Service manual

Guide to ASTRO™ Digital Radios
There are two versions of the ASTRO Digital Saber™: Versions manufactured prior to November
1996—which contain a 512K vocon board and models manufactured post-November 1996, which
contain a 1-meg vocon board. What’s the difference?
512K vocons utilize three flash ROMs—two 256K flash ROMs (512K) for storage of the host
firmware, and one 256K flash ROM for storage of the DSP firmware.
1-meg vocons utilize a 1MB flash ROM to store the host firmware and one 256K ROM to store
the DSP firmware.
Figure 2.2 ASTRO Digital Saber™ vocon boards. Photo “A” shows a 1-meg vocon. Photo “B” is a 512K version. ASTRO Digital Spectra™ vocons are
identical in appearance and layout, however a different connector is present and some components are missing. Note the distinguishing 1-meg
flash ROM (U205) in photo “A”.
How do you know which version (vocon size) you have? Maybe you’re looking at an eBay
auction or a table of “teh astors” at Dayton. Some ASTRO Digital Sabers™ have a distinct 1-meg sticker
on the back—but you can’t always rely on this indicator. Some radios are parts-built (more on this later)
or perhaps someone has swapped a 512K vocon in place of the original 1-meg vocon. The serial number
can help one determine the vocon size, if the radio is original or a second-hand surplus unit from a
federal government or police auction. Here is an example of a Motorola Inc. serial number which could
represent an ASTRO Digital Saber™: