analog vs digital radios
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analog vs digital radios
Hi guys, i dont want to be repetitive on a topic, but i searched the forums and didnt find anything of my particular questioning. so heres my post. my town got a grant to purchase new digital motorola radios, were currently using ht1250s, and mcs2000 radios which im sure are analog. what im asking is, obviously analog and digital are two different things, but whats the benefit of digital? also, what about the compatibility between the two, can the ht1250's talk to the new digital radios (i forgot the name of them, but they are motorola p something radios. and can the mcs2000s hear the digital transmissions? let me know. thanks.
- Tom in D.C.
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Re: analog vs digital radios
Without taking sides or making positive or negative comments:
1. Having a digital radio lets you talk to other people on their digital systems. Like the fire crew from the next county which is on a digital system and you're still on an analog system. This is called interoperability and there's been a ton of stuff written on this Board about the subject, so do a search for it.
2. The digital radios can do both digital and analog operation.
3. An analog radio can receive and transmit analog only.
4. A digital radio can be set to receive both analog and digital on the same channel but it will only transmit in the mode for which it's been programmed. This is called "mixed mode."
5. A trunked digital system, which you didn't ask about but which is the most common form of departmental digital comms these days, won't work at all with an analog system.
6. Your analog radios will hear only a continuous burst of noise on the channel when a digital signal is being transmitted.
Post the model number of your new radios and someone can give you some additional information, but when you get that information do a Board search first to see what's already been posted.
1. Having a digital radio lets you talk to other people on their digital systems. Like the fire crew from the next county which is on a digital system and you're still on an analog system. This is called interoperability and there's been a ton of stuff written on this Board about the subject, so do a search for it.
2. The digital radios can do both digital and analog operation.
3. An analog radio can receive and transmit analog only.
4. A digital radio can be set to receive both analog and digital on the same channel but it will only transmit in the mode for which it's been programmed. This is called "mixed mode."
5. A trunked digital system, which you didn't ask about but which is the most common form of departmental digital comms these days, won't work at all with an analog system.
6. Your analog radios will hear only a continuous burst of noise on the channel when a digital signal is being transmitted.
Post the model number of your new radios and someone can give you some additional information, but when you get that information do a Board search first to see what's already been posted.
Tom in D.C.
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that children may not be sent by parcel post.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
Re: analog vs digital radios
There are few other topics that will generate more passionate arguments amongst "radio folks" than the debate over which is better - analog or digital. You are going to find some very strong opinions both ways. If you wanted to print on paper all the internet debates on this site or others about this subject, you probably would not be able to afford cost of the paper and ink.
You did not specify if you are only getting digital subscriber radios or if you are building out a complete system or if it is for fire/rescue or LEA. So, are you building a digital conventional or trunked system, going onto an existing system that operates in your area (like a regional or statewide system), or are you only buying digital radios to use on an existing conventional analog system?
Some debate on the use of digital in conventional systems center on range - which is better. Some folks feel that the digital systems provide better overall audio quality over the service area because as long as there is recoverable data in the signal, then the radios will convert that to clear audio until you reach that magic point where the signal is so weak that the radios no longer receive enough data and that's it - your done. On the other hand, in analog, as signal levels drop, the audio fades into the background noise and makes it difficult to copy transmissions. A skilled radio operator can probably copy noisy signals in analog on transmissions that would be below the signal levels required for the digital radio to work, but for the average user, digital will probably provide slightly better usable range on identical systems in identical conditions.
If your new digital radios are being used on the same frequencies as your MCS2000s and HT1250s, then they will be able to talk to each other as long as the new digital radios are programmed to transmit and receive in analog with the same settings as your old radios (frequency, tone, & bandwidth). Your old radios will not be usable on any digital system that you build. If this is a fire dept. system, there is a great deal of information about the incompatibility of the digital radio vocoder and noises commonly found on the fire ground. It just can't be processed and nothing intelligible comes out the other end. Your people will have to be trained to be aware of this and how to try and abate some of the background noise to be understood.
If your are looking to build a complete digital trunked system, consider this:
The costs of digital trunked systems are astronomically higher than conventional analog. We went from an annual operating budget of about $50,000/yr for maintenance, operation, and scheduled replacement when we were using our conventional VHF system. Now we budget about $1,000,000 per year. We owned our old system, but now we pay monthly subscriber fees per radio to the local public utility that owns the trunked system. Scheduled replacement of radios is considerably higher, service fees are higher, and the aforementioned subscribers fees are something we just didn't have before.
What did we get?
The trunked system works a little better in some places, and a little worse than other places than our old system. We went from six repeated channels and nine simplex channels to 42 trunked talkgroups. On the old system we used one channel for dispatch, two repeaters for operations (assigned in real time), and simplex channels for on-scene coordination. Since we still only have three operator positions in dispatch, and only three dispatchers on duty, we still only use one talkgroup for dispatch and two talkgroups for operations, assigned in real time. We've lost the capability for simplex on-scene coordination, and that is a huge problem. We have the capability to talk to other agencies (LEA) in our county - but we were able to do that in the past with a console patch. This interoperability is almost never used, BTW. As far as interoperability with adjoining counties, well, in Florida we have the Motobridge, so that is all done by infrastructure so interoperability is not an added benefit to us. If we leave our service area, we have to switch to the mutual aid channels, but in Florida mutual aid infrastructure exists on VHF and UHF as well. We still have to carry VHF radios to interoperate with the Division of Forestry because they use VHF simplex channels for on scene operations that are not supported by infrastructure. The individual unit ID is nice, but our old system had the capability, we just didn't use it. Same for the emergency call feature, although when a radio is in emergency, it has priority on the system over all other radios which is excellent. Conventional systems don't do that. There is the private call feature, but we don't use that either. Control - the only people who have access to the system are people who are supposed to be on the system. No longer can a person go buy his own radio and use it and that is real nice. We were not needing to add additional channels and there wasn't any frequency congestion in our area.
So for roughly $950,000 more per year, we get access control and emergency priority and that's about it.
If you are needing to add more channels and the spectrum is not available, or need the capability of encryption, then a digital trunked system might be a good investment. If you are simply replacing an existing system and will not be making any operational changes, then perhaps it might be more than you need to spend. I fail to see where the cost benefit is with the system we have. It's just not there.
I'm sure you will receive contrasting points of view.
Regards,
Robert
You did not specify if you are only getting digital subscriber radios or if you are building out a complete system or if it is for fire/rescue or LEA. So, are you building a digital conventional or trunked system, going onto an existing system that operates in your area (like a regional or statewide system), or are you only buying digital radios to use on an existing conventional analog system?
Some debate on the use of digital in conventional systems center on range - which is better. Some folks feel that the digital systems provide better overall audio quality over the service area because as long as there is recoverable data in the signal, then the radios will convert that to clear audio until you reach that magic point where the signal is so weak that the radios no longer receive enough data and that's it - your done. On the other hand, in analog, as signal levels drop, the audio fades into the background noise and makes it difficult to copy transmissions. A skilled radio operator can probably copy noisy signals in analog on transmissions that would be below the signal levels required for the digital radio to work, but for the average user, digital will probably provide slightly better usable range on identical systems in identical conditions.
If your new digital radios are being used on the same frequencies as your MCS2000s and HT1250s, then they will be able to talk to each other as long as the new digital radios are programmed to transmit and receive in analog with the same settings as your old radios (frequency, tone, & bandwidth). Your old radios will not be usable on any digital system that you build. If this is a fire dept. system, there is a great deal of information about the incompatibility of the digital radio vocoder and noises commonly found on the fire ground. It just can't be processed and nothing intelligible comes out the other end. Your people will have to be trained to be aware of this and how to try and abate some of the background noise to be understood.
If your are looking to build a complete digital trunked system, consider this:
The costs of digital trunked systems are astronomically higher than conventional analog. We went from an annual operating budget of about $50,000/yr for maintenance, operation, and scheduled replacement when we were using our conventional VHF system. Now we budget about $1,000,000 per year. We owned our old system, but now we pay monthly subscriber fees per radio to the local public utility that owns the trunked system. Scheduled replacement of radios is considerably higher, service fees are higher, and the aforementioned subscribers fees are something we just didn't have before.
What did we get?
The trunked system works a little better in some places, and a little worse than other places than our old system. We went from six repeated channels and nine simplex channels to 42 trunked talkgroups. On the old system we used one channel for dispatch, two repeaters for operations (assigned in real time), and simplex channels for on-scene coordination. Since we still only have three operator positions in dispatch, and only three dispatchers on duty, we still only use one talkgroup for dispatch and two talkgroups for operations, assigned in real time. We've lost the capability for simplex on-scene coordination, and that is a huge problem. We have the capability to talk to other agencies (LEA) in our county - but we were able to do that in the past with a console patch. This interoperability is almost never used, BTW. As far as interoperability with adjoining counties, well, in Florida we have the Motobridge, so that is all done by infrastructure so interoperability is not an added benefit to us. If we leave our service area, we have to switch to the mutual aid channels, but in Florida mutual aid infrastructure exists on VHF and UHF as well. We still have to carry VHF radios to interoperate with the Division of Forestry because they use VHF simplex channels for on scene operations that are not supported by infrastructure. The individual unit ID is nice, but our old system had the capability, we just didn't use it. Same for the emergency call feature, although when a radio is in emergency, it has priority on the system over all other radios which is excellent. Conventional systems don't do that. There is the private call feature, but we don't use that either. Control - the only people who have access to the system are people who are supposed to be on the system. No longer can a person go buy his own radio and use it and that is real nice. We were not needing to add additional channels and there wasn't any frequency congestion in our area.
So for roughly $950,000 more per year, we get access control and emergency priority and that's about it.
If you are needing to add more channels and the spectrum is not available, or need the capability of encryption, then a digital trunked system might be a good investment. If you are simply replacing an existing system and will not be making any operational changes, then perhaps it might be more than you need to spend. I fail to see where the cost benefit is with the system we have. It's just not there.
I'm sure you will receive contrasting points of view.
Regards,
Robert
Wyrd bið ful ãræd, Fate is inexorable...
- SYNTORX71MAN
- Posts: 520
- Joined: Sun Mar 03, 2002 4:00 pm
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Re: analog vs digital radios
Very well spoken Robert, and I'll add this: With our Digital system when you are out in a fringe area and try to transmit, all we get is a continous beep tone and a out of range on the radio display, be it portable or mobile unit. When the system was analog at least the dispatchers heard a weak or scratchy message when an officer or firefighter was in trouble. Also the transmissions pick uncanny times to go digital, you hear the officers voice fine and then, beep and boops followed by other untelligable garbage follows..LOL The Pros we got with the system were #1 Fed Govt Money from FEMA for New Radios: Portables and Mobiles. Motorola dealers as well as big M got a big statewide contract. We gained the ability to hinder those nasty scanner enthusists who now have to purchase $500.00 scanners to listen to the system in order to call 911 and provide tips on the bad guys. We never had a trepass or jamming issue with unauthorized users. But the powers that be swallowed the M's sales pitch hook, line and sinker. For the most part the old system worked great, it just needed a few extra repeaters set up in fringe areas. But the high ups people like to purchase the biggest and the best. I will say this, If it were NOT for the Federal grants for the new radios I am sure we would still be on the old system. But GPSing is coming soon so no more Unit 22 whats your location....LOL Ya better be there....LMAO
Re: analog vs digital radios
Check your grant funding carefully. Most these days require two major things that people overlook or are confused about:
#1-All radio equipment must support narrowbanding (12.5) ((which 99.9999 have been able to do for quite some time now))
#2-Must be able to support digital (IMBE) P25 signalling (ASTRO). The keyword here is "able to support".*
*I think Matt here on the board can go into some detail, but in short, if you buy an XTS radio with just the analog only option, that should fly. You do not need to buy the digital option at the time of purchase. This is because the radio can be flash upgraded to IMBE down the road when you choose to. IIRC, many orginal grants after 9/11 required digital operation but that has since been downgraded to above (from the ones that I have seen).
Any new trunked system from Motorola will be a 9600 APCO25 compliant trunked system. That allow will set you back mega dollars. If your asking that question here, then your already out of your relm of knowledge and responsibility.
If your small down america (+/-50,000), then a trunked system is not for you. A properly designed conventional analog or trunked could work well for you. Keep in mind with your neighbors who may be coming into your town, and your workers going to those other towns for mutual aid. If your on UHF and everyone is on VHF...consider seaching for available VHF channels. Share resources.
There can be quite a bit of discussion on this, but without hard facts on what you plan on doing with this money (amount?), which your demographics are, number of users, its still just speculation.
#1-All radio equipment must support narrowbanding (12.5) ((which 99.9999 have been able to do for quite some time now))
#2-Must be able to support digital (IMBE) P25 signalling (ASTRO). The keyword here is "able to support".*
*I think Matt here on the board can go into some detail, but in short, if you buy an XTS radio with just the analog only option, that should fly. You do not need to buy the digital option at the time of purchase. This is because the radio can be flash upgraded to IMBE down the road when you choose to. IIRC, many orginal grants after 9/11 required digital operation but that has since been downgraded to above (from the ones that I have seen).
Any new trunked system from Motorola will be a 9600 APCO25 compliant trunked system. That allow will set you back mega dollars. If your asking that question here, then your already out of your relm of knowledge and responsibility.
If your small down america (+/-50,000), then a trunked system is not for you. A properly designed conventional analog or trunked could work well for you. Keep in mind with your neighbors who may be coming into your town, and your workers going to those other towns for mutual aid. If your on UHF and everyone is on VHF...consider seaching for available VHF channels. Share resources.
There can be quite a bit of discussion on this, but without hard facts on what you plan on doing with this money (amount?), which your demographics are, number of users, its still just speculation.
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Re: analog vs digital radios
PJ brings up a very good point about population size, and weather to go analog vs. digital. I live in CT, and 99% of the local LEO's around my area are all UHF Analog (some 800MHZ, and VHF), but hardly anyone is digital. Also most of the towns are hovering around the 60,000 +/- population mark. The State Police is on an 800MHZ Digital Trunked system, however digital in CT is far and few between. (Please someone enlighten me if I'm wrong on this. I know Glastonbury is 800MHZ as well, but I don't know if they are P25 or not).
Any-who, sorry to stray off topic, but to the OP, if you are going digital, as mentioned you WILL need new radios. Your HT1250 will NOT work with a digital system.
Any-who, sorry to stray off topic, but to the OP, if you are going digital, as mentioned you WILL need new radios. Your HT1250 will NOT work with a digital system.
Re: analog vs digital radios
Also, don't forget that if you decide to switch to digital using your current licensed freq(s), keep in mind that you'll have modify your license with the correct emission designators before you start using digital mode.
Re: analog vs digital radios
If the radio is digital and starts with a "P" than it is likely M/A-COM and not Motorola. If this has been in the works for a while that would further the speculation since New York State was operating a statewide M/A-COM OpenSky network until they just recently dumped M/A-COM based on an argument that they did not perform to the contract terms.