Alpine Rescue Operation

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natedawg1604

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Alpine Rescue units are en-route emergent to some type of rescue call, I don't know the details but they are requesting a military helicopter and Mutual Aid from Park County SAR. Apparently they are looking for a ship to transport Alpine units to the scene. Anyone know what's going on? It kinda sounds like a mountain ridge extraction or something...
 

natedawg1604

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They are getting assistance from a Black Hawk with an external hoist, on-scene coms with the ship will be on MRA-1 (which seems to be a simplex channel, as best I can tell...) Apparently the Black Hawk is too heavy for Hospital Landing pads.
 
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natedawg1604

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Update: Apparently Lifeguard 1 is ALSO en-route and will be assisting with hospital transport after the rescue extraction, LZ will be at the summit of Guanella pass.
 

dw2872

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This is the info I have for MRA-1...

Mountain Rescue Association of Boulder County. The “MRA-1” channel is a simplex channel on 155.160 MHz and “MRA-2” is the repeater output for 155.235 MHz.

The radio feed here carries RMA-1 on the right speaker and RMA-2 on the left speaker:
https://www.broadcastify.com/listen/feed/4213

The communications heard on this feed (provided using two Bearcat 760XLT scanners located north of Erie, Colorado) primarily consists of the Rocky Mountain Rescue Group but other SAR operations may also use these frequencies since the Colorado Statewide SAR frequency is the same as MRA-1.

Other statewide SAR frequency users that can be heard on these frequencies are: Larimer County SAR, Alpine Rescue Team (Gilpin and Clear Creek Counties), El Paso County SAR, and Grand County SAR.


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natedawg1604

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This is the info I have for MRA-1...

Mountain Rescue Association of Boulder County. The “MRA-1” channel is a simplex channel on 155.160 MHz and “MRA-2” is the repeater output for 155.235 MHz.
....
Sent from my iPad using Tapatalk HD
Today/this evening Rocky Mountain Rescue has been working a call involving possible lost/stranded parties' ( I believe somewhere near the St. Vrain River). They've been using numerous channels including Rocky Mountain Rescue DTR and MRA-2. From Broomfield I've only been hearing one side of a strong signal from MRA-2 (155.235, 225.7 PL), as of now I can't hear it at all. The Broadcastify feed is broadcasting a lot of traffic on MRA-2, but just recently the field radios have dropped out and you can only hear MRA "Operations" base. It sounds like certain field units are losing VHF coverage.

Perhaps Rocky Mountain Rescue has an "operations base" with either a simplex Base Station or a half-duplex repeater? My understanding is that "full-duplex" repeaters broadcast all traffic at the same volume, so 155.235 must not be currently operating in full-duplex mode. Or, perhaps they have multiple linked repeaters and I'm only hearing one side of a repeater that is somehow simulcasting 155.235 from another site...
 

Spitfire8520

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Perhaps Rocky Mountain Rescue has an "operations base" with either a simplex Base Station or a half-duplex repeater? My understanding is that "full-duplex" repeaters broadcast all traffic at the same volume, so 155.235 must not be currently operating in full-duplex mode. Or, perhaps they have multiple linked repeaters and I'm only hearing one side of a repeater that is somehow simulcasting 155.235 from another site...
My thoughts from looking at their two licenses that they have granted to them (KYU980 and WQBX487) is that they have plenty of room to pick and choose the mode they operate MRA 2 on. Among those licensed for MRA 2 includes operation of a repeater for MRA 2, as well as fixed (FB) and temporary (FBT) base stations. What interests me is the odd FX1 stations for 465.6250 MHz which believe are typically licensed for repeater inputs and rather restricted number of MO units they have operating on that UHF frequency. Given that no one has noted the input frequency for the MRA 2 repeater makes me think that perhaps MRA 2 operates in mixed modes, normally operating as a simplex frequency (which explains lack of hearing the repeater in Broomfield) with an option of a crossband repeater being used for wide area coverage. The limited usage may indicate that it is restricted to someone in a leadership position for things like membership announcements or important operational messages.

The simulcasting thought isn't a bad idea either, given that WQBX487 shows another repeater in the Longmont area operating at 159.2325 MHz. However, the Longmont location does not have a license for a repeater on MRA 2. I don't think the online feed is streaming that since it remains unlisted by both the feed and RadioReference (likely due to lack of positive identification for its usage).

A slightly unrelated noted is that Boulder County does have at least one example of mixed usage operations on a frequency. It can be seen with the Boulder Fire Department which has a setup with repeater and simplex operations simultaneously on 155.7825 MHz (Fire-2/Tac-3). I've once heard the Battalion Chief having units switch to Tac-3 for a working fire (noted along with my inability to hear working companies), yet I was able to hear the Battalion Chief loud and clear as if she were operating on the Fire-2 repeater. Perhaps Boulder Fire Department used Rocky Mountain Rescue as an example for using repeaters to supplement operations without being dependent on them.

EDIT: I did some extensive searching of Rocky Mountain Rescue related things online as well as explored the KYU980 license thoroughly to try to figure out more about the MRA frequencies. It appears that Rocky Mountain Rescue has plans in 2002 to build a repeater system but was told that there were not sufficient VHF frequency pairs to allow them to do so at that time. They did note that they would be purchasing repeater equipment in 2002 with grant money they received. It appears that the license in 2002 only contained MRA 1 and MRA 2. They also mentioned adding "MRA 3" to the license for out of county use (misprint?), but no idea what they meant by that and it has never been mentioned since. They also mentioned "adding a new way of controlling or using the 1900 base station radio via a UHF link." Not too much has changed regarding the KYU980 license since then besides adding the UHF control frequency and the additional 159.2325 MHz frequency licenses sometime in 2004-2005. There was mention in 2005 of hearing Rocky Mountain Rescue on their UHF frequencies on portables on the forums.
 
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natedawg1604

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My thoughts from looking at their two licenses that they have granted to them (KYU980 and WQBX487) is that they have plenty of room to pick and choose the mode they operate MRA 2 on. Among those licensed for MRA 2 includes operation of a repeater for MRA 2, as well as fixed (FB) and temporary (FBT) base stations. What interests me is the odd FX1 stations for 465.6250 MHz which believe are typically licensed for repeater inputs and rather restricted number of MO units they have operating on that UHF frequency. Given that no one has noted the input frequency for the MRA 2 repeater makes me think that perhaps MRA 2 operates in mixed modes, normally operating as a simplex frequency (which explains lack of hearing the repeater in Broomfield) with an option of a crossband repeater being used for wide area coverage. The limited usage may indicate that it is restricted to someone in a leadership position for things like membership announcements or important operational messages.

The simulcasting thought isn't a bad idea either, given that WQBX487 shows another repeater in the Longmont area operating at 159.2325 MHz. However, the Longmont location does not have a license for a repeater on MRA 2. I don't think the online feed is streaming that since it remains unlisted by both the feed and RadioReference (likely due to lack of positive identification for its usage).

A slightly unrelated noted is that Boulder County does have at least one example of mixed usage operations on a frequency. It can be seen with the Boulder Fire Department which has a setup with repeater and simplex operations simultaneously on 155.7825 MHz (Fire-2/Tac-3). I've once heard the Battalion Chief having units switch to Tac-3 for a working fire (noted along with my inability to hear working companies), yet I was able to hear the Battalion Chief loud and clear as if she were operating on the Fire-2 repeater. Perhaps Boulder Fire Department used Rocky Mountain Rescue as an example for using repeaters to supplement operations without being dependent on them.

EDIT: I did some extensive searching of Rocky Mountain Rescue related things online as well as explored the KYU980 license thoroughly to try to figure out more about the MRA frequencies. It appears that Rocky Mountain Rescue has plans in 2002 to build a repeater system but was told that there were not sufficient VHF frequency pairs to allow them to do so at that time. They did note that they would be purchasing repeater equipment in 2002 with grant money they received. It appears that the license in 2002 only contained MRA 1 and MRA 2. They also mentioned adding "MRA 3" to the license for out of county use (misprint?), but no idea what they meant by that and it has never been mentioned since. They also mentioned "adding a new way of controlling or using the 1900 base station radio via a UHF link." Not too much has changed regarding the KYU980 license since then besides adding the UHF control frequency and the additional 159.2325 MHz frequency licenses sometime in 2004-2005. There was mention in 2005 of hearing Rocky Mountain Rescue on their UHF frequencies on portables on the forums.
Hmm, very interesting comments. While listening to the Feed for MRA-2 yesterday I repeatedly heard Operations Base announce "KYU980".
 

soundchaser

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Just a few tidbits.

I believe I've heard MRA2 also used in Talk-Around mode, where the mobile units bypass the repeater and transmit directly on the same frequency. They usually use the repeater at the start of a rescue, then switch to simplex mode when everybody is on scene.

Boulder County Red-5 (simplex) and Red-6 (repeater) were also used in the St. Vrain rescue. Also used yesterday was TGID 9556 on the state DTRS. MRA1 was supposedly used for comms between the helicopter and RMR units on the ground, but I'm far enough away I couldn't hear.

Scott Whitehead, who by day is the county's chief radio guy, is a member of RMR.

More info about the rescue:
Father, son hiking in North St. Vrain Canyon alert rescuers with reflective blanket - Boulder Daily Camera
 

natedawg1604

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Just a few tidbits.

I believe I've heard MRA2 also used in Talk-Around mode, where the mobile units bypass the repeater and transmit directly on the same frequency. They usually use the repeater at the start of a rescue, then switch to simplex mode when everybody is on scene.

....
Do you think they would change modes because they can't hit the repeater input freq. in certain areas?
 

soundchaser

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Do you think they would change modes because they can't hit the repeater input freq. in certain areas?
Yes, I would imagine there are many areas in the mountains (especially canyons) where it would be difficult to hit their repeater.

The reason I believe they are using talk around mode is that the signal strength varies depending on who is talking.
 
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