Astro Spectra Plus
The Astro Spectra Plus is a variant of the Astro Spectra with an upgraded vocon to allow it to run on Astro25 firmware and be programmed by the Astro25 CPS.
Hardware
RS232 Programming
The ASP can be programmed using a straight-through RS232 serial connection using either the rear DB15 on mid-power units or the front DB25 on high power units. The pinouts for the cable using a standard female DB9 connector on the computer side are shown below.
| Signal | Computer DB9 | Mid-Power DB15 | High-Power DB25 |
| RXD | 2 | 11 | 2 |
| TXD | 3 | 13 | 3 |
| CTS | 8 | 1 | 17 |
| RTS | 7 | 15 | 4 |
| GND | 5 | 8 | 18 |
Additionally, some jumpers may need to be moved as some ASP units were shipped without RS232 functionality on the ports. The detailed service manual gives a chart for non-RS232 jumper placement, and reversing these jumpers will re-enable RS232 operation.
Software
Available Flashcode Options
Out of Band
See Astro Spectra#Out of Band for information as the Plus shares the same VCO hardware.
P25 Out of Band Limitations
Unfortunately for those wishing to use P25 in the ham bands, there is a firmware restriction for the UHF-R and VHF-K bandsplit radios which prevents the vocon from modulating P25 below 450 and 148 MHz, respectively. This firmware limitation can be worked around by directly editing the codeplug partition, but unfortunately this requires tools even more advanced than standard Astro25 Depot.
