Astro Saber III VHF - Narrow Band and DSP Questions

[AL7OC]

Will a VHF Astro Saber III with the latest ROS (R07.71.06) do 2.5 kHz channel spacing (tuning increments?) In addition to ham channels, I need to program the radio for some of our Part 90 channels that are on the new narrow band assignments. For example, 154.5275, 155.9125, 156.1375...

How does "I" version DSP firmware differ from "N"? The DSP firmware in the unit in question is I08.XX.XX. After reading r0f's Guide to Astro Radios, it appears that this firmware supports with P25 IMBE. The notes also state that the "I" prefix is paired with "M". No clue what that means. My other Astro has "N" version DSP and it works fine with P25. Anyone know how "I" DSP differs from "N" DSP?

Thanks for any help with these questions.

-Pierre

[Tom in D.C.]

I tried putting one of your .5275 channels into a 5.02 CPS program and it took it fine and nothing came up red in the View screen as a trouble point. Didn't try actually loading it into the radio, however. Why don't you try it yourself on one channel and see what a frequency counter reports when you transmit?

[jmr061]

Yes the astro saber with that new of host/dsp will support 2.5khz channel spacing and narrowband. As far as the end user is concerned there is no difference between I or N dsp. I have been led to believe I dsp are early board versions and N are later manufacture runs.

Jason

[AL7OC]

Thanks for the information on DSP versions and 2.5 kHz channel spacing. I don't have a Astro Saber yet, but I am considering getting one for my collection. My CPS for the XTS3000 will program 2.5kHz channels, but I don't have an Astro Saber to try it on. (Same CPS) It looks like if I get one, it'll work out fine.

-Pierre