Mostly the cable is a pass through. The KAT500 has a relay to interrupt the amp key line during ATU tuning, and the KAT500 can observe (but not change) the exciter-controlled band lines.
The ATU needs the frequency. The amp needs the band. Both amp and ATU have TX freq counters. Both amp and ATU have publicly documented mechanisms to be controlled by external automation to return to freq-appropriate settings before transmission. We provide automation from K3, K3S, and K4 when you use the optional 15-pin ACC cables and select the appropriate settings in exciter, amp, and ATU. These are convenient, but not the only way the amp and ATU can be used. If the amp were able to set band lines for the ATU, it would be of marginal utility. The ATU could return to the last used setting on that band. As soon as you QSY, the ATU would probably need to move, based on the tx freq count. 73 de Dick, K6KR > On Nov 18, 2020, at 10:18, [email protected] wrote: > > So what does the HD15 cable do from the KAT500 to the KPA500? I thought > that the KAT controlled the amp but perhaps it is just passing the K3 data > through. > > John KK9A > > > > Jack Brindle W6FB wrote: > > I received a bit of further information this morning. The KAT500 only uses > the band data to validate that the received frequency (from the K3) is on the > indicated band. It does not use it for anything else. > > Further, the KPA500 only uses band data to select the band. In general, the > KPA doesn’t care about the frequency - it really has no frequency-sensitive > elements. The KPA does not receive frequency from the K3, and only uses the > Kenwood data (or Icom band voltage) to select a band. Thus there is no data > to be sent. > > I believe you are searching for a solution that gathers transceiver frequency > and sends it to the KAT500. Or, allow the KAT500 to use its built-in > frequency measurement system to select the bin. > > Jack, W6FB > > >> On Nov 18, 2020, at 8:00 AM, Wes <wes_n7ws at triconet.org> wrote: >> >> Thanks Andy. >> >> I'm starting to get my head around this. "Tis a pity that Elecraft didn't >> allow for the KPA500 to control the KAT500 via the band data bus and have an >> integrated Amp/Tuner combo that didn't require a proprietary interface. >> >> The tuning solutions are in the tuner memory so telling it, or letting it >> measure, the frequency recalls them. >> >> Wes > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]

