900 MHz XTS1500

[Kd9dxf]

Hi: I have a XTS1500 for 900MHz amateur radio use. I've got the Astro25 software, V20.xx with the hex mods done for the amateur radio bands. However, it won't let me set any of the channels to wideband 25 kHz, only 12.5. It shows them on the pull down, but with the "eyeglass" read only pointer, and won't let you select it. Is there another mod to the software to allow 25kHz? Per the specs on the XTS, it can do either on 900. But there is a restriction in the Astro25 software. I looked at the help and it talks about having the FCC narrowband restriction.
Or, am I missing something like the 33cm/900MHz band is narrowband only? Some of my fellow hams in the area are operating wideband, with Motorola radios, but don't know what software they used for programming.
Thank you, '73 John - KD9DXF

 

[KJ4DHF]

Sounds like your XTS is flashed with Q507 12.5 kHz FCC Mandate in the flash code.

 

[GTR8000]

Set the Tx Option Transmit Dev to 2.5 kHz; the other fields are read-only.

 

[N4KVE]

Or, am I missing something like the 33cm/900MHz band is narrowband only?

This is my understanding. Since the 935-941 commercial band is narrow band only, & Motorola only builds commercial radios, narrow band is the only choice. Possibly someone figured out a hex edit for wide band?

 

[K9KLC]

Hi: I have a XTS1500 for 900MHz amateur radio use. I've got the Astro25 software, V20.xx with the hex mods done for the amateur radio bands. However, it won't let me set any of the channels to wideband 25 kHz, only 12.5. It shows them on the pull down, but with the "eyeglass" read only pointer, and won't let you select it. Is there another mod to the software to allow 25kHz? Per the specs on the XTS, it can do either on 900. But there is a restriction in the Astro25 software. I looked at the help and it talks about having the FCC narrowband restriction.
Or, am I missing something like the 33cm/900MHz band is narrowband only? Some of my fellow hams in the area are operating wideband, with Motorola radios, but don't know what software they used for programming.
Thank you, '73 John - KD9DXF

Are they using the exact same radios? We can do wide band on the XPR stuff, it seems so I'm not sure what's up there.

 

[GTR8000]

Set the Tx Option Transmit Dev to 2.5 kHz; the other fields are read-only.

I'm an idiot. First of all, that should've been "Set it to 5.0 kHz" if you want to change to wideband. Also I just checked ASTRO CPS with a 900 MHz XTS 1500 codeplug, and even without Q507 in the FLASHcode, it still won't allow you to change 33cm ham frequencies to wideband Tx deviation.

 

[hill]

Or, am I missing something like the 33cm/900MHz band is narrowband only? Some of my fellow hams in the area are operating wideband, with Motorola radios, but don't know what software they used for programming.

Must be rare, as most hams just run narrow band on 33 CM. This is what most radios are set to and think some of Kenwood radios used on 33 CM only do narrow band on it.

 

[Kd9dxf]

Thank you for your information. Going down the google rabbit hole, the FCC narrowband mandate, from what I read, required any radio made after Jan 1, 2011 be narrowband only? From the rules,

"VHF and UHF transmitters that operate with a maximum channel bandwidth greater than 12.5 kHz may not be manufactured in or imported into the United States after January 1, 2011 unless the efficiency standard is satisfied".

Decoding the serial number on my radio, says it was manufactured in Aug 2011.

Could this be it? The model number says it's a Version B radio (Model # H66WCD9PW5BN) but the 9th digit (9) decodes to a programmable channel spacing.

Any ideas? I read the code plug when I got the radio, and it was all narrowband. I wonder if it's "inheriting" the 12.5-only from that codeplug? Could one get a plug from another XTS that has 25 in it and use that, or brick the radio?

I've just used the Astro25 programming software. Wondering if there is a restriction somewhere in the software?

Again, MANY THANKS
John, KD9DXF

 

[GTR8000]

900 MHz had nothing to do with the narrowbanding mandate, which only affected certain subsets of the VHF high and UHF bands, as is made clear in what you quoted.

The issue seems to be that MSI never allowed wideband 2.5/25.0 kHz programming in the 900 MHz spectrum, regardless of whether Q507 was in the FLASHcode or not. It has nothing to do with the codeplug.

There may be a way to hex edit the codeplug and/or ASTRO25 CPS to allow wideband operation. I'll let others speak to that.

 

[mikewazowski]

I've never known the 900MHz commercial band to be anything other than narrow band. Motorola used to offer "HearClear" as an attempt to make the audio a bit better sounding.

 

[otobmark]

On 900, the difference between FM and P25 is night and day. I found 900 FM to be nearly useless because of noise and no signal punch. P25 and suddenly it works. Check the N6LXX network in CA who have a lot of experience with 900mhz amateur, including simulcast. I would not use 900 analog and in fact gave away my 900 analog radios long ago. I have no idea what availability of 900mhz quantars or equivalent are but they would not be expensive. My current objection to 900 is lack of new P25 radios except maybe Tait or is it BK? I have a XTS2500 with hex edited cps and it works fine.

 

[N4KVE]

For the last 2 years 900 APX 4000’s have been doing 902/927 ham freq’s. FPP too. And yes, 900 P25 is far superior to 900 analog. There’s even some 900 DMR repeaters around.