I have been using the Elecraft KPA-500 and KAT-500 with two Icom rigs; the IC-7600 and the IC-7300. This article details how I have chosen to interconnect the KAT/KPA-500 with my IC-7300. There are many options for interconnecting the 7300 with this Elecraft “power combo.” There also many opinions on the various wiring approaches. A couple of the main issues that I have seen discussed include:
- Tuning power provided by the IC-7300 – Elecraft suggests that the Tuner behaves best when it gets at least 20 Watts of RF power from the Transmitter. That would suggest that the use of the TUNE button on the 7300 may not be the best approach. I have found that this works quite well. I have also seen some test data that shows that there is little difference in the Tuner’s behavior when getting 10 Watts or 20 Watts.
- Need for BAND Data being sent to the KPA-500 – The Elecraft design makes it very easy to interface with any Radio. It is possible to use just the RF into the Tuner to get the Tuner and Amp configured properly. I prefer to send the BAND data from the 7300 to the KPA-500 amplifier. I just feel better knowing that the Amp knows what is coming, when I key up the Transmitter.
The following diagram shows my overkill approach for connecting the IC-7300 to the KPA/KAT-500. This allows me to use the 7300 TUNE button or the TUNE button on the Elecraft KAT-500 Tuner Utility when I want to Tune to a frequency.
Details for each of the cables are provided below
Monitoring the Setup While Operating
Elecraft provides two very nice software Utilities for monitoring and configuring the KAT-500 and the KPA-500. I always keep these open on my PC desktop when operating. It allows me to hit the TUNE button, change configurations, or monitor Power and SWR without looking at the front panels of the equipment. Below is a screenshot of each of the utilities:
If you look closely at the KAT-500 App screenshot, it looks like my SWR is off-the-charts. No, I am not using an antenna with a 15:1 SWR. I took this screenshot in the morning following a 160m contest, after changing my antenna (outside the shack) to a ZS6BKW. You can see from the KPA-500 screenshot that the Rig is still on 160 meters. This shows how easily I can see if something strange is happening on my antenna system. In the situation above, it would not be possible to KEY the KPA-500, as the KAT-500 will not allow it due to the apparent excessive SWR. If I hit the TUNE button, the Amp will not be keyed and will probably be forced into STANDBY mode. So I could not possibly transmit into my ZS6BKW while tuned for 160m.