13
Important ATU Operating Tips
• A 1.0:1 SWR is
not
necessary for good performance. See
Antenna Considerations
.
If the final SWR is above 3:1, you may want to use lower power or re-configure
your antenna. (The impedance matching range is reduced on 80 meters.)
• If you switch between the various ATU modes frequently, you can assign the
A T U
menu entry
to the programmable function switch,
P F n
(see the K1 Owner's Manual for details).
• If you use
D I S P L A Y
to put the K1 into supply voltage display mode, then enter TUNE, you'll
see the transmit-mode battery voltage, not SWR or power output. The ATU settings will not change.
• The ATU menu entry can be used to display the current values of L, C, network type, and other data.
See
ATU Modes
for a full listing of all status displays.
ATU Modes
Table 1
lists all of the KAT1’s operating modes, and what is displayed when TUNE is activated in each
mode. The ATU’s
T U N
mode is used for normal operation. In this and all other modes where SWR is
displayed, power is dropped to approximately 1.5 watts during TUNE. You can override this level by
setting power
lower
using the
O U T
menu entry. However, if you see
P
L O
on the LCD during TUNE, you
may have power set too low to obtain a stable SWR reading.
The other modes are primarily used for calibration and troubleshooting:
•
In
C L S
mode (as well as
C L P
), the L and C relays are all reset (L and C = zero).
•
The
L 0
-
L 4
,
C 0
-
C 5
,
N 1
, and
N 2
modes select individual L/C/net relays for test purposes.
Note: In modes
L 0
-
L 4
, capacitance is set to 0. In modes
C 0
-
C 5
, the inductance is set to about 1 µH.
See Troubleshooting for details on how to make use of these modes.
•
The
F x . x
menu entry shows the firmware revision. If you enter TUNE in this mode you should
see
r 8 . 5
, which is a test pattern for the digital SWR data sent over the RFDET/DATA line.
Table 1. ATU Modes
Mode
Description
T U N E
Mode
Description
T U N E
CLP
Used for calibration of R1;
L/C =
0
Power
NTx
1=Cin, 2=Cout (present band)
SWR
CLS
SWR bridge only;
L/C = 0
SWR
Exx
1-49 = error (see Troubleshooting)
SWR
TUN
Auto-tune mode
SWR
Fx.x
KAT1 firmware revision, e.g. F1.0
r 8 . 5
OUT
Forward power display
Power
L0-L4
Individual inductor test (C = 0)
SWR
rx.x
SWR from most recent TUNE
SWR
C0-C5
Individual capacitor test (L = 1 µH)
SWR
Lx.x
Inductance, µH (present band)
SWR
N1
Network relay test, Cin (L/C = 0)
SWR
Cxx
Capacitance, pF x10 (present band)
SWR
N2
Network relay test, Cout (L/C = 0)
SWR
