ELECRAFT K3 User manual

ELECRAFT K3
HIGH-PERFORMANCE 160 – 6 METER
TRANSCEIVER
KIO3B INTERFACE OPTION
INSTALLATION INSTRUCTIONS
Revision A2, February 5, 2016
E740280
Copyright © 2016, Elecraft, Inc.
All Rights Reserved

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Contents
Introduction ............................................................................................................................................... 3
Preparing for Installation .......................................................................................................................... 3
Check K3 Firmware Version............................................................................................................................... 3
Anti Static Protection Required ........................................................................................................................... 3
Tools Required .................................................................................................................................................... 4
Parts Included ...................................................................................................................................................... 4
Installation Procedure ............................................................................................................................... 5
Removing the Top Cover .................................................................................................................................... 5
Initial Setup ............................................................................................................................................. 12
Computer Interface ................................................................................................................................. 12
USB Computer Interface ................................................................................................................................... 12
Forcing a Firmware Download Using the USB Interface ............................................................................. 13
RS232 Computer Interface ................................................................................................................................ 13
P3 Panadapter Interface .......................................................................................................................... 13
Monitoring RS232 Data .......................................................................................................................... 13
Customer Service and Support ............................................................................................................... 15
Technical Assistance ..................................................................................................................................... 15
Repair / Alignment Service ........................................................................................................................... 15
Appendix A – K144XV Cabling ............................................................................................................ 16
Elecraft manuals with color images may be downloaded from
www.elecraft.com.

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Introduction
The KIO3B upgrade kit (KIO3BUPKT) consists of three pc board modules, the KIO3 main board, the audio
board and the digital board. The audio and digital boards plug into the main board. All audio and digital input
and output signals are routed through the KIO3B.
A USB port is provided for a single-cable solution for most PC interface needs including control and line-level
audio input and output. The KIO3B module also digitizes audio routed to the USB port, eliminating the need for
a computer sound card and associated cables. RTS or DTR signals for PTT and KEY inputs are available at the
USB and RS232 port to support logging or control programs using these signals for controlling transmit/receive
switching or CW keying.
The RJ45 connector provides an RS232 interface and communicates with the Elecraft P3 Panadapter.
The DE15 accessory connector provided on the original KIO3 is included for external band decoders (such as
the Elecraft KRC2), transverters such as the Elecraft XV series and similar devices. The accessory connector is
also used for direct FSK or PSK signaling.
The audio board provides the same three analog interfaces as the original: stereo headphone, stereo speaker and
a transformer isolated line output. It also has monaural microphone and isolated line inputs. Bias for an electret
microphone can be provided at the microphone input using the K3 menu. The analog inputs and outputs are
available even when the USB interface is being used.
Preparing for Installation
Check K3 Firmware Version
The KIO3BUPKT requires firmware level 5.26 or above be installed in your K3:
 Connect your K3 to power and tap POWER to turn it on.
 Hold CONFIG. The firmware version will be displayed on the LCD.
 If needed update your firmware as described in your K3 Owner’s manual.
Anti Static Protection Required
We strongly recommend you take the following anti-static precautions (listed in order of importance) to avoid
ESD (Electro Static Discharge) damage:
 Leave ESD-sensitive parts in their anti-static packaging until you install them. Parts which are
especially ESD-sensitive are identified in the parts list and in the assembly procedures.
 Wear a conductive wrist strap with a series 1-megohm resistor. If you do not have a wrist strap, touch a
bare metal ground briefly before touching any sensitive parts to discharge your body. Do this frequently
while you are working. You can collect a destructive static charge on your body just sitting at the work
bench.
WARNING
DO NOT attach a ground directly to yourself without a current-limiting
resistor as this poses a serious shock hazard. A wrist strap must include a
1-megohm resistor to limit the current flow. If you choose to touch an
unpainted, metal ground to discharge yourself, do it only when you are not
touching any live circuits with your other hand or any part of your body.
 Use a grounded anti-static mat on your work bench.
 No soldering is required but if you choose to use a soldering iron for any reason, be sure your iron has
an ESD-safe grounded tip tied to the same common ground used by your mat or wrist strap.

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Tools Required
1. #0 and #1 size Phillips screwdrivers. To avoid damaging screws and nuts, a power screwdriver is not
recommended. Use the screwdriver that best fits the screw in each step.
2. Wrench to remove jack screw nuts on the K3 back panel. A 3/16” nut driver is recommended.
3. Small needle-nose pliers or tweezers to position small parts.
4. Soft cloth or clean, soft static dissipating pad to lay cabinet panels on to avoid scratching.
Parts Included
The following parts should be included in your kit. Check to ensure you have them all. If any parts are damaged
or missing, contact Elecraft for replacements (see Customer Service and Support, page 15).
ILLUSTRATION DESCRIPTION QTY. ELECRAFT
PART NO.
KIO3B Main Board
ESD Sensitive. 1 E850645
Digital I/O Board
ESD Sensitive. 1 E850646
Audio I/O Board
ESD Sensitive. 1 E850647
KIO3B Digital I/O Panel 1 E100558SS
Jackscrew Nut, 4-40
Note: The jackscrew nuts may be
mounted on the DB-15 connector on the
KIO3B Digital I/O Board.
2 E700078
Continued on next page

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Screw, 4-40, 1/4” (6.4 mm) Black, Pan
Head 2 E700174
Lock Washer #4 Split 2 E700004
RJ-45 to DE-9S 1 E980297
USB A-B Cable 1 E850720
Installation Procedure
Removing the Top Cover
Disconnect power and all cables from your K3.
Remove the nine screws to free the top cover as shown in Figure 1. After the cover is open, lift it gently to
reach the speaker wire connector. Unplug the speaker. If the K144XV is installed, slip the connector under the
stiffener at the depression in the cover of the K144XV module (see Figure 12 on page 11). Set the top cover
aside in a safe place.
Whenever you remove screws from a panel, if one screw seems too tight to loosen
without damaging it, first loosen the other screws then try again. Sometimes one screw
binds in its hole when the other screws are tightened.
Figure 1. Removing K3 Top Cover.

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CAUTION: Touch an unpainted metal ground or wear a grounded wrist strap
before touching components or circuit boards inside the K3. See Anti Static Protection
Required on page 3 for more information.
If you have the K144XV module installed, disconnect the power and TMP cables from the K144XV
module.
CAUTION: The TMP connectors are friction fit and pull straight out. Do not pull on
the coax cables or you may pull a cable out of its connector. Use your needle-nose pliers to
grasp the metal part of the connector visible outside of the K144XV enclosure and pull it
straight out.
Remove the seven screws shown in Figure 2 to free the panel and lift the panel off of the K3. Note that
Screw 1 is not the screw through the side panel, but is the screw through the lip at the top of the rear panel. This
will free the 2D fastener inside to come off with the side panel, which will make removing the existing KIO3
board easier, especially if you have the KRX3 sub receiver installed. If the K144XV 2-meter option is installed
carefully shift the panel as needed for the K144XV module to clear the chassis stiffener bar.
Figure 2. Removing the K3 Left Side Panel.
Remove the rear panel cover over the KIO3 (see Figure 3)
Figure 3. Removing the KIO3 Rear Panel Cover.

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Unplug the digital I/O board from the KIO3 main board (see Figure 4). Set the digital I/O board aside. We
recommend that you store the boards in the ESD-safe envelopes the new boards came in as you replace them.
Figure 4. Removing the Remote I/O Board.
Remove the KIO3 board upper standoff (see Figure 4). Take care not to lose the screw or lock washer
inside the K3. You can temporarily stand the K3 on the open side so if you drop the hardware it will fall onto
your bench and not inside the K3.
With the K3 on its bottom feet, unplug and remove the KIO3 board (see Figure 5). Rock it while lifting it
upward as necessary to “walk” the connectors at the K3 RF board apart.
Figure 5. Removing the KIO3 Board.

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Remove the standoff from the original KIO3 board and mount it on the KIO3B main board as shown in
Figure 6.
Mount the new audio I/O board on the main board as shown in Figure 6. Be sure you don’t mix up the new
and old audio I/O boards. The new board has part number E850647 near one corner and the connector pins.
(Another part number is shown between the multi-pin connector and the jacks. Look for the correct number near
one corner of the board.)
Figure 6. Mounting the Standoff and Audio I/O Board on the KIO3B Main Board.
Plug the KIO3B main board into the J76 on the K3 RF board (the same connector used by the original
KIO3 board, see Figure 5). Be sure all the pins engage the connector.
Mount the upper standoff you removed from the original KIO3 board in the same location on the KIO3B
main board, using the original screw and lock washer (see Figure 4).
Plug the new digital I/O board into the remaining connector on the KIO3B main board as shown in
Figure 7. Be sure all the pins engage and the connectors are fully seated.
Figure 7. Installing the KIO3 Digital I/O Board.

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Mount the new digital I/O panel as shown in Figure 8. Do not tighten the screws or jack screw nuts until
they have all been started on their threads and the connectors are aligned in the panel cutouts.
Do not over-tighten the jack screw nuts. Too much torque can twist the hex head off of
the threaded shaft.
Figure 8. Mounting the new KIO3B Rear Panel Cover.
Turn the K3 so you can see the component side of the KIO3B main board and locate the USB/RS232
switch (see Figure 9). Place the switch in the USB/RS232 position as shown (toggle to the right looking at the
switch). This switch is used if you ever need to force a firmware load and have only a USB interface to your
personal computer (see Forcing a Firmware Download Using the USB Interface on page 13).
Figure 9. KIO3B USB/RS232 Switch.

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Replace the side panel on the K3 (see Figure 2 on page 6). If the K144XV is installed:
 Be sure the two TMP cables have not pulled loose from the KXV3 module (see Figure 10). Note the
location of the marked TMP cable.
 Carefully dress the cables into the notch in the KIO3B main board as shown in Figure 10.
 As you install the side panel, keep the cables above the K144XV module where you can reach the ends
to replace them in the K144XV connectors after the side panel is in place.
Hint: Stand the K3 on its side feet as you did to remove the panel and hold tension on the two
TMP cables for the K144XV to keep them in the notch while you put the side panel in place.
Then hold the side panel against the K3 until you have replaced at least two of the screws to be
sure the cables do not slip out of the notch.
 Reconnect the power connector to the K144XV.
 Reconnect the TMP cables to the K144XV module. For reference, complete cabling diagrams are shown
in Appendix A.
Figure 10. Positioning the TMP Cables in Preparation for Installing the Side Panel.