Modulation NFM?

[BillyFive]

Greetings.

When my local SO switched to Tach Red, I hear nothing. I notice this channel is labeled NFM as opposed to FM. I have tried everything in my (limited) knowledge; (Analogue, Digital, Both) to no avail. Anyone? Uniden BCD436HP.

 

[doctordialtone]

Greetings.

When my local SO switched to Tach Red, I hear nothing. I notice this channel is labeled NFM as opposed to FM. I have tried everything in my (limited) knowledge; (Analogue, Digital, Both) to no avail. Anyone? Uniden BCD436HP.

Perhaps that channel is encrypted. Post a link to the channel from the database?

 

[nd5y]

Maybe if you provided more information like the system, city and state somebody could help you.

 

[mmckenna]

Greetings.

When my local SO switched to Tach Red, I hear nothing. I notice this channel is labeled NFM as opposed to FM. I have tried everything in my (limited) knowledge; (Analogue, Digital, Both) to no avail. Anyone? Uniden BCD436HP.

Narrow FM is 2.5KHz deviation analog. FM is 5KHz deviation analog. Your Scanner would be able to hear narrow FM just fine if it was set to FM or NFM, although the signal may sound distorted or quiet.

Don't trust the database 100%, it is info submitted by volunteers, so you get what you pay for….

Sometimes (as in not always) Tac channels can be simplex. If they are running simplex and are not really close to you, it's possible that you just may not hear them.

Or, as others said, could be encrypted. Some agencies like to encrypt tac channels.

Either way, no one can help you if we don't know where you are.

 

[BillyFive]

Perhaps that channel is encrypted. Post a link to the channel from the database?

Not sure how to do that because it's on Sentinel. So I took a screen shot.

 

[doctordialtone]

This:

Either way, no one can help you if we don't know where you are.

 

[belvdr]

Not sure how to do that because it's on Sentinel. So I took a screen shot.

What system is this? There’s data in the RR database that isn’t shown in Sentinel.

 

[KevinC]

Based on previous posts and some sleuthing of the listed frequencies I believe this is in Santa Cruz, California so I moved it. Either way it's not a RR database question.

 

[mmckenna]

If you were listening to Santa Cruz County Sheriff on their SO Blue channel, and they said they were switching to Red, then you have your frequency programmed correctly. If you are hearing Blue, you should also be able to hear Red as it's repeated from the same radio sites. SCC SO is still running analog Narrow FM.

Be aware that in the near future they have plans to move all their channels to P25 with full time encryption. I'd expect that to happen in the next year or so.

 

[BillyFive]

Maybe if you provided more information like the system, city and state somebody could help you.

Narrow FM is 2.5KHz deviation analog. FM is 5KHz deviation analog. Your Scanner would be able to hear narrow FM just fine if it was set to FM or NFM, although the signal may sound distorted or quiet.

Don't trust the database 100%, it is info submitted by volunteers, so you get what you pay for….

Sometimes (as in not always) Tac channels can be simplex. If they are running simplex and are not really close to you, it's possible that you just may not hear them.

Or, as others said, could be encrypted. Some agencies like to encrypt tac channels.

Either way, no one can help you if we don't know where you are.

Maybe if you provided more information like the system, city and state somebody could help you.

What system is this? There’s data in the RR database that isn’t shown in Sentinel.

Santa Cruz CA County Sheriff, Blue also shows NFM and is fine, Red Tac goes silent when they switch

 

[KevinC]

Check your Service Types and see if Interop is turned on.

 

[mmckenna]

Santa Cruz CA County Sheriff, Blue also shows NFM and is fine, Red Tac goes silent when they switch

All of their stuff is NFM. That was mandated by the FCC on Jan 01, 2013.

Red is a countywide interoperability channel and all local law enforcement agencies have access to it. The programming is common across the board, repeater coverage pretty much countywide, all linked.
It's possible they are using it in simplex, but I've never heard them do that, and I've never seen radios programmed to use it simplex.

I agree with KevinC, make sure your scanner is set up correctly.

 

[BillyFive]

Check your Service Types and see if Interop is turned on.

Thank you very much. Just checked and it is set to Interop. I changed the modulation from NFM to Auto to see if that makes a difference. Won't know until they use it again.

 

[BillyFive]

All of their stuff is NFM. That was mandated by the FCC on Jan 01, 2013.

Red is a countywide interoperability channel and all local law enforcement agencies have access to it. The programming is common across the board, repeater coverage pretty much countywide, all linked.
It's possible they are using it in simplex, but I've never heard them do that, and I've never seen radios programmed to use it simplex.

I agree with KevinC, make sure your scanner is set up correctly.

Thank you both very much. Just checked and it is set to Interop. I changed the modulation from NFM to Auto to see if that makes a difference. Won't know until they use it again.

 

[KevinC]

Thank you very much. Just checked and it is set to Interop. I changed the modulation from NFM to Auto to see if that makes a difference. Won't know until they use it again.

I highly doubt changing from/to NFM will make any difference, but I could be wrong.

I believe @mmckenna is near your location so he probably knows what he's talking about as far as usage goes. Anyway, good luck.