Question about radio waves.

[cstockmyer]

Ok so I know this is out of left field but I have to ask. Can you listen to normal AM/FM radio on a scanner? Or can you hear things like FERN or CLEER on a normal AM/FM radio? What's the difference in air the Peoples Republic Of Boulder PD or SO or some other non trunked/Digital system is on compared to 103.5FM the fox? Is there an easy way to explain that?

 

[Thayne]

There are mainly 2 things that radio receivers of any type have to match with what you want to listen to: Frequency range(s) and modulation type(s)
A scanner could pick up AM/FM broadcasts if it was designed to do it. As far as the other way around, probably not without some extra device to go with it. When I was a kid I had a converter that would convert VHF to broadcast band, but it cost about 30.00 and worked like it cost 10.00. Another thing is that scanners have to do so much without costing a fortune that they are full of necessary compromises, but still do remarkably well for the cost. I hope I didn't confuse you

 

[luke-1]

Ok so I know this is out of left field but I have to ask. Can you listen to normal AM/FM radio on a *******? Or can you hear things like FERN or CLEER on a normal AM/FM radio? What's the difference in air the Peoples Republic Of Boulder PD or SO or some other non trunked/Digital system is on compared to 103.5FM the fox? Is there an easy way to explain that?

The First part of your question-

FM radio broadcasts in "Wide FM" (WFM). Most Uniden radios , along with some others, will allow you to receive the FM band in WFM. So yes, you can listen to "The Fox".
Newer RS radios however, do not let you. They will only broadcast that band in "Narrow FM" (NFM)

The second part-
A "Normal" AM/FM radio is restricted to the AM and FM band. No one else but radio stations use those bands, so no.

Luke

 

[cstockmyer]

That makes it very clear, thanks!

I guess I am just confused, you can hear Denver radio stations all over Colorado, so why would it not be the other way around? To where the normal radio stations broadcast in Narrow FM, and Public Safety in Wide? With all the radio problems, like dead spots and so on, would it not be a better system? Or am I backwards? I guess I just thought that in a post 9/11 world we would need a way for radios to reach farther..again I could be backwards and wrong, and if that's they case, I tend to like my crow with some fries...

 

[evergreenwaterman]

Intersting thread. My first scanner was a transistor AM radio with a rubber band around this small unit about the size of a pager, with an antenna, that tuned into a frequency on the radio that broadcast the local police, Pueblo to be specific. I was hooked when I got to the incident before the cops on my bike. Some of you will remember....Dave

 

[greenthumb]

If one radio site covered the entire state, it would need to have considerably more than the 28 channels per site that the current releases of smartzone allow since all talk groups would be coming off of that one site. Additionally, broadcast radio stations are putting out somewhere in the kilowatt range of output power, whereas the trunked sites are putting out only about 100 watts (ERP). I also think that an additional reason that they have to be wide FM is due to that high power output. I could be wrong, but I don't believe that several kilowatts of power could be jammed into a 20 kc channel in FM. The biggest reason for the wide bandwidth is for the fidelity of the transmission. The better the transmission audio quality, the more bandwidth it will require. Finally, if that one site would go down or become disabled, the whole system would be gone. It's better to have sites scattered all around "backfilling" each other to increase capacity and redundancy. Much like a cell phone network.

 

[luke-1]

Just thinking here-

First off, yes you are right. The lower the freq. the farther it will travel, under normal circumstances. The problem is Denver PD does not want to listen to Salina KS PD.

There are not enough freqs. or even tones to give everyone their own. So they use higher ones, that don't travel as far, and use repeaters or other methods to patch agencies together on an "as needed" basis.

Also a power output difference. Radio stations can put out a lot more power than a pac-set.

As far as dead spots, without an antenna on the top of every mountain, they will be there

Keep in mind there are "Nationwide" emergency freqs. also

I'm sure there are a lot of other reasons- Gov.,FCC, Money etc.

Like I said, just thinking

Luke

 

[cstockmyer]

So how far does a radio signal go? Lets take CLEER for grins, with CLEER can Burlington PD way out there on the eastern planes, talk to lets say Grand Junction? Or is that what the state DTRS system is going to be for? So any Department can talk to any other dept no matter the distance?

Then just for grins, why can't Departments use High Def Radio? Or do they?

 

[luke-1]

Actually "CLEER" is a relatively high frequency (actually Ultra high UHF), so no it would not travel that far. It is linked into most trunking systems in the metro area to help it work better. Otherwise, it would probably not make it from Aurora to Lakewood.

The State DTRS has their own versions of "CLEER" with Network First, MAC TG's etc.

A digital system, I would think, would be considered High Def. There probably is a High Def. digital radio system, but that is beyond me.

Luke

 

[cstockmyer]

Actually "CLEER" is a relatively high frequency (actually Ultra high UHF), so no it would not travel that far. It is linked into most trunking systems in the metro area to help it work better. Otherwise, it would probably not make it from Aurora to Lakewood.

The State DTRS has their own versions of "CLEER" with Network First, MAC TG's etc.

A digital system, I would think, would be considered High Def. There probably is a High Def. digital radio system, but that is beyond me.

Luke

Thanks Luke!

 

[luke-1]

You need to add a Pro-96 to your list Charles

The State DTRS is pretty cool

Luke

 

[cstockmyer]

You need to add a Pro-96 to your list Charles

The State DTRS is pretty cool

Luke

Oh if I could I would in a heartbeat Luke, I am amazed I found the money to get a pro-2005.

 

[rick521]

Ha Ha

Just thinking here-

First off, yes you are right. The lower the freq. the farther it will travel, under normal circumstances. The problem is Denver PD does not want to listen to Salina KS PD.
Luke

What Denver PD does not want to listen to us????? I am shocked!!!!

On the other hand, I do remember when we were on low band in Salina, and sent a deputy to the pan handle of Florida and he talked to us from down there. Skip was awesome on low band.

 

[datainmotion]

What Denver PD does not want to listen to us????? I am shocked!!!!

hehehehehehehehehe...I almost cross-posted this to you guys!

 

[rc104a]

In 1973-74 I lived in Scottsbluff NE. Denver PD was on 159.09 and was being rebroadcast all over western NE on 42.46 from the 159.09 Rushville-Gering link.