Users Going To Narrower Bandwidth Equipment

The General forum is where users can discuss any topic regarding Motorola communications equipment - hardware, software, etc. There are also several focused forums on this board, so please take the time to ensure that your questions doesn't fall into one of those categories before posting here!

Moderator: Queue Moderator

Post Reply
Jim1348
Posts: 542
Joined: Sun Aug 15, 2004 7:52 am

Users Going To Narrower Bandwidth Equipment

Post by Jim1348 »

I am starting to notice that some radio users near me who are remaining analog, but upgrading to newer compliant equipment, going from PL to DPL. Are you folks starting to notice that also in other areas of the country?
User avatar
Bill_G
Posts: 3087
Joined: Thu Sep 17, 2009 5:00 am

Re: Users Going To Narrower Bandwidth Equipment

Post by Bill_G »

It's a coin toss. Those with a tight budget are staying analog, and only replacing the radios needed. Those with some extra money are upgrading to Trbo for the added features.
KG4INW
Posts: 285
Joined: Thu May 22, 2008 3:31 pm
What radios do you own?: Not enough apparently!

Re: Users Going To Narrower Bandwidth Equipment

Post by KG4INW »

I haven't noticed that around here. What would be the reason, you think for switching from PL to DPL? I can't think of any reason and why they initially chose one over the other, seems to be whatever the programmer felt like doing that day.
trumpetman12
Posts: 71
Joined: Fri Aug 06, 2010 6:10 pm

Re: Users Going To Narrower Bandwidth Equipment

Post by trumpetman12 »

I've noticed that going on here as well, mainly switching the tones on the input. My assumption is to make sure those with personal radios are making an effort to get them reprogrammed and switched to narrowband, otherwise the radios won't work anymore (at least on trasmit).
User avatar
Tom in D.C.
Posts: 3859
Joined: Tue Sep 04, 2001 4:00 pm
What radios do you own?: Progreso soup can with CRT

Re: Users Going To Narrower Bandwidth Equipment

Post by Tom in D.C. »

I believe that much depends on how much effort (meaning sophistication) the agency's service shop, be it in-house or an outside contractor, puts into their work. The sharp ones know to use different PLs on the inputs and outputs of the repeaters to keep outsiders from kerchunking or otherwise interfering with the systems' operations. I have noted a slight swing to greater use of DPL as I scan the RR database, but that might be just me. Using DPL rather than CTCSS (PL) could be a result of a poor coordination effort when the licenses were obtained, something I used to experience when I was buying coordinated licenses some years ago.
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
GlennD
Posts: 482
Joined: Tue Jun 15, 2004 8:00 am

Re: Users Going To Narrower Bandwidth Equipment

Post by GlennD »

In our case we switched to DPL to insure the non-compliant radios like the Sabers stuck in the locker as a spare are not usable. There would be lots of radios that are left wideband that would be just in case radios.
User avatar
Bill_G
Posts: 3087
Joined: Thu Sep 17, 2009 5:00 am

Re: Users Going To Narrower Bandwidth Equipment

Post by Bill_G »

I misread the OP. That makes no sense. Our customers rarely care whether their system is PL or DPL. We are definitely not seeing customers requesting NB and a PL/DPL change. The closest we got to that was a national school bus company with a confusing mix of radio models in some yards. It was fubar mess.

We are up to our eyeballs in system upgrades to Trbo however. 60 hour weeks is the norm right now trying to keep up.
thebigphish
Posts: 1477
Joined: Sat Nov 29, 2003 10:10 pm
What radios do you own?: AM/FM

Re: Users Going To Narrower Bandwidth Equipment

Post by thebigphish »

"digitull is bettur"

DPL > PL

Someone sold someone on that logic!
"How do you plan to outwit Death?"
"With a knight and bishop combination; I will destroy his flank.
" --Antonious Block
k2hz
Posts: 531
Joined: Tue Mar 01, 2005 7:27 am

Re: Users Going To Narrower Bandwidth Equipment

Post by k2hz »

I think there is a perception that DPL has some advantages over PL such as more available codes and possibly better
performance at the lower deviation levels.

Switching from PL to DPL in the past was not always an easy option since some older radios could not do DPL. With the change to all NB compliant radios, DPL was a standard feature. If it was just a case of blocking non-compliant radios all that needed to be done was to change the existing PL.
KB2ZTX
was jsikora
Posts: 269
Joined: Wed Jun 11, 2003 9:38 am

Re: Users Going To Narrower Bandwidth Equipment

Post by KB2ZTX »

In reading this thread I must admit some of this makes sense. I didn't think about changing a PL/DPL on our infastructure but have been seriuosly wondering how to get all the radios that are users of the system reprogrammed to the new requirements. Maybe switching the PL/DPL is a easy way to get this done as users will not be able to access the repeaters without the reprogram. In the volunteer SAR world i livei n many member buy there own radios and it took us 20 years just to get everyone on a common PL tone...switching to 12.5 Khz spacing is going to be even harder.
KB2ZTX
User avatar
Bill_G
Posts: 3087
Joined: Thu Sep 17, 2009 5:00 am

Re: Users Going To Narrower Bandwidth Equipment

Post by Bill_G »

jsikora wrote:In reading this thread I must admit some of this makes sense. I didn't think about changing a PL/DPL on our infastructure but have been seriuosly wondering how to get all the radios that are users of the system reprogrammed to the new requirements. Maybe switching the PL/DPL is a easy way to get this done as users will not be able to access the repeaters without the reprogram. In the volunteer SAR world i livei n many member buy there own radios and it took us 20 years just to get everyone on a common PL tone...switching to 12.5 Khz spacing is going to be even harder.
Ok. Now that makes sense. If you are a system owner, and you want to ensure compliance, or you want an accurate count of the number of users, changing the access PL would force them to get their radios programmed. However, if you are not in total control of radio maintenance, you will not see every radio in a conventional system. Other shops, or their "friends", will see some portion of the radios.
User avatar
tdats
Posts: 172
Joined: Tue Jun 10, 2008 8:23 am
What radios do you own?: Mostly Motorola

Re: Users Going To Narrower Bandwidth Equipment

Post by tdats »

We took the narrow-banding reprogramming opportunity to change the input PL on our repeaters to help with interference issues we have been fighting. We scanned our input for a while counting PL hits until we found a couple that we where not receiving. We stuck with an analog PL though, but I suppose we could of went to a DPL. I wounder if other repeater operators are doing something similar. Changing the PL to make sure every radio gets re-programmed though is not a bad idea. I have heard a few though that sound like they are still wideband around here, but have our new PL, so it is not foolproof.
KB2ZTX
was jsikora
Posts: 269
Joined: Wed Jun 11, 2003 9:38 am

Re: Users Going To Narrower Bandwidth Equipment

Post by KB2ZTX »

Correct Bill, but at least I will hear from each person that needs this completed when they are looking for the PL/DPL code that I change it to. With the amount of work any radio tech has going on right now in regards to the deadline I am fine with people going other places to get reprogrammed. Although this wouldnt solve 100% of the issues Im sure it would bring 95% of the radios into complience. The larger issue is getting folks to spend funds on a new radio when we tell them the old one cannot be used.
KB2ZTX
resqroz
New User
Posts: 19
Joined: Mon Jan 28, 2008 5:49 am

Re: Users Going To Narrower Bandwidth Equipment

Post by resqroz »

I just changed one of our systems to narrowband. I chose a different PL to make sure that I would catch all of the radios that needed to be changed when they didn't work on the new system. I chose DPL because we had a few places in our building where computer noise would false the pl opening.
Jim202
Posts: 3610
Joined: Sun Sep 09, 2001 4:00 pm

Re: Users Going To Narrower Bandwidth Equipment

Post by Jim202 »

One big negative that I know of going to a digital code is that you can shut it all off by using a PL of 136.5. It turns off all the digital coded receivers that might be listening to a signal.

Use to do that with a taxi outfit on the same business frequency as I had a number of years ago. Every time I keyed up my base, it would kill anything they might be listening to unless they had a stronger signal than mine. They would never shut up and just kept jabbering about nothing just to keep the channel tied up.

Jim
motorola_otaku
Posts: 1854
Joined: Tue Jan 13, 2004 7:03 am

Re: Users Going To Narrower Bandwidth Equipment

Post by motorola_otaku »

In the instances I've noticed, it was done to mitigate long-standing issues with skip interference. This has been primarily among VHF-highband licenses.
Post Reply

Return to “General Motorola Solutions & Legacy Radio Discussion”