Service manual

Guide to ASTRO™ Digital Radios
The W4 control-head can also be modified to disable the ignition-sense. JU1 and JU2 must be
installed.
Figure 5.8 blown-up schematic illustration of 0-ohm chip resistors JU1 and JU2 which must be installed on the Motorola ASTRO Digital Spectra™
W4 control-head if the ignition-sense circuit is to be disabled.
The ASTRO Digital Spectra™ is available in low-power (15W) motorcycle versions, mid-power 40-
50W versions and 110W remote/trunk-mount high-power versions. Command boards, control-heads
and vocon boards found in these various models are all compatible with each other, provided you have
the right interconnect board and cabling. (Refer to service manual for part numbers.) Additionally, you
must install a new codeplug/s-record with Lab-tool RSS when swapping heads. More on these
procedures is discussed later in the guide.
Encryption hardware modules used in the ASTRO Digital Spectra™ are 100% compatible with
those found in ASTRO Digital Sabers™. As stated earlier in the guide, the vocons for both radios (The
encryption module attaches to the vocon) are nearly identical, with the exception of different interface
connectors. There are firmware-specific details to be aware of for compatibility. More about the
encryption capabilities of Motorola Inc. ASTRO™ products is discussed later in the guide.