OK guys. I'm in a dilemma. Over the past year and a half I have been working to aquire the frequencies for the fire department I am on in order to construct a repeater. Back then everything was fine and the group agreed a repeater would help us out. We have since aquired those frequencies and now some of the group wants to back out of getting a repeater.
What advantages can I suggest that would help my case. I know the increased radio range is a major plus, but are there others? Is there a rule of thumb of distances from portable to portable vs portable to repeater to portable or mobile to repeater to mobile etc.
I've got to convince some people who have been on the department since 1958. Since they didn't have a repeater then and fought fire fine why would we need it know?
We are in the VHF High-band range and luckily aquired a wide-bandwidth repeater pair that will work in our existing radios.
Any and all suggestions would be appreciated.
How can I convince them we need a repeater
Moderator: Queue Moderator
Actually, "increased radio range" is not one of the advantages of a repeater in a fire situation, and the use of repeaters in fire situations should be carefully thought out.
A repeater does not increase the range of communications between field units (mobiles and portables; sometimes referred to as "subscriber units") and dispatch (or Fire Alarm): talk out range will be identical, because the same high site transmitter is used, and talk in range will be the same because the same receiver or (in a voted system) receivers will be the same.
What a repeater does is increase in the range over which two subscriber units can talk directly to one another; if both are in range of the repeater, then they are in effective range of one another.
In a police setting, subscriber-to-subscriber traffic is routine and, on occasion, critical. In a fire situation, however, 99% of all traffic is either between apparatus and Fire Alarm, or between or among units on the fireground. By definition, the fireground is a compact area, and unit-to-unit talkability on the fireground may often be better on simplex than via the repeater.
There is a downside to repeaterizing, particular in the fire service. Because subscriber units on the "repeat" channel of a repeaterized system transmit on a different frequency than the one they listen to, if a member is trapped in a location from which it is difficult to make it to the repeater--such as a basement--then unless he keeps enough of his training in mind to switch to the "direct" channel, he isn't going to get any help. Depending on circumstances, that could be asking a lot.
At a minimum, going to a repeater in the fire service means writing new training procedures, holding more classes, and doing more commo drills.
On the other hand, if the system operates simplex, then when our hypothesized jake-in-trouble calls out, the companies on the sidewalk will almost certainly hear him, even if Fire Alarm cannot. There is no need to remember about "direct" when danger is close and the adrenaline is flowing wide open.
The correlative limitation in trunked systems--which do not include the option of transmitting on "direct"--has led to NFPA 1221 barring the use of trunked channels on the fireground.
Something to think about. I know that the recent trend among fire departments is to repeaterize, and there are point to consider on both sides of the question. But do not mislead yourself (or anyone else) by an oversimplification such as that repeaters increase range.
A repeater does not increase the range of communications between field units (mobiles and portables; sometimes referred to as "subscriber units") and dispatch (or Fire Alarm): talk out range will be identical, because the same high site transmitter is used, and talk in range will be the same because the same receiver or (in a voted system) receivers will be the same.
What a repeater does is increase in the range over which two subscriber units can talk directly to one another; if both are in range of the repeater, then they are in effective range of one another.
In a police setting, subscriber-to-subscriber traffic is routine and, on occasion, critical. In a fire situation, however, 99% of all traffic is either between apparatus and Fire Alarm, or between or among units on the fireground. By definition, the fireground is a compact area, and unit-to-unit talkability on the fireground may often be better on simplex than via the repeater.
There is a downside to repeaterizing, particular in the fire service. Because subscriber units on the "repeat" channel of a repeaterized system transmit on a different frequency than the one they listen to, if a member is trapped in a location from which it is difficult to make it to the repeater--such as a basement--then unless he keeps enough of his training in mind to switch to the "direct" channel, he isn't going to get any help. Depending on circumstances, that could be asking a lot.
At a minimum, going to a repeater in the fire service means writing new training procedures, holding more classes, and doing more commo drills.
On the other hand, if the system operates simplex, then when our hypothesized jake-in-trouble calls out, the companies on the sidewalk will almost certainly hear him, even if Fire Alarm cannot. There is no need to remember about "direct" when danger is close and the adrenaline is flowing wide open.
The correlative limitation in trunked systems--which do not include the option of transmitting on "direct"--has led to NFPA 1221 barring the use of trunked channels on the fireground.
Something to think about. I know that the recent trend among fire departments is to repeaterize, and there are point to consider on both sides of the question. But do not mislead yourself (or anyone else) by an oversimplification such as that repeaters increase range.
I agree with RKG except for the part about units not talking to each other over distances.
It depends on what you are trying to do. Yes, all on scene tactical communiations should be done on a direct, fireground channel (SOG quote: "Upon arrival on scene, all units will switch to and operate on channel two"). This should not be the talkaround of the repeater channel. Poor jake-in-trouble might not be heard at the ICP over the repeater transmitting at the same time. This should be done on a specific fire ground channel, but one that dispatch can transmit and receive on in case an evacuation alarm needs to be transmitted. Remember the tapes from the Hackensack fire, where dispatch could hear the trapped firefighters but command didn't.
If the IC is trying to run a wildland fire with his division supervisors operating 10 miles from the ICP over a ridgeline, then a repeater is needed.
If the IC is trying to direct the second due company that is responding from 15 miles away, then a repeater is needed.
If the District Chief is trying to monitor and track the operations of companies operating on single company calls over a large fire district, then a repeater is needed.
If the IC is trying to communicate with Division A that is in the basement of an appartment building, then they had better both be on direct. A portable in a basement might be able to talk from where it is in the basement to the IC who is literally 200 feet way, but would probably never make it to the repeater receiver 10 miles away. Division A probably won't be able to hear that same repeater as he is crouched down on the basement floor laying on top of his radio.
If your district is small, and you are able to talk on simplex already, then it would be kind of hard to justify the expense of frequency coordination & licensing (you will have to redo your license, you are changing the technical specifications of your system), equipment purchase & installation, shop fees to reprogram radios, etc. It really wouldn't improve anything.
To answer your question about how far you can talk through a repeater:
Anywhere from where your base station can hear you now to anywhere else your base station can hear you now, unless you are planning to increase your antenna height.
Our agency is a countywide fire/rescue service. We've had repeaters for years (trunked now) and it would be difficult for us to operate effectively without the ability to hear each other many miles away.
Like I said, it depends on what you are trying to do.
YMMV
Robert
It depends on what you are trying to do. Yes, all on scene tactical communiations should be done on a direct, fireground channel (SOG quote: "Upon arrival on scene, all units will switch to and operate on channel two"). This should not be the talkaround of the repeater channel. Poor jake-in-trouble might not be heard at the ICP over the repeater transmitting at the same time. This should be done on a specific fire ground channel, but one that dispatch can transmit and receive on in case an evacuation alarm needs to be transmitted. Remember the tapes from the Hackensack fire, where dispatch could hear the trapped firefighters but command didn't.
If the IC is trying to run a wildland fire with his division supervisors operating 10 miles from the ICP over a ridgeline, then a repeater is needed.
If the IC is trying to direct the second due company that is responding from 15 miles away, then a repeater is needed.
If the District Chief is trying to monitor and track the operations of companies operating on single company calls over a large fire district, then a repeater is needed.
If the IC is trying to communicate with Division A that is in the basement of an appartment building, then they had better both be on direct. A portable in a basement might be able to talk from where it is in the basement to the IC who is literally 200 feet way, but would probably never make it to the repeater receiver 10 miles away. Division A probably won't be able to hear that same repeater as he is crouched down on the basement floor laying on top of his radio.
If your district is small, and you are able to talk on simplex already, then it would be kind of hard to justify the expense of frequency coordination & licensing (you will have to redo your license, you are changing the technical specifications of your system), equipment purchase & installation, shop fees to reprogram radios, etc. It really wouldn't improve anything.
To answer your question about how far you can talk through a repeater:
Anywhere from where your base station can hear you now to anywhere else your base station can hear you now, unless you are planning to increase your antenna height.
Our agency is a countywide fire/rescue service. We've had repeaters for years (trunked now) and it would be difficult for us to operate effectively without the ability to hear each other many miles away.
Like I said, it depends on what you are trying to do.
YMMV
Robert
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Birken Vogt
- Posts: 262
- Joined: Thu Nov 10, 2005 7:53 pm
Asking for a repeater to allow for better fire fighting is a poor aurgument. In most all cases, on sceene fire fighting should be on a simplex channel (NFPA mandates this).
Having a repeater for better dispatch coverage (assuming the repeater is located in a better location for the coverage desired) is a good argument.
Most departments that I know that have repeater access rarly uses it at a sceene. It is always simplex. The portables never come off the simplex channel.
Having a repeater for better dispatch coverage (assuming the repeater is located in a better location for the coverage desired) is a good argument.
Most departments that I know that have repeater access rarly uses it at a sceene. It is always simplex. The portables never come off the simplex channel.
We had a incident here in the Verdugo Fire district last week. A vehicle over the side of a canyon, and good ole Verdugo dispatched evey thing, Sierra Madre VFD, Arcadia FD, LA County and what a mess. Several other agencies had to come too complicating communications.
Sierra Madre VFD is first on scene and their VHF simplex worked quite well.
This canyon, Santa Anita runs north from Arcadia into the San Gabriel mountians... Guess where the UHF 470 repeater Verdugo assigned everyone to is located, some 8 miles WEST on top of the same mountain range...no communications. Verdugo requested everyone go to another UHF repeater, but that one is in about the same location... PISS poor comms.
They switched to another repeater, now realize that everyone on scene can see each other, and and that one is located on the western edge of Monrovia some 3 miles SE sorta line of sight and 800 feet lower than the road in the canyon. Still very piss poor comms.
The search/recovery team switched to Direct on the same freq as the UHF 484 repeater in Monrovia and had a hell of a time talking from 150 feet below the road to the IC on the road. The IC stayed on the repeater.. Seems Verdugo likes to hear what is going on.
The Verdugo dispatch still had the third repeater , Monrovia repeater, selected with the main dispatch for 8 citys..... jamming the S & R effort.
Long and short, the S & R had to switch the VHF SAR, 155.16 channel for comms.
Use a seperate portable only (limmited power) frequency for fire and rescue opperations on scene. This way you do not get jammed out by the repeater, or your distant neighbors.
Sierra Madre VFD is first on scene and their VHF simplex worked quite well.
This canyon, Santa Anita runs north from Arcadia into the San Gabriel mountians... Guess where the UHF 470 repeater Verdugo assigned everyone to is located, some 8 miles WEST on top of the same mountain range...no communications. Verdugo requested everyone go to another UHF repeater, but that one is in about the same location... PISS poor comms.
They switched to another repeater, now realize that everyone on scene can see each other, and and that one is located on the western edge of Monrovia some 3 miles SE sorta line of sight and 800 feet lower than the road in the canyon. Still very piss poor comms.
The search/recovery team switched to Direct on the same freq as the UHF 484 repeater in Monrovia and had a hell of a time talking from 150 feet below the road to the IC on the road. The IC stayed on the repeater.. Seems Verdugo likes to hear what is going on.
The Verdugo dispatch still had the third repeater , Monrovia repeater, selected with the main dispatch for 8 citys..... jamming the S & R effort.
Long and short, the S & R had to switch the VHF SAR, 155.16 channel for comms.
Use a seperate portable only (limmited power) frequency for fire and rescue opperations on scene. This way you do not get jammed out by the repeater, or your distant neighbors.
I should point out my Northeastern bias: I was thinking only of the urban firefighting that I'm familiar with and not widespread outside fires such as Western folks encounter. Notwithstanding, for the few times when subscriber-to-subscriber messages have to be transmitted over greater-than-simplex distances, I'd rely on FAO "echo."
I'll second Birken's comments.
Having a repeater for enroute coordination can be extremely helpful, especially in rural areas where you have volunteers responding from locations several miles apart. The IC can effectively coordinate who goes where, (send some people direct to the scene, others to the station for equipment, etc.) even though everyone is using portable radios. Without a repeater this isn't possible. Once units arrive on scene, they should switch to a simplex fireground frequency. This works extremely well, and is used extensively where I'm originally from (northern Wisconsin). Where I live now everything is simplex. It works, but I often find myself wishing we had a good countywide repeater system for dispatch.
Andy
Having a repeater for enroute coordination can be extremely helpful, especially in rural areas where you have volunteers responding from locations several miles apart. The IC can effectively coordinate who goes where, (send some people direct to the scene, others to the station for equipment, etc.) even though everyone is using portable radios. Without a repeater this isn't possible. Once units arrive on scene, they should switch to a simplex fireground frequency. This works extremely well, and is used extensively where I'm originally from (northern Wisconsin). Where I live now everything is simplex. It works, but I often find myself wishing we had a good countywide repeater system for dispatch.
Andy
Thanks for all the help so far. I should have clarified a few things in my first post. The repeater is NOT going to be used for fireground communications. However we were planning to use the direct side of the repeater for fireground communications. From the posts I read, this doesn't seem to be the best thing. We are a volunteer organization, and one of my key reasons for a repeater is so we could know who was going to the station to get what. In other words the repeater will help us in our response to a call. The repeater is going to cost an estimated $6500.00. I guess I will argue that the repeater will help our response TO a call, not necessary AT a call, however a better response TO a call will lead to a better response AT a call.
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Birken Vogt
- Posts: 262
- Joined: Thu Nov 10, 2005 7:53 pm
You're darn right it will. Where are you located. I bet your state has mutual aid type frequencies they will let you use for fireground simplex communications so you don't have to get another license. Like for instance here we have 154.280, 154.265 and 154.295 which are called White Fire 1 thru 3. They are used in a great many rural fire departments in California and some other states (though the name may be different) as a primary fireground tactical, including ours. Since they are simplex, and usually on HTs, the chances of interference getting very far are low so it doesn't take a whole lot of channels to serve a great many departments, i.e. they can be recycled a lot.
Birken
Birken
There are pros and cons to using the repeater output frequency as the fireground channel. The main advantage is that everyone is listening to the same frequency, so it may help you avoid the "I was on the wrong channel" problem. The main disadvantage is that a unit that is too far away from the fire scene may not hear fireground traffic and key up the repeater, causing interference to the fireground communications. It's certainly wise to have the repeater output as an available channel (either as a seperate channel or by using the "Talkaround" mode), but you may not want to use it as your primary fireground channel. Weigh the pros and cons before deciding.
Andy
Andy