VHF NARROW BAND RADIOS
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stueyneumann
- Posts: 16
- Joined: Tue Feb 24, 2004 2:33 am
VHF NARROW BAND RADIOS
IN THE NEXT YEAR OR SO WE HAVE TO ADD NEW MABAS FIREGROUD FREQS FROM 25 TO 12.5 PER OUR MEMBERSHIP RULES. THE QUESTION I HAVE IS DOES ANYONE HAVE A LIST OR KNOW OFF HAND WICH OF THE OLDER PROGRAMMABLE RADIOS CAN GO TO THE NARROW BAND FOR PROGRAMMING. E.G. HT1000, MT1000, HT600, GP300, GP350, MAXTRAC, GM300
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Aces-Warehouse
- Posts: 168
- Joined: Fri Jan 23, 2004 10:27 pm
While 12.5 X 2 = 25 / It still doesnt meet the ruling as to deviation and bandwidth permited .
Yes you can program a freq in at 12.5 steps and tx on it as well but your still 25 khz wide at that programed freq.
The true 12.5 radios would tx at 12.5 bandwidth and not as wide as the 25 khz which would eliminate txing into the next 12.5 freq that the FCC is trying to get up and running in the future.
The GP300 was made in 12.5 freq models ( You could not program it from 25 to 12.5 in the program) It was one or the other from the factory.
The Maxtrac was available in 12.5 as well from the factory.
The model number tells you the bandwidth of the radio and most of the time in the model number the 25khz radio had 20 in the model number where the 12.5khz radio had 00 in it.
The P1225 and M1225 were 12.5 or 25 bandwidth selectable by the rss program and was able to do eigther one or both.
Motorola does make a conversion kit that converts the GP300 or the Maxtrac from 25 to 12.5 if youd rather use your radios still and they are these models.
Id qeuss M probably has other kits for other radios as well = youd have to check on that to see.
The major diferences of the 25 versus 12.5 radios was that the 25 radios IF was a crystal with a big tolerance that allowed it to tx at a 25 bandwidth and 12.5 radios IF was much tighter in tolerances that kept the freq at a 12.5 width.
If you look at my profile and then select find all posts by me = you will run across a post i made awhile back as to what it took for components
and the part numbers for the kits and Motorolas price and even a info on what and how its done ect.
Lets all have a good day.
EKLB
Yes you can program a freq in at 12.5 steps and tx on it as well but your still 25 khz wide at that programed freq.
The true 12.5 radios would tx at 12.5 bandwidth and not as wide as the 25 khz which would eliminate txing into the next 12.5 freq that the FCC is trying to get up and running in the future.
The GP300 was made in 12.5 freq models ( You could not program it from 25 to 12.5 in the program) It was one or the other from the factory.
The Maxtrac was available in 12.5 as well from the factory.
The model number tells you the bandwidth of the radio and most of the time in the model number the 25khz radio had 20 in the model number where the 12.5khz radio had 00 in it.
The P1225 and M1225 were 12.5 or 25 bandwidth selectable by the rss program and was able to do eigther one or both.
Motorola does make a conversion kit that converts the GP300 or the Maxtrac from 25 to 12.5 if youd rather use your radios still and they are these models.
Id qeuss M probably has other kits for other radios as well = youd have to check on that to see.
The major diferences of the 25 versus 12.5 radios was that the 25 radios IF was a crystal with a big tolerance that allowed it to tx at a 25 bandwidth and 12.5 radios IF was much tighter in tolerances that kept the freq at a 12.5 width.
If you look at my profile and then select find all posts by me = you will run across a post i made awhile back as to what it took for components
and the part numbers for the kits and Motorolas price and even a info on what and how its done ect.
Lets all have a good day.
EKLB
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phonegunner
- Posts: 65
- Joined: Tue Jun 24, 2003 8:57 am
Just a heads up on the webb site on narrow band compiant radios.
Checking further and also taking into consideration the disclaimer at the bottom of this same webb sites information.
At the bottom of the Motorola page for compliant and non compliant radios it states info was gathered from many sources and may not be complete.
I do see the GP300 listed as non compliant and this would be true of the 25 khz model but does not apply to the 12.5 model that contains the 00 numbers in its model number id.
Also a 25 radio converted with 12.5 conversion kits available frm Motorola
become 12.5 compliant due to the proper conversion of said radio.
If you look closer at some of the other radios that it says are 12.5 or 25 khz capable depending on its model from the factory youll notice they still state non compliant but thats pertaining to the 25 khz model from the factory rather than the 12.5 as im told.
The list is even incomplete to a degree when you look at the GP300 as it did not mention 12.5 or 25 eigther one but are aparently refering to the 25 radio with the 20 number in the model number.
And another that confuses me is the Motorola M10 listed as 25 or 12.5 available but lists it as non compliant at 25 khz band but compiant at 12.5khz and im reasonably certain the 25 khz model will not meet 12.5 crteria = but would if its a 12.5 model.
So im not convinced the list is complete or updated = but thats me.
But the list is rather interesting and brings up a few qestions for me as well now that ive seen it.
EKLB
Checking further and also taking into consideration the disclaimer at the bottom of this same webb sites information.
At the bottom of the Motorola page for compliant and non compliant radios it states info was gathered from many sources and may not be complete.
I do see the GP300 listed as non compliant and this would be true of the 25 khz model but does not apply to the 12.5 model that contains the 00 numbers in its model number id.
Also a 25 radio converted with 12.5 conversion kits available frm Motorola
become 12.5 compliant due to the proper conversion of said radio.
If you look closer at some of the other radios that it says are 12.5 or 25 khz capable depending on its model from the factory youll notice they still state non compliant but thats pertaining to the 25 khz model from the factory rather than the 12.5 as im told.
The list is even incomplete to a degree when you look at the GP300 as it did not mention 12.5 or 25 eigther one but are aparently refering to the 25 radio with the 20 number in the model number.
And another that confuses me is the Motorola M10 listed as 25 or 12.5 available but lists it as non compliant at 25 khz band but compiant at 12.5khz and im reasonably certain the 25 khz model will not meet 12.5 crteria = but would if its a 12.5 model.
So im not convinced the list is complete or updated = but thats me.
But the list is rather interesting and brings up a few qestions for me as well now that ive seen it.
EKLB
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RADIOMAN2002
- Posts: 1102
- Joined: Thu Apr 04, 2002 4:00 pm
- What radios do you own?: More than I can count
The Web Site posted has a slightly different set of rules than reqular commercial radio regulated by the FCC. CAP and other Federal agencies use NTIA for coordination and enforcement. Most CAP radios sundown within the next 2 years while business will run for another 7 to 8.
I have been doing some conversions of Maxtracs to narrow band. I am using components from 900mhz maxtracs, for audio compandering and I am about to try and use the IF section. If you do not live in a very crowded RF enviroment, you could just turn the PL and TX audio down to 2.5kc deviation., and live with the low RX audio or add the Compander board from some old 900 radios, readily availible, at most flea markets or E-bay.
This whole mess just shows how the FCC and the Manufacturers got together and decided it was easier to outlaw the old radios,(so they can sell new ones) they should have taken the same tact as 30 years or so ago when they first lowered TX deviation. Have kits made availible to upgrade the radios.
I have been doing some conversions of Maxtracs to narrow band. I am using components from 900mhz maxtracs, for audio compandering and I am about to try and use the IF section. If you do not live in a very crowded RF enviroment, you could just turn the PL and TX audio down to 2.5kc deviation., and live with the low RX audio or add the Compander board from some old 900 radios, readily availible, at most flea markets or E-bay.
This whole mess just shows how the FCC and the Manufacturers got together and decided it was easier to outlaw the old radios,(so they can sell new ones) they should have taken the same tact as 30 years or so ago when they first lowered TX deviation. Have kits made availible to upgrade the radios.
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phonegunner
- Posts: 65
- Joined: Tue Jun 24, 2003 8:57 am
The major problem that comes up is that under CAP the radios will need to be compliant for both Narrow and Wide (and for funding purposes for newly acquired P25 compliant) to work with those in the infrastructure that will be either Narrow or Wide (IE: Marine channel 16 will end up staying Wide) when the sunset occurs.
The other is that unless the manufacturer deems that the modification to the radio is compliant CAP will not accept the compliancy. Of course this does not hurt CAPs funding side but the member owned equipment investment side.
The other is that unless the manufacturer deems that the modification to the radio is compliant CAP will not accept the compliancy. Of course this does not hurt CAPs funding side but the member owned equipment investment side.
Veni, Vidi, Vici.....TOGA!!!
In fact the "A", "B", "C" and "D" models are all 12.5 compatable."D" model HT1000s will do narrow band on a per channel basis and work quite well.
The later models (C and D versions) have higher spec 2 PPM reference oscilators and the "D" model can be programmed to new "Splinter" channels.
I have found that the A, B, and C all require a complete alignment for proper narrowband operation.
Also avoid 141.3 Hz PL (+/- 10Hz). there is a strange artifact if you have a HT1000 programmed to narrowband, have a PL around 141 Hz and are running carrier squelch. Sounds like a swarm of bumble bees. Same issue as the HT1250, but they have baseband offset to correct the issue.
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Big Blue TO/\/\
- Batboard $upporter
- Posts: 213
- Joined: Fri Aug 30, 2002 12:16 pm
Getting a headache here, I know it's a dumb question, but some radios appear Narrowband COMPLIANT and yet NOT P25 Capable.
My questions
Difference?
Regulations, ie: I have radios that ARE narrow compliant but not P25, so will those radios have to be replaced?
Beginning to work on funding, etc. , and been up all night.
Tom
My questions
Difference?
Regulations, ie: I have radios that ARE narrow compliant but not P25, so will those radios have to be replaced?
Beginning to work on funding, etc. , and been up all night.
Tom
KE4RXM
You don't drink beer? Use Motorola RSS, you WILL soon...
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Tom in D.C.
- Posts: 3859
- Joined: Tue Sep 04, 2001 4:00 pm
- What radios do you own?: Progreso soup can with CRT
compliance...
Further to Matt's answer, narrowband FM is modulated FM, whereas P25 is entirely different and is digital data which requires decoding. Wideband FM the same almost as narrowband, but the transmitted audio makes a wider swing and the received audio is put through a much wider bandpass on the receiver.
Narrowband uses about half the spectrum space of wide, which is why it's eventually being required for all commercial and govt. users.
Narrowband uses about half the spectrum space of wide, which is why it's eventually being required for all commercial and govt. users.
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
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.
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phonegunner
- Posts: 65
- Joined: Tue Jun 24, 2003 8:57 am
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Big Blue TO/\/\
- Batboard $upporter
- Posts: 213
- Joined: Fri Aug 30, 2002 12:16 pm
"And in 2018 we are supposed to be at 6.5 KHZ even narrower"
I read tonight on an Aviation related angle (their new radios will be called Nexcom) that the Brits have tried 8.33 and per the article, that's the NARROWEST current technology can support.
Any takers on whether the 6.5 will actually happen?
Thanks, Tom. I understand the band-width part, but was getting cornfused 'bout the whole P25 thing, and how it applied to (or if it did) to bandwidth. I think I have it now...
Basically unless the radio is capable of digital modes, no P25 . I don't know yet whether we will have to be P25 compliant or now, with the "new" system... the state wants to do what many others do, have a "statewide" radio system but that's still a few years away. their literature indicates what I believe will be P25 functions, but who knows what will be there once they actually throw the switch (based on available $$ )
I read tonight on an Aviation related angle (their new radios will be called Nexcom) that the Brits have tried 8.33 and per the article, that's the NARROWEST current technology can support.
Any takers on whether the 6.5 will actually happen?
Thanks, Tom. I understand the band-width part, but was getting cornfused 'bout the whole P25 thing, and how it applied to (or if it did) to bandwidth. I think I have it now...
Basically unless the radio is capable of digital modes, no P25 . I don't know yet whether we will have to be P25 compliant or now, with the "new" system... the state wants to do what many others do, have a "statewide" radio system but that's still a few years away. their literature indicates what I believe will be P25 functions, but who knows what will be there once they actually throw the switch (based on available $$ )
KE4RXM
You don't drink beer? Use Motorola RSS, you WILL soon...
PLEASE use EMAIL over PM. Much Easier for Me. Thanx!
You don't drink beer? Use Motorola RSS, you WILL soon...
PLEASE use EMAIL over PM. Much Easier for Me. Thanx!
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wb4bsd
- Batboard $upporter
- Posts: 254
- Joined: Fri Mar 14, 2003 10:07 am
- What radios do you own?: XTS5000v, MTS2000v, MTS2000u
Heres my question about Narrow Band. Why, and i am sure this answer will be over my head, will my MTS2000 not go secure when my TX deviation is set to 2.5Khz vice 5Khz? So for those agencies that use secure voice, when the transition is made to narrow band, we or they will no longer be able to go secure.
thanks
thanks
Rusty
(I no longer have nextel. I now have an iPhone)
(I no longer have nextel. I now have an iPhone)
Narrowband Secure
Hi,
The current DVP, DES and the -XL variants are all 25 kHz bandwidth modes - they won't work on a 12.5 kHz narrow channel. The radio is smart enuff not to let you try!
There are newer encryption modes that will function at 12.5 kHz (2.5 kHz deviation), but the older ones won't.
73 DE Hartley
The current DVP, DES and the -XL variants are all 25 kHz bandwidth modes - they won't work on a 12.5 kHz narrow channel. The radio is smart enuff not to let you try!
There are newer encryption modes that will function at 12.5 kHz (2.5 kHz deviation), but the older ones won't.
73 DE Hartley