"Narrowbanding" and Ameatur Radios

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BonziBuddy

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I use my Amateur radio also as scanner for public safety. Will the FCC mandated switch for public safety make it impossible to continue to monitor on a ham radio? Are there any mobile ham radios that have that channel spacing?
 

stevelton

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Wont make it impossible, but you probably wont get the audio quality that you may be used to.

If the frequency that the agency is using narrowband on is one that falls on the channel step that will program into a ham radio, then you may just notice a somewhat less amount of audio coming from your speaker. But if the frequency cannot be set on the amateur radio, you may be stuck trying to receive it slightly off frequency, like only 2.5khz. Then you will have the weaker audio, and a slight off frequency distortion, but you "should" still be able to understand what is being said.

Steven
 

zz0468

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Are there any mobile ham radios that have that channel spacing?

It's more than just channel spacing. In narrow band FM, the transmitter deviation is 2.5 KHz, vs 5 KHz for typical amateur FM, and what's now become known as "wideband". In order to properly receive narrowband, that would involve a different IF filter in the receiver. Many recent commercial radios have the ability to switch between wide and narrowband as needed, but I'm not yet aware of any amateur radios with that capability.
 

kilowa22

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I use my Amateur radio also as scanner for public safety. Will the FCC mandated switch for public safety make it impossible to continue to monitor on a ham radio? Are there any mobile ham radios that have that channel spacing?

It depends on the capability of the radio you have. Many recent Ham HT's already support NFM 2.5 kHz deviation because in Europe and Asia the band plans already use narrow banding since repeater space is tight.
 

SOFA_KING

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It's more than just channel spacing. In narrow band FM, the transmitter deviation is 2.5 KHz, vs 5 KHz for typical amateur FM, and what's now become known as "wideband". In order to properly receive narrowband, that would involve a different IF filter in the receiver. Many recent commercial radios have the ability to switch between wide and narrowband as needed, but I'm not yet aware of any amateur radios with that capability.

My Icom ID880H has true narrow band FM. So does my IC91 AD portable. I think you will find narrow FM on more modern radios, but I have not been following all the newer offerings. It might be something to look for if you are buying a new radio.
 

zz0468

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My Icom ID880H has true narrow band FM. So does my IC91 AD portable. I think you will find narrow FM on more modern radios, but I have not been following all the newer offerings. It might be something to look for if you are buying a new radio.

Ah, very good. I looked at the specs for both radios and they do indeed do 5/2.5 KHz deviation. Thanks for pointing those out.

Any others? I clearly need to catch up on what's out there!
 

N8IAA

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The only current ham radio that has the 7.5Khz step is the Kenwood TM-271A. Almost all of the new ht's have the narrow band setting.
Larry
 

n1das

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Many recent commercial radios have the ability to switch between wide and narrowband as needed, but I'm not yet aware of any amateur radios with that capability.

Commercial gear has been required to have narrowband (2.5kHz max deviation) capability since around 1997 or 1998, IIRC. Some ham gear started offering the capability shortly after that. My Icom IC-T90A small HT just narrows the deviation when in narrow mode but doesn't narrow the receiver. A lot of newer ham gear also narrows the receiver too.

My Yaesu FT-60 handheld also narrows the receiver when in narrow mode. My Yaesu FTM-10R mobile rig also narrows the receiver in narrow mode. It seems a lot of the specs and capabilities of the good commercial gear eventually trickles down to the ham gear.
 

BonziBuddy

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Commercial gear has been required to have narrowband (2.5kHz max deviation) capability since around 1997 or 1998, IIRC. Some ham gear started offering the capability shortly after that. My Icom IC-T90A small HT just narrows the deviation when in narrow mode but doesn't narrow the receiver. A lot of newer ham gear also narrows the receiver too.

My Yaesu FT-60 handheld also narrows the receiver when in narrow mode. My Yaesu FTM-10R mobile rig also narrows the receiver in narrow mode. It seems a lot of the specs and capabilities of the good commercial gear eventually trickles down to the ham gear.
I have a FT-60 and it's basically my fire scanner more than my Minitor pager. How do you make it narrow? I've tried and the smallest deviation it has is 5kHz

My county will be switching over soon (thankfully not encrypted) and I want to get ready right now so I can help out the other guys and buffs in my department.
 

zz0468

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Commercial gear has been required to have narrowband (2.5kHz max deviation) capability since around 1997 or 1998, IIRC. Some ham gear started offering the capability shortly after that. My Icom IC-T90A small HT just narrows the deviation when in narrow mode but doesn't narrow the receiver. A lot of newer ham gear also narrows the receiver too.

Yep. I've been aware of the commercial requirements for years, but since I don't pay too much attention to amateur FM equipment, I haven't been aware that narrow band amateur radios are available, especially since there's no requirement or incentive for amateurs to go narrowband.

A radio that narrows deviation, but not the receiver IF doesn't do the OP any good, since his requirements are for public safety RX only.

My Yaesu FT-60 handheld also narrows the receiver when in narrow mode. My Yaesu FTM-10R mobile rig also narrows the receiver in narrow mode. It seems a lot of the specs and capabilities of the good commercial gear eventually trickles down to the ham gear.

It does make me wonder just what the manufacturers have in mind, or how firmly grounded in reality they are. Any widespread deployment of 2.5 KHz amateur systems (other than 900) is years away, if it happens at all. I presume your Yaesu radios have wide coverage RX?
 
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DaveNF2G

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The Yaesu VX-7 (and I presume the VX-8) has a 7.5 kHz channel spacing option. Unfortunately, it is only accurate within the upper 2 meter band. The Part 90 VHF band has several start and stop points for channelization and the VX-7 is not programmed to follow the additional bandplans.
 

n1das

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I have a FT-60 and it's basically my fire scanner more than my Minitor pager. How do you make it narrow? I've tried and the smallest deviation it has is 5kHz

Main Menu--->WIDNARR-->(select WIDE or NARROW)

Go into the main menu and give the knob a twirl to scroll through the list and dial up WIDNARR on the display. The main menu items are arranged alphabetically. The two available options to select under WIDNARR are WIDE and NARROW.

If you're listening to a signal while changing the setting, you'll definitely hear the change it makes on the received audio. If you tune 5 kHz or 10 kHz off-frequency from the signal, you can hear the effects of wide vs. narrow mode on the received signal. It appears to tighten up the receiver in narrow mode.

The wide/narrow setting (menu item WIDNARR) works in VFO and is stored in memories, so you can set it per memory too. If you recalled a memory and changed the the wide/narrow setting that was previously stored in memory, you'll need to write it to memory again to store the change.

Good luck.
 
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cquirk

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Narrow

We have 1 repeater in the SF Bay area that is 2.5 deviation. The big problem we have is when new operators come on the channel they are unaware of the setting and they cut in and out of the repeater. We tell them to turn their microphone around and talk into the back of the microphone to reduce the modulation
 

zz0468

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We have 1 repeater in the SF Bay area that is 2.5 deviation. The big problem we have is when new operators come on the channel they are unaware of the setting and they cut in and out of the repeater. We tell them to turn their microphone around and talk into the back of the microphone to reduce the modulation

What band is the repeater on? If it's not on 900, why is it narrowband?
 

stevelton

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Because there are ham groups our there that want to build repeater systems that are similar to public safety conventional repeater systems.

Same reason I am building a 2 meter repeater that will run mix mode analog/ Icom IDAS, and on the analog side will use DCS code.

Also, one of te same reasons Chicago's Fishfar has a wide area repeater system, but you have to use commercial equipment to use it, (i.e. Be able to transmit a MDC1200 code)

Steven
 

zz0468

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Because there are ham groups our there that want to build repeater systems that are similar to public safety conventional repeater systems.

Ok... Fair enough. it would be interesting to see how much of a headache it presents with a preponderance of potential users being unequipped to run narrow deviation, and many unequipped to even understand the requirement. Running DCS might be enough to solve the problem. And maybe the problem will solve itself when the preponderance of unequipped users get fed up with the low talk back audio.
 

W2NJS

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Wideband vs. narrowband, etc.

zz0468 wrote...

"...and many unequipped to even understand the requirement."

I would think, and I certainly hope it's true, that anyone holding an FCC license at the Technician level or above would have absolutely no problem understanding the basics of wide vs. narrow these days. Of course, I also realize, for example, that one heck of a lot of hams still don't understand PL and DPL, so maybe my expectations are too high and we have more applicance operators than actual technicians in our ranks.
 

zz0468

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I would think, and I certainly hope it's true, that anyone holding an FCC license at the Technician level or above would have absolutely no problem understanding the basics of wide vs. narrow these days.

It's nice to hope but the reality is, many new Technician level hams know just enough to answer the 35 question test. That's ok, but it's up to the more experienced people to get them up to speed.

Of course, I also realize, for example, that one heck of a lot of hams still don't understand PL and DPL, so maybe my expectations are too high and we have more applicance operators than actual technicians in our ranks.

Listen to the 2 meter band, and read the questions that get posed here, and on other radio forums. It's clear that there's a lot of people who's technical background only goes as far as an interest in radio, and a 35 question test.

That's fine, and not an indictment against anyone. Everyone has to start somewhere. But it does illustrate why I think running NFM in a band that is predominantly using WFM is going to cause some confusion. I'm not opposed to doing it, just cognizant of the possibility that some people won't "get it".
 

E5911

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im looking for a dual band mobile that will do true narrow band receive. Also has a remote head option.

Any sugesstions?
 

AK9R

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I know that the Kenwood TM-V71 and TM-D710 have narrow band FM. The head on the TM-V71 can be remoted while the head on the TM-D710 is remote mount by default.
 
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