Motorola Spectra Introductory Information


Posted on Feb 6, 2014

No matter WHAT the label on the radio (or the seller) says, no Spectra will ever operate over the entire 136-174MHz (high band) or 403-512MHz (UHF) frequency range. Each unit will do only a portion of that band`s frequency spread, and that portion is called a `split`, a `bandsplit` or a `range`. You can stretch things a little and go a megahertz or maybe two


Motorola Spectra Introductory Information
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out of range and that`s about it. If you buy the wrong range radio for your application (for example a 403-433MHz and you want to use it on 440-450MHz amateur frequencies, or a 482-512MHz radio for GMRS) it just won`t work and you will have a nice doorstop. Despite what you see on eBay there is not (and never was) a 406-440MHz range. And it is not practical to range-change a Spectra radio. For more information scroll down to the section titled "Splits/ Ranges". Another note: Spectras are wideband only (+/- 5 KHz except on 900 MHz). Yes, the 900MHz band has been 2. 5KHz (narrowband) since the beginning. You probably could hack and slash at a Spectra and make it to where it would work in a narrowband environment, but it would be narrow only, not switchable. Plus it would not be type accepted and would not be legal. If you need a narrowband radio and want to stick with the Spectra line then you will have to find an AstroSpectra. The Spectra line was MD`d (Manufacture Discontinued) a few years ago, and depot maintenance was terminated recently. Many public safety agencies nationwide are being forced into new radios (if they stay with Motorola it`s usually the MCS2000 series) and the Spectras are showing up in surplus in large quantities. Due to the fact that the "narrowband" units are what is considered today as wideband they will be illegal to use in commercial and public safety use when the narrownand rules go into effect....




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