GA All,
Around last December, I posed the question on how does the KAT500 actually works. This is the answer I received from Dick at Elecraft, the person who designed the software for the KAT500. Most likely he probably wrote it too. There was, however, a request from Eric, Elecraft CEO, when the info was sent to me and I had wanted to know if it was ok for me to pass this info around. Hi Jerry, Eric, our CEO says >>> Sure. But note that Dick does not have time available to answer questions on this as he is tied up on other work. << Thanks for asking in advance. 73, Doug So please do not ask Dick anymore about this subject. As you will see, Dick went into great detail on how the KAT500 works From: Dick Date: Fri, Dec 13, 2019 at 1:40 AM Subject: RE: Question about the KAT500 capability. To: Elecraft Support <[email protected] <mailto:[email protected]> > Here is how the KAT500 storage allocation works. EEPROM storage for ATU settings is pre-allocated by frequency. I’ve called “the storage area for the six ATU settings for a given frequency segment” a “bin” because the word is often used in the program and documentation. Each “bin” has room for 6 ATU settings. Each of these 6 ATU settings contains bits for the ATU relays (L, C, side, ATU bypass and ANT relays) plus an SWR measured when the ATU was bypassed. The antenna number (ANT relay bit settings) is included in the ATU setting, so we don’t need to preallocate something like 2 ATU settings for ANT1 and 2 ATU settings for ANT2 and 2 ATU settings for ANT3 in a 6-setting bin. Thus you can have 5 ATU settings for ANT 1 in the bin for 1801-1810 and one ATU setting for ANT2 in the same bin. The next bin for 1811 thru 1820 might have 3 settings for ANT2 and 2 settings for ANT3 and one empty. The most recently used ATU setting is moved to the front of the bin when you tune to that setting. When you have a “full” bin, all 6 entries have ATU settings, and do another tune, it might push out the oldest setting. No duplicate settings are stored in any given bin. There is bin storage pre-allocated for all frequencies between 1.501 and 60 MHz. We have MARS, CAP, and a few other commercial/military customers. We didn’t know ahead of time what the frequencies would be for all these customers. MARS customers aren’t always allowed to tell us the exact frequencies they use. So we allocated storage assuming a continuous range between 1.5 and 60 MHz. The ATU isn’t a transmitter, we aren’t constrained to the ham bands. For 80 meters the “bin width” is 20 kHz. Bin 1 is 3001 thru 3020 kHz Bin 2 is 3021 thru 3040 Bin 3 is 3041 thru 3060, etc. The 80 meter ham band is 500 kHz wide (3500-4000). At 20 kHz per bin, there are 25 “bins” for the 80 meter ham band. 3481-3500 one bin, 6 ATU settings. 3501-3520 one bin, 6 ATU settings 3521-3540 one bin, 6 ATU settings. The ATU overall from 1.5 to 60 MHz has room for 1530 “bins” each containing up to 6 ATU settings. That’s just over 12,000 ATU settings. But most of these are outside the ham bands. Here’s an excerpt from a planning spreadsheet: Our “160 meter band” goes from 1501 through 3000 kHz, 80 meters goes from 3001 through 4800, etc. The frequencies ranges and band names match the K3. Band Name Ham Band Start Ham Band End Ham Band Width Lower Limit Upper Limit Band Width Bin Width Bin Count 160 1800 2000 200 1501 3000 1500 10 150 80 3500 4000 500 3001 4800 1800 20 90 60 5330 5405 75 4801 6000 1200 20 60 40 7000 7300 300 6001 9000 3000 20 150 30 10100 10150 50 9001 13000 4000 20 200 20 14000 14350 350 13001 17000 4000 20 200 17 18068 18168 100 17001 19000 2000 20 100 15 21000 21450 450 19001 23000 4000 20 200 12 24890 24990 100 23001 26000 3000 20 150 10 28000 29700 1700 26001 38000 12000 100 120 6 50000 54000 4000 38001 60000 22000 200 110 73 My de Dick, K6KR Best regards, Jerry, W1IE ______________________________________________________________ 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]
