CMED - Static (Encryption?)

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wpannone

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I'm in Greenwich and I can hear an ambulance sign on perfectly on Med 5. When they transport and patch in with Greenwich Hospital on Med 1, the first "Greenwich go ahead" transmission is heard but after that it is all static and I can't hear anything the ambulance is saying to the hospital. Why is this, encryption? Do I need certain PL tones?

Only once have I actually heard a full Greenwich Medic > Greenwich Hospital conversation while they're enroute. I was astounded! Why did I hear it that one time and never agin? Can someone help me fix this? I appreciate the help I get as always! :)
 

garys

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It's because the Med Channels are mostly not repeated. Med 10 and Med 9 usually are, but the others often aren't. Looking at this page Southwestern Regional Communications Center , it's likely that Med 5 is repeated. Med 1 is not repeated, it's a duplex channel. I'd guess that any of the channels listed as "EMS Dispatch" are repeated, while the ones labeled "Hospital" are not.

On Med 1, the ambulance will transmit on 468.000 while the hospital is on 463.000. Which is why you can hear the hospital, but not the ambulance.
 

jchappy

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I'm in Greenwich and I can hear an ambulance sign on perfectly on Med 5. When they transport and patch in with Greenwich Hospital on Med 1, the first "Greenwich go ahead" transmission is heard but after that it is all static and I can't hear anything the ambulance is saying to the hospital. Why is this, encryption? Do I need certain PL tones?
In this region, ambulance-to-hospital communications are not usually repeated. This is because communications between hospitals and ambulances used to be full duplex (transmit and receive simultaneously). Today, these communications are only half duplex (one person transmits at a time), but the patches are still not repeated. I'm not sure if this is for patient confidentiality or at the request of hospitals/EMS agencies (most other regions/states are repeated). This is probably accomplished using a "mixer", which enables the dispatcher to selectively allow the repeater input to be repeated (usually done to provide a tactical multi-agency channel for large-scale incidents). When the mixer is set not to repeat the hospital patches, it still keys the repeater but without any audio input, so that is the open carrier that you hear when the ambulance is transmitting. This is done so that others monitoring the channel are aware that the channel is in use.

You can sometimes hear MED 1 being used for purposes other than medical control or interoperability. For example, the closest MED 5 repeater is in Stamford. Sometimes, especially in backcountry Greenwich, the ambulances cannot reach the tower (mostly due to the terrain and foliage). In this case, the dispatcher may activate the MED 1 repeater (with the mixer on) on the tower at Greenwich Hospital to communicate with the ambulance. SW CMED has the ability to remotely activate any channel on any repeater on any tower.

Only once have I actually heard a full Greenwich Medic > Greenwich Hospital conversation while they're enroute. I was astounded! Why did I hear it that one time and never agin? Can someone help me fix this? I appreciate the help I get as always! :)
Do you have the MED 1 repeater input programmed into your scanner? If so, you'll only really hear anything if you're relatively close the the ambulance that is transmitting. Otherwise, you won't hear anything unless the dispatcher accidentally left the mixer on.
 

KB1JHU

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There's a button on the console to turn the repeaters on & off. Any of the med channel repeaters can be turned off or on. The repeaters used for patches are usually left off because there is no need to repeat a patient's condition at high power to scanner land.
 

zerg901

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Try 468.00 instead of 463.00 to hear the ambulance
 

Mork

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Yes please by what law?

No such statute exists. Point of fact, one could say that having the Med channels in the clear is a violation of HIPAA though in the thousands of times I've called Med Control I'd never revealed the identity of the patient.

I just visited Jacksonville where they just switched all their Medcom channels to encryption.
 

Mork

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As long as there is no patient name or specific personal information being given out, what is the big deal?

Manny

My understanding of the reasoning given was if you see the FD/EMS outside your neighbor's house and see them carried out and transported, one could deduce that the unit taking them was the one talking on the radio. Just another way Motrola makes another sale/upgrade. For a large city, it IS the most boring to scan. All of the PD is either encrypted or on LTR Passport.
 

izzyj4

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Curious what Law ? :confused:
It's not a state law, it's federal through the FCC. I do not remember the exactly how it is worded but all communications on the designated UHF MED channels have to be in the free and clear. I think there may be some information on the APCO website as well. I'll see if I can find it.

Also it is not a HIPPA violation in any way since a patient's personal information is not being transmitted to the hospital along withthier condition.
 

garys

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No such statute exists. Point of fact, one could say that having the Med channels in the clear is a violation of HIPAA though in the thousands of times I've called Med Control I'd never revealed the identity of the patient.

I just visited Jacksonville where they just switched all their Medcom channels to encryption.
It is not a HIPAA violation, the regulations specifically exclude emergency communications from the law. Whether you identify the patient by name or not. Around here all of the private ambulances give out patient names when they are doing inter facility transfers.

If Jacksonville is encrypting the radio traffic, it is because they don't know the law, it's that simple.
 

joetnymedic

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Hey Joe,
Are you talking something like this article? If so, it does say it doesn't say EMS "has to" encrypt, but then again I didn't read it to say they couldn't.

HIPAA Didn’t Kill the Radio Star | Public Safety Communications

That said, While I do monitor, I'm not a big fan of encryption, however being former EMS, I can understand not wanting to have someone listening to one of their neighbors info going OTA. I mean lets face it anyone who monitors in SC knows the designation for the AMR units here so whats to stop a nosey neighbor with a scanner from seeing the unit number and listening to the patch to the ER and then running around the neighborhood filling everyone in on the "scoop" as to what happened at the smith residence. On the other hand still, Correct me if I'm wrong but I believe that encryption takes more power from the radio, therefor shortening the distance the transmissions can travel. Like I said, I may be wrong on that, but that's just my belief. Hears my belief on this however and I'll probably get flamed for this but I'll take the chance in putting it out there. As long as the radio operator takes care as to the info he or she is putting ota, most times everything will be covered. I tend to look at things this way. There are ways of getting a message across without being obvious. When I first started EMS, AIDS was relatively new, so if we had an HIV/AIDS patient on board and they were on meds, due to the ryan white act, we wouldn't say the patient was positive, instead we would give the meds and let the ER know the PT was on say AZT, hence the message was delivered without saying it outright.. That's the way our instructors actually taught us back then. If I remember (And Joe, you'd know this better than anyone as will some old timers like myself). I believe there was one company who shall remain nameless that actually came up with a code (107A - if I remember) that let the crew know the PT was HIV/AIDS positive. That said, as long as whoever is calling into the ER is discrete, there shouldn't be a problem, nor a need for encryption and (I know this was the rule in NYS when I was working there) each rig had to have 2 types of commuication withthe hospital in case of failure by one of them. One was a radio and the second was a nextel or cell with a number directly to the ER which the number was programmed into. So if the crew is uncomfortable putting any info OTA, then hell use the cell. That simple. Do mistakes happen? Of course, but you deal with them. I know of a medic that had a celeb on a rig and called the ER via radio saying right over the air, "hey , you'll never guess who I'm coming in with (insert name) and he's puking up a storm. End of story, the medic never worked that town again. But for the most part, I think our responders are competent enough to know what to and not to say over the radio. but like I said that's just my opinion
 
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