Re: Icom 7300, KAT500 and KPA500
Bill Mader <billamader@...>
The KAT500, unlike the AH-4, can follow band/frequency information from the radio. Once "trained" on antenna tuning solution by frequency for each antenna port, the KAT500 switches to the last port used on that frequency and provides the "trained" solution (see the manual). Unfortunately, while the KPA500 follows the band data the IC-7300 provides (assuming you have used the appropriate interface cable), the KAT500 cannot follow that band data. The KAT500 has to wait for RF before switching to the correct antenna port and tuning solution.
Since you must use RF sensing in the KAT500, you must provide a brief burst of RF to cause the KAT500 to switch to the proper port and tuning solution. This will cause the KPA500 to fault if the KAT500 is not on the proper port and tuning solution for that frequency, even when running the KEY/PTT line through the KAT500. BTW, using the Manual operation once "trained" is the preferred method of operating the KAT500.
Perhaps there is a software solution to this problem? It is theoretically possible to command the KAT500 to switch appropriately from a computer. The software could provide the next channel's frequency, pass it to the radio (to the KPA500 from the IC-7300) and KAT500, and both would be prepared for the RF. Running ALE is not the "normal" amateur radio experience and thus requires a well thought out integrated solution.
When powered up, the KAT500 is in-line with the last used antenna port and tuning solution for that frequency. The IC-7300 cannot supply frequency information to make the KAT500 follow it. This would seem to be an opportunity for someone to offer an interface box that could read Icom CI-V frequency information and convert it to the format the KAT500/KPA500 can read and thus act upon it.
The AH-4 cannot accomplish this plus it can't handle 500 Watts. The KPA1500 with its internal tuner can read Icom CI-V frequency data and take the appropriate actions (one of two antenna ports and last solution for the chosen frequency). I am not suggesting you purchase a KPA1500, just letting you know this "magic" is possible.
73, Bill Mader, K8TE
K-Line, KX3, KX1, K2
W6H NM Coordinator, Route 66 On-the-Air 4-13 Sep 2020
Duke City Hamfest BoD Vice-Chairman www.dukecityhamfest.org 18-20 Sep 2020
Secretary and Past President, Albuquerque DX Association