN95-3/20.2.011 Profile/MIDP-2.0 Configuration/CLDC-1.1 ) AppleWebKit/413 (KHTML, like Gecko) Safari/413)

not sure its a long way over there. You can only try?

 

[ka3jjz]

Could any of this be reasonably heard from the US?

A little science is in order here to answer this question. For the most part, for the freq below 9 mhz, both the US and Australia will need to be in darkness to have a chance. The further east you go, the harder it's likely to be. Early morning in the east coast is a possibility, though a small one. The 9 and 10 mhz freq might be audible during daylight hours, but both the US and Australia would need to be in daylight for this to be possible.

Keep in mind that Australia is in their summer months; summer means more absorption of lower frequency HF, so even less signal than normal would be making it out. Adding to the difficulty is the type of antennas this service is likely using - verticals and low dipoles that would likely radiate in a pattern that would concentrate the signal in a range rather like an umbrella (yes, that's a huge oversimplification of NVIS) and probably using rather low power - 100 watts, certainly no more than 1kw - would add to the difficulty. It can be done - hams do it all the time using other kinds of antennas, but it's tough.

Bottom line, it's a tough catch to be sure, but with a good antenna and receiver, and awareness of the time differences between Australia and the US, it's possible. There are many utilities - some of which are linked in our wiki - that can help you determine daylight/darkness paths between 2 points. Some receiver control software packages even have such a utility built-in. As I type this, GeoClock shows the west coast of the US and Australia are in darkness, so if I were trying for this, I'd likely start with the 7 mhz freqs and work down.

73 Mike

[edit] Come to think of it, it's likely the base stations are running more than 1kw - I'm unfamiliar with Australian rules and regs. As a very rough comparison, when the ABC was still running regional HF stations, it was quite possible to hear them on 4, 6 and 9 mhz frequencies, even on the East Coast (during the right time of morning, of course). I very much doubt the base stations would be running more than these old ABC outlets did - 5 or 10kw. longreach?

 

[E-Man]

Just curious, have we been trolled?

 

[ka3jjz]

Quite possibly, but this Aussie information is very interesting. 73 Mike

 

[longreach]

hi all, yeah the AM(MW) Band stations run quite often more power than above. the commercials in the state capitals run about 5KW the ABC quite often run up to 50kw. quite often country stations will only run 1-2kw. as for short wave im not sure.
just looking at the ACMA page though all the transmitters are only licenced at 100 watts except all at middle head in sydney which are 400 watts.
cheers

 

[DaveNF2G]

This thread has gone completely off the rails. Lock, anyone?

 

[ka3jjz]

err...No. this thread has migrated to discussing Australian law enforcement use of HF (see longreach's response, message 12). The original poster did not specify US only.

73 Mike