PRI-COMMS on PCsat de WB4APR ------------------ --------- On 24 Jan we initiated a new phase of experimentation by turning on the special store-and-forward Priority Communications feature of the PCsat mission. This experiment can capture Emergency and Priority messages from the THD7 and D700 anywhere on the planet and hold them for retransmission over the USA on 144.39. Remote travelers desiring access to this experiment may apply for access... This feature is based on some slight modifications to the HEARD log built into the PCsat KPC-9612 TNC. Instead of capturing all calls heard, the PRI-COMMS feature uses a new AHEARD list of only those calls that have indicated Emergency or Priority status. And not just their calls, but their entire packet is captured. Thus the AHEARD log can capture emeregency or priority packets from anyone anywhere even in the remotest corner of the earth. To downlink these packets, PCsat's KPC-9612 TNC' have a new command called ABEACON. The ABEACON command determines how often and how many of the stations in the log are to be transmitted in the down link. ALthough this was a quick and dirty method to extend PCsats communi- cations ability to remote corners of the Earth where no other HAM ground station is in range, it is not very efficient. Just turning on the ABEACON for say the last 2 packets once every 5 minutes, results in over 500 packets being transmitted arond the world for the next 24 hours or longer. Thus The PRI-COMM feature of PCsat normally is disabled except when someone needs it. In that case, we ask that all remote travelers register their travel plans with the PCsat command station well in advance of travel showing what dates they want PRI-COMM access. ALso due to a last minute addition of this feature to the PCsat flight ROMS, it was only added to the B side. SO users will also need access to the unpublished B side uplink.. PCsat is designed for the speific purpose of remote travelers. We hope they will use it when they get an opportunity. de WB4APR, Bob