I went back and reviewed the KAT500 command set and it doesn't look like this is possible because the serial protocol does not have a way to communicate split status. I've been knee deep in the KPA500 serial protocol (with great results thanks to Jack W6FB) and thought they may have some high level similarities, but not really.
Do you know how the KAT500 interprets frequency, if driving only the band data lines (BAND0-3) via an external TTL device? Does it pick middle of the band if there is no last used frequency? 73, Cliff K3LL -----Original Message----- From: Cliff Frescura [mailto:c...@cfcorp.com] Sent: Sunday, November 15, 2015 2:58 PM To: 'Cady, Fred'; 'Elecraft@mailman.qth.net' Subject: RE: [Elecraft] KAT500 Re-Tuning Apparently yes. However, I'm using the KAT500 serial port to communicate frequency to the KAT500 via logging software (DXLabs), not auxBus, since the radio is not a K3/S. 73, Cliff K3LL -----Original Message----- From: Cady, Fred [mailto:fc...@montana.edu] Sent: Sunday, November 15, 2015 2:28 PM To: Cliff Frescura; Elecraft@mailman.qth.net Subject: Re: [Elecraft] KAT500 Re-Tuning Are you asking for the KAT500 to choose two different tuning solutions when operating split? At present it chooses the VFO B frequency for its solution according to: MCU 4.83 / DSP 2.82, 2-8-2014 * FSK-D (RTTY) POWER-CONTROL BUG FIX: Power output can now be increased while in transmit mode when using FSK-D. * KAT500 ATU SUPPORT: Automatic retuning of KAT500 LC network as K3 VFO is moved. VFO frequency messages are sent via the auxBus. Sends VFO A frequency except in SPLIT mode, where VFO B frequency is sent. Cheers, Fred KE7X www.ke7x.com for all KE7X Elecraft books. ________________________________________ From: Elecraft <elecraft-boun...@mailman.qth.net> on behalf of Cliff Frescura <c...@cfcorp.com> Sent: Sunday, November 15, 2015 3:09 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KAT500 Re-Tuning Antenna issues specific to the OP aside, there is a valid reason to have the KAT500 recognize split and inhibit retuning/recall. The need for this functionality is very apparent when running split on 40m SSB when the DX is below 7.1 MHz and listening up much higher than 5KHz for anyone using a narrow bandwidth 40m antenna. Consider that the KAT500 already tuned the antenna on your TX, so the "fix the antenna solution" doesn't apply. Listening ~50KHz away should not require any retuning since the tuner's settings at your TX should be good enough for RX. Here is how it would work: 1. When the KAT500 sees a *transition* from split off to split on... a. The KAT500 would recall settings for TX Frequency or retune (under the VSWR settings condition) when it sees RF for the first time after this split transition 2. When split is on (Split mode) b. The tuner should not change any settings regardless of frequency/band - except under VSWR conditions based on settings. c. Perhaps both the "Auto" and "Man" indicators would be on in order to indicate this mode on the KAT front panel. 3. When the KAT500 sees a transition from split on to split off then go into "normal" (non Split) mode. The main reason I am using the tuner is because of a compromise antenna. If the antenna was flat enough across the band I wouldn't even engage it. In my specific situation there is also at KPA500 connected, so the way that the KAT500 works today will result in the KAT inhibiting the KPA while it retunes/recalls. Although fast, I suspect that the amp is not engaged initially when I send (speak) my call sign in the pile. On very rare occasions there is also a KPA VSWR Fault. While probably not an issue, the amount of relay chatter in very short period of time between fast RX/TX/RX transitions is a bit unsettling. 73, Cliff K3LL -----Original Message----- From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Jim Brown Sent: Sunday, November 15, 2015 10:04 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KAT500 Re-Tuning On Sat,11/14/2015 8:37 PM, Byron Peebles wrote: > I will put the antenna analyzer on it tomorrow and make sure it's > still solid after all this wind. Other suggestions. First, put it on bypass and see what the SWR indication is. If it's reasonable, go to MAN mode, force a tuning (put K3 in TUN mode) and let it tune. Carefully check the entire coax path between K3 and the antenna. All connectors should be finger tight, then tighten with gas pliers. Any indication that the coax is wet? Moisture entering anywhere along the run will usually migrate all the way down to the lowest point. Open connectors to see if there's any moisture. A good way to test is to use a tissue or paper towel as a probe. If you have TDR capability, look at the feedline for any discontinuities. You should see connectors, the antenna, and any switching between the antenna and your test point. Most vector analyzers can do TDR. If you don't have one of them, ask around your ham neighbors to borrow one (and ask them to help you do the measurement). 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to c...@cfcorp.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to fc...@montana.edu ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com