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Locate the connector housing (backshell) and associated hardware.
Note:
A single hinged backshell may be provided rather than a two-
piece backshell.
Attach a backshell to the male connector at the KAT100 end of
the cable. Figure 18 shows how the backshell appears when assembled.
Use the provided cable clamp to hold the cable in position, then secure
the clamp with two screws. The jackscrews must be retained by the
shells. Secure the backshell halves with the provided hardware (or, if
the shell is hinged, snap the backshell closed).
BACK SHELL
CLAMP
JACK SCREW
Figure 18
Attach a backshell to the connector at the K2 end. If you have
not built an RS232 cable, you should have an unused backshell from the
KIO2 or KPA100 kit. If you did build an RS232 cable, re-install the
backshell you removed earlier. The hole in the backshell should
accommodate both 4-conductor cables.
Power Cable Assembly
The KAT100 requires a source of 10-15 V DC. A mating plug is
supplied for the KAT100's power jack, J1. You can make a separate
cable for the KAT100, or build a "Y" cable to share power with the K2
or K2/100.
If your power supply does not have a fuse, you may wish to add a
1-amp fuse of any type in-line with the KAT100's DC input.
K2 Control Board, R12
If your K2 is s/n 2999 or lower, you'll need to install a resistor in series
with the VRFDET line on the K2 Control board as described below.
This will protect the K2's microcontroller from accidental damage if
you have a short in the KAT100 control cable. (K2s s/n 3000-up
already have this resistor, designated R12.)
Remove the two screws that hold the K2 control board to the
front panel. Also remove the KAF2 if present. Remove the control
board using the long-handled Allen wrench (supplied with the K2).
Locate the trace on the top side of the K2 Control board that
runs between resistors R8 and R9 (see drawing below). Cut the trace.
On the bottom of the board, solder an 820-ohm resistor (gray-
red-brown) between the two vias. You'll need to pre-trim the resistor's
leads since it isn't possible to cut the lead that falls between R8 and R9.
R8 R9
Cut
R12 (on back)
K2 Control Board, C44
Remove the Control board, if necessary (see above).
C44 (0.1 µF) on the K2 Control board, if present, must be
removed (it causes inaccuracy in current measurement). On the
revision B Control board, C44 is located near microcontroller U1. On
earlier Control boards, C44 is not on the board, but in lieu of this you
may have soldered a capacitor directly across R7. Remove it in either
case.