[Elecraft] [KAT500] Auto Tuning

[Fred Jensen]

I actually have a KAT500.  Using the KAT500 Utility, I set up the 
antennas [I have 3, a very convenient number] so that the preferred 
antenna is automatically selected and if one won't ever be used on that 
band, I de-selected it.  All that works fine.

The memory segments vary by band, doing this from my wetware memory 
[always chancy], 160=10KHz, 80-12=20KHz, 10=100KHz, and 6=200KHz.  The 
manual puts it a bit differently ... "below 3 MHz," "between 3 and 
[something]," can't remember and too tired to look it up, and so forth. 
  So, I really didn't know where the center of the segments are.

I assumed they began at the bottom of the ham bands, so for 160 I 
started at 1805 and worked up in 10KHz increments.  I do not know this 
is right, it's complicated by my antennas.  The tri-bander is really 
stable, although it is slowly falling apart, I find trap parts on the 
ground under it, but the KAT500 gets a 1:1 anywhere on 3 bands with one 
click.  The WARC vertical is not as stable, I think it waves in the wind 
a little, but it's OK too.

The low band wire [235' sloping Vee] is fed with ladder line to a 4:1 
DXE "balun" [please, let's not start that thread again, you all know 
what I'm talking about :-)] is unstable in rain, snow, and fog, and the 
KAT500 memorized settings need to be retuned in real-time.  That's *my* 
problem, not the tuner's.

In AUTO or MAN, tuning consists of:

1.  Tapping the TUNE button on the KAT500

2.  Holding the XMIT button on the K3 [doesn't matter what mode I'm in] 
so it goes into Tune mode -- TUN PWR needs to be 20-25W.

3.  Letting it tune

4.  Tapping the XMIT button

Doesn't matter if the KPA500 is in OPER or STBY, it doesn't key while 
the KAT500 is tuning.  Mileage with other amps may vary.  I've tried the 
"Fine Tune" thing by tapping TUNE [KAT500] right after it finishes, 
sometimes it may find a better match, generally not, and it's usually 
not worth the time on my particular antennas.  Mileage may vary with 
different antennas.

I don't run AUTO on 80 and 160 because it seems to want to retune by 
itself if I QSY much and this happens while I'm sending [or speaking in 
the rare times I find myself on phone].  MAN mode seems to suppress that.

I've tried just holding XMIT and seeing if it wants to tune and then 
tapping it again.  I think it works, results have been confusing to me 
however [a fairly common occurrence as I accumulate birthday candles], 
and I generally just do the above since I'm in control of that process.

The manual might have spelled out the center frequencies of the "tuning 
segments" on each band a bit more clearly, but basically, I bought it, I 
built it, I did what the manual said, I played with it and got familiar 
with it, and I'm a happy ham.  I can think of many things that "might be 
good and make it better," that's also the reason I never really 
"finished," in my mind, any software I've ever written.  I just quit 
because the customer was happy, accepted it, and paid us.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2013 Cal QSO Party 5-6 Oct 2013
- www.cqp.org

On 1/27/2013 7:22 PM, Ron D'Eau Claire wrote:

> If you really want to avoid being surprised by a tune operation commencing
> when you go to a new frequency, step through the bands at the intervals
> listed in the manual (or at least do this on your favorite
> bands/frequencies) to "teach" the KAT500 what the proper L/C/Ant settings
> are for each frequency. Then it will almost instantly return there next time
> you transmit.