ELECRAFT K3S User manual

ELECRAFT K3S
HIGH-PERFORMANCE
160 – 6 METER TRANSCEIVER
KIT ASSEMBLY MANUAL
Revision A, May 27, 2015
Copyright © 2015, Elecraft, Inc.
All Rights Reserved

3
Contents
Key to Symbols and Text Styles ............................ 4
Introduction ............................................................ 5
Customer Service and Support .................................. 5
Technical Assistance ............................................. 5
Preventing Electrostatic Discharge Damage ......... 7
How ESD Damage Occurs ........................................ 7
Preventing ESD Damage ........................................... 7
Preparing for Assembly ......................................... 8
Overview of the Kit ................................................... 8
Tools and Test Equipment Required ....................... 10
Unpacking and Inventory ........................................ 11
Screws ................................................................. 11
Standoffs ............................................................. 12
Lock Washers ...................................................... 12
Assembly ............................................................. 13
RF Board and Chassis ............................................. 14
RF Board Description ......................................... 14
RF Board and Chassis Assembly Procedure ....... 14
KANT3A or KAT3A Right Side and Rear Panels .. 22
KANT3A or KAT3A Description ....................... 22
Installing KANT3A or KAT3A Antenna
Connectors........................................................... 22
Installing KRX3 AUX RF (ANT) Connector ..... 23
Preparing Right Side Panel for Installation ......... 25
Mounting the KANT3A or KAT3A, Side and
Rear Panels .......................................................... 26
KXV3B Interface .................................................... 29
KIO3B Interface ...................................................... 31
KIO3B Description ............................................. 3 1
KIO3B Interface Installation Procedure .............. 31
Front Panel and DSP ............................................... 33
Front Panel and DSP Description........................ 33
Front Panel Assembly Procedure ........................ 33
Mounting the Sub Receiver Auxiliary DSP
Board ................................................................... 42
Installing the KDVR3 Digital Voice Recorder
Option .................................................................. 44
Mounting the DSP Board Assembly on the
Front Panel .......................................................... 45
Mounting the Front Panel Assembly ................... 47
Resistance Checks ............................................... 51
Initial Power On Check ....................................... 52
KREF3 Reference Oscillator ................................... 52
KREF3 Description ............................................. 5 2 
KREF3 Installation Procedure ............................. 52
KSYN3A Synthesizer .............................................. 55
KSYN3A Description .......................................... 55
KSYN3A Installation Procedure ......................... 55
Loudspeaker ............................................................. 58
Loudspeaker Description ..................................... 58
Loudspeaker Installation Procedure .................... 58
KPA3A Shield ......................................................... 60
KPA3A Shield Description .................................. 60
KPA3A Shield Installation Procedure ................. 60
Bottom Cover .......................................................... 62
Bottom Cover Description ................................... 62
Bottom Cover Hardware Installation Procedure .. 62
KNB3 Noise Blanker Description ....................... 64
KNB3 Installation Procedure ............................... 64
KBPF3A General Coverage Receive Option ........... 65
KBPF3A Description ........................................... 65
KBPF3A Installation Procedure .......................... 65
Power Amplifier Jumper Block ............................... 66
Battery BT1 ............................................................. 67
Battery BT1 Description ...................................... 67
Battery BT1 Installation Procedure ..................... 67
Finishing the Enclosure ........................................... 68
Fan Opening Cover .............................................. 68
AUX RF Cable .................................................... 68
Bottom Covers ..................................................... 68
Top Cover ............................................................ 71
Test and Calibration ............................................. 73
Initial Power Checks ................................................ 73
Synthesizer Check ................................................... 73
Filter Setup .............................................................. 74
Reference Oscillator Calibration ............................. 74
TX Gain Calibration ................................................ 74
Option Modules ....................................................... 75
Enable Modules ....................................................... 75
KPA3A 100-Watt Amplifier Installation ................. 75
KRX3A Sub Receiver Installation ........................... 75
Other Calibration Procedures .................................. 7 5 
Wattmeter Calibration (Optional) ............................ 75
S-Meter Calibration (Optional) ................................ 7 5 
Appendix A, Illustrated Parts ist............................... A1
Elecraft manuals with color images may be downloaded from
www.elecraft.com.

4
Key to Symbols and Text Styles
Identifies important information.
-100 Characters displayed on the LCD screen
DISP Tap switch function (labeled above a switch)
AVERAGE Hold switch function (labeled below a switch; hold for 1/2 sec. to activate)
MENU:Font Typical menu entry

5
Introduction
This manual will guide you through assembly of your Elecraft K3s transceiver. We’re confident that you’ll find
the K3s easy to build, even if you’ve had no prior kit-building experience.
Every modern transceiver is complex, and the K3s is no exception. The kit includes nearly 300 individual
components, including over a dozen PC boards and a multi-element modular chassis. But the unique design of
the K3s eliminates some of the tedious aspects of construction, enabling you to complete assembly in far less
time than previous high-performance transceiver kits. Also, virtually all of the alignment is handled in firmware
using test capabilities built into the K3s.
If you should you have difficulty, you'll have our full support via phone and e-mail. In addition, we hope you'll
join our growing and enthusiastic community of owner/builders via the Elecraft reflector.
Further information about the Elecraft K3s, including specifications, installation, and operation instructions, can
be found in the Owner’s Manual.
Elecraft manuals with color images may be downloaded from www.elecraft.com.
Customer Service and Support
Technical Assistance
You can send e-mail to [email protected] and we will respond quickly - typically the same day Monday
through Friday. Telephone assistance is available from 9 A.M. to 5 P.M. Pacific time (weekdays only) at
831-763-4211. Please use e-mail rather than calling when possible since this gives us a written record of the
details of your problem and allows us to handle a larger number of requests each day.
Repair / Alignment Service (We want to make sure everyone succeeds!)
If necessary, you may return your Elecraft product to us for repair or alignment. (Note: We offer unlimited email
and phone support to get your kit running, so please try that route first as we can usually help you find the
problem quickly.)
IMPORTANT: You must contact Elecraft before mailing your product to obtain authorization for the
return, what address to ship it to and current information on repair fees and turn-around times. (Frequently we
can determine the cause of your problem and save you the trouble of shipping it back to us.) Our repair location
is different from our factory location in Aptos. We will give you the address to ship your kit to at the time of
repair authorization. Packages shipped to Aptos without authorization will incur an additional shipping charge
for reshipment from Aptos to our repair depot.

6
Elecraft's 1-Year Limited Warranty
This warranty is effective as of the date of first consumer purchase (or if shipped from factory, date product
is shipped to customer). It covers both our kits and fully assembled products. For kits, before requesting
warranty service, you should fully complete the assembly, carefully following all instructions in the manual.
Who is covered: This warranty covers the original owner of the Elecraft product as disclosed to Elecraft at
the time of order. Elecraft products transferred by the purchaser to a third party, either by sale, gift or other
method, who is not disclosed to Elecraft at the time of original order, are not covered by this warranty. If the
Elecraft product is being bought indirectly for a third party, the third party's name and address must be
provided to Elecraft at time of order to insure warranty coverage.
What is covered: During the first year after date of purchase, Elecraft will replace defective or missing parts
free of charge (post-paid). We will also correct any malfunction to kits or assembled units caused by
defective parts and materials. Purchaser pays inbound shipping to Elecraft for warranty repair, Elecraft will
pay shipping to return the repaired equipment to you by UPS ground service or equivalent to the continental
USA and Canada. Alaska, Hawaii and outside U.S. and Canada actual return shipping cost paid by owner.
What is not covered: This warranty does not cover correction of kit assembly errors. It also does not cover
misalignment; repair of damage caused by misuse, negligence, or builder modifications; or any performance
malfunctions involving non-Elecraft accessory equipment. The use of acid-core solder, water-soluble flux
solder, or any corrosive or conductive flux or solvent will void this warranty in its entirety. Also not covered
is reimbursement for loss of use, inconvenience, customer assembly or alignment time, or cost of
unauthorized service.
Limitation of incidental or consequential damages: This warranty does not extend to non-Elecraft
equipment or components used in conjunction with our products. Any such repair or replacement is the
responsibility of the customer. Elecraft will not be liable for any special, indirect, incidental or consequential
damages, including but not limited to any loss of business or profits.

7
Preventing Electrostatic Discharge Damage
There is no climate or work location where the components of your K3s are safe from Electrostatic Discharge
(ESD) unless you take specific steps to prevent such damage. Many of the components in your K3s can be
damaged by static discharges of only a few volts: far too little for you to notice. It is those low-voltage but
destructive discharges that easily happen anywhere and under virtually any environmental conditions.
ESD damage may not be apparent at first. The damaged components may not fail completely. Instead, the
damage may result in below-normal performance for an extended period of time before you experience a total
failure.
How ESD Damage Occurs
Whenever an object containing a static charge touches a circuit in your K3s, current will rush into the circuit
until the components reach the same voltage as the source of the static charge. If the voltage or current that
passes through a component in your K3s during that brief period exceeds its normal operating specifications, it
may be damaged or destroyed.
Preventing ESD Damage
ESD damage cannot occur if there is no voltage difference between the components in your K3s and any object
that touches them. That is how anti-static packaging works. Anti-static bags allow the static charge to flow over
their surface, so that any part of the bag that touches the components inside are all at the same potential at all
times. Anti-static foam keeps the leads of sensitive components at the same potential.
At your work bench, avoiding a dangerous voltage is achieved most easily by tying everything together and
connecting them to a common mains safety ground. This includes your K3s, individual boards or other sensitive
components as well as everything they may touch at the work table.
Inexpensive static dissipating work mats are readily-available that will steadily and safely drain off any charges
built up on parts or circuit boards placed on them. They are supplied with a lead that connects the mat to the
common workbench ground. Also, metal cabinets on test equipment used on the bench should be tied together
and connected to the common ground.
Most importantly, you must have a way of continuously draining off any static charges that occur on your body.
Such charges are easy to create, even while sitting quietly at the work bench. Moving your feet on the floor,
shifting position in your chair or even moving your arms so that clothing rubs against itself can all produce
destructive static charges. You can discharge yourself by touching an unpainted metal ground, but that will last
only until you move in a way that produces a new static charge. The safest technique is to wear a grounded wrist
strap with a series 1-megohm resistor that continuously drains off any charges. Such wrist straps are readily-
available and inexpensive.
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.

8
We strongly recommend you take the following anti-static precautions (listed in order of importance) to avoid
trouble:
 Leave ESD-sensitive parts in their anti-static packaging until you install them. The packaging may be a
special plastic bag or the component’s leads may be inserted in conductive foam. 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
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. DO
NOT attach a ground directly to yourself as this poses a serious shock hazard.
 Use a grounded anti-static mat on your work bench.
 If you choose to use a soldering iron to work on your K3s for any reason, be sure the iron is ESD-safe
with a grounded tip tied to the same common ground used by your mat or wrist strap.
Preparing for Assembly
Overview of the Kit
The kit comprises two major assemblies: the main chassis and the front panel. Figure 1 shows an assembled
K3s/10 with its top cover removed.
The main chassis is literally built up around the RF circuit board, which fills the entire bottom of the unit of the
chassis assembly. Panels are mounted around the RF board using Elecraft’s 2D fasteners. These fasteners allow
individual removal of any one panel, if needed, to gain access to the inside of the radio for servicing. Very few
cables or wires are used in the kit. Most of the other boards and optional accessories plug directly into the RF
board or one of the boards mounted on the RF board.
The front panel assembly, including the display and main operator controls, includes the front panel board and
the digital signal processing (DSP) board.
There are many options that you can add to the basic K3s/10, such as the 100 watt amplifier module, internal
antenna tuner, second receiver, additional crystal I.F. filters, etc. If you purchased these options with your K3s
kit, you will find instructions to install them at proper places in the assembly procedure to make getting your
complete K3s together and operational in the most efficient manner.
Many of the pc boards in your K3s kit look slightly different from those
shown in the illustrations in this manual. Your kit contains the new K3s
boards while many of those shown in the illustrations are the original K3
boards.

9
Figure 1. Typical Assembled K3s/10 (Less Top Cover and Chassis Stiffener Bar).

10
Tools and Test Equipment Required
1. #0 and #1 size Phillips screwdrivers. To avoid damaging screws and nuts, do not use a power
screwdriver. Use the screwdriver that best fits the screw in each step.
2. Soft cloth or other surface to lay cabinet panels on to avoid scratching. A clean static-dissipating mat is
ideal (see below). If using cloth, do not lay circuit boards on it. See Preventing Electrostatic
Discharge Damage on page 7.
3. Pliers or suitable wrenches for tightening 1/4”, 3/16” and 1/2” nuts. The 1/2” size is used to tighten nuts
on the front panel controls. If available, a deep socket or nut driver is recommended. Pliers or an
ordinary wrench can be used, but requires care to avoid damaging the front panel paint.
4. Long nose pliers.
5. Diagonal cutters.
6. Small rule capable of measuring lengths up to 1” (2.5 cm) with an accuracy of at least 1/16” inch
(1.6 mm).
7. Digital Multimeter (DMM) for resistance checks.
8. RF 50-ohm, 5 W (minimum) dummy load with low VSWR from 160 meters through 6 meters.
9. Power supply 13.8 VDC nominal (11-15 V) with a cable and Anderson PowerPole® connector. A power
cable kit is provided with your K3s if you do not have a suitable cable with the required Anderson
PowerPole connector. The power supply must be capable of providing at least 3 Amperes for a K3s/10
and 20 Amperes for a K3s/100. (See Specifications in your Owner’s manual for more information on
power supply recommendations).
The following tools are strongly recommended:
1. ESD wrist strap.
2. Static dissipating work mat.
Optional Equipment:
1. RF Power Meter with accurate readout from 1 mW to 5 watts, minimum.
2. Signal generator with calibrated 50 µV output at 20 or 40 meters.
In addition, two Allen wrenches, 5/64” (2mm) and .050”, are supplied with your kit.

11
Unpacking and Inventory
CAUTION
Do not handle the circuit boards without anti-static protection! Doing so may damage
sensitive components. See Preventing Electrostatic Discharge Damage on page 7 for important
information before proceeding.
Before starting construction, do a complete inventory, comparing the parts in your kit with the parts list in
Appendix A, to familiarize yourself with all of the parts and to ensure the kit is complete. When inventorying,
look in the sealed envelopes to identify their contents, but not mix them up. Some screws are very similar in
length, but must be used in the correct locations described in the procedure to avoid damaging your K3s. Other
screws are stainless steel to be used on the outside of the enclosure. Note that a few extras of some screws, nuts
and washers may have been included on purpose.
All dimensions given in the assembly procedure are provided in both US customary (often called English) and
metric measurements. The native dimensions of the parts are in US Customary units. Approximate metric
equivalents are given to assist those more familiar with that system to identify the correct parts.
Screws
A number of different types and sizes of screws and washers are used in the assembly. It is very important that
you use the screw specified in each location or your finished K3s may not fit together properly. In some places,
using the wrong size screw may damage components. The following various screw types and sizes specified in
the text are shown in Figure 2. Images are shown for comparing relative sizes. They are not to scale. The lengths
of the screws called for in the text are measured as shown.
Figure 2. Screw Sizes Used in Assembly.

12
Standoffs
A number of threaded standoffs are used. As with the screws and washers, be sure you use the correct size as
specified in the text. Standoff lengths are measured from end to end as shown in Figure 3. Standoffs threaded for
2-56 and 4-40 screws are used.
Figure 3. Typical Standoff.
Lock Washers
Two types of lock washers are used in the K3s (see Figure 4). It is important that you use only the type specified
and put the washers exactly where indicated. Failing to use the correct type may result in short circuits to nearby
circuit traces. Adding washers or placing the washers in the wrong position may cause parts to fail to fit together
properly.
Figure 4. Lock Washers.

13
Assembly
IMPORTANT ASSEMBLY INFORMATION
1. Screws and other Fasteners: A variety of screws and fasteners are used to assemble your K3s:
 Stainless Steel Hardware: Exterior screws are stainless steel to avoid corrosion in harsh
environments. The stainless steel screws and washers are packaged in a separate bag marked
E850714 SS Hardware Kit. Do not mix them up with the other screws in the kit. The letters (SS)
are included in the procedure wherever you should use a stainless steel part from that bag.
 Use your rule to check the length of screws and standoffs before installing them. Some
components are only 1/16” different from others but using the wrong size may result in parts not
fitting correctly, possibly damage electrical and mechanical components. See Screws on page 11
and Standoffs on page 12 for more measurement instructions.
 Loosen screws as needed for a proper fit. When mounting parts with multiple screws or
adjacent parts that fit together, such as the exterior cabinet panels, loosen adjacent mounting
screws as needed to adjust the parts for the best fit. Be certain you re-tighten the screws before
proceeding.
 Ensure all screws are tight. A loose screw can cause both mechanical and electrical problems
such as intermittent operation, unexpected noise or false signals (birdies) in the receiver.
 Threads can be easily stripped if too much force is applied when tightening screws. Use the
correct size hand tool and apply only moderate torque. Do not use a power screwdriver!
2. Brief circuit descriptions are provided through the manual for those interested in the functions of the
circuits. For more detailed circuit information, consult the Theory of Operation in your Owner’s
manual.
CAUTION – TO AVOID DEGRADING THE PERFORMANCE OF YOUR K3s:
DO NOT DISTURB ANY ADJUSTMENTS ON THE BOARDS!
Each board was tested and aligned for optimum performance at the factory. Any change to
these adjustments will degrade the performance of your K3s or prevent its operation
altogether. All user calibrations and adjustments are done in firmware using the front panel
menus. These are described at the appropriate points in the assembly procedures.
DO NOT ADJUST THE TURNS ON ANY TOROIDS!
The position of the turns on the cores of many toroids has been adjusted at the factory to
produce exactly the inductance needed for the circuit to work properly. Any attempt to
adjust their position or to make a coil look “nicer” may seriously degrade circuit
performance.
Also, do not attempt to fix the turns or coils in place with adhesives or other materials.
Those toroids needing support have been fixed at the factory. Adding material to the other
toroids will alter their inductance, again degrading circuit performance.
ESD SENSITIVE!
Observe ESD precautions when handling the circuit boards and whenever you are working
on your K3s with the covers off. Failure to observe ESD precautions may result in your K3s
not operating at all, or operating but not meeting normal factory performance
specifications due to damaged components. See page 6 for more information.

14
RF Board and Chassis
RF Board Description
The RF PCB (Printed Circuit Board) is the heart of the K3s transceiver, both physically and electrically. During
assembly, it serves as an attachment point for other PCBs as well as chassis panels, acting as the glue that holds
things together. During operation, the RF board provides signal routing to and from all modules. For more
information, see Theory of Operation, RF Board, in the K3s Owner’s Manual.
RF Board and Chassis Assembly Procedure
CAUTION
There are components on both sides of the circuit boards. When handling them, be careful not
to damage components on either side by placing the board on top of tools or other objects, or
bumping or crushing the components while mounting parts or installing the boards
Remove the RF board from its anti-static packaging. The top side of the board is the side with the toroid
inductors and relays along with other components, including several connectors along one edge. The edge with
the connectors is the back edge of the board, while the front edge has notches cut in it that will fit around front
panel controls. Locate the six rectangular bare copper pads for the 2D fasteners (see Figure 5). There is one in
each corner of the board and one in the center of each side (see Figure 11 on page 18).
Figure 5. 2D Fastener Location on RF Board.
Install 2D fasteners at the six spaces provided (one at each corner and at the center of each side of the RF
board). Mount the fasteners on the bottom side of the board as shown in Figure 6. Be sure the 2D fasteners are
oriented so the side of each fastener lines up with the edge of the RF board as shown.
Figure 6. Installing 2D Fasteners on RF Board.

15
Install a 4-40 3/8” (9.5 mm) standoff on the RF board near connector Z1 as shown in below and Figure 11
on page 18. This standoff will support the mixer to be installed later. Install the standoff using three lock
washers as shown below with two of the lock washers between the standoff and the RF board.
CAUTION: To avoid damaging the circuit trace between R74 and the metal ring around the mixer
standoff screw hole, position the lock washer under the screw head with the split facing away from the
trace, then tighten the assembly by turning the standoff while holding the screw and lock washer
stationary.
Figure 7. Installing Mixer Standoff.
Install the two KBPF3A standoffs shown in Figure 8. Even if you didn’t purchase the KBPF3A general
coverage option, the standoffs and hardware are included in the K3s kit to make installing the option easier at
some future date. Note that these standoffs have only one lock washer between each standoff and the RF board
Note that one standoff is very close to the toroid coils. The standoff may touch the coil. That will not
affect circuit performance. If you wish, you may adjust the position of the coil slightly to avoid contact. .
Figure 8. Installing KBPF3A Standoffs.

16
Install hardware to attach Q3 to the RF board near the rear left corner as shown in Figure 9 and Figure 11
on page 18.
Figure 9. Installing Q3 Hardware.
Locate the crystal I.F. filter(s) that you purchased with the K3s. At least one I.F. filter must be installed for
the K3s to operate. Two types of filters are available: standard 5-pole filters and optional 8-pole filters (see
Figure 10). If you plan to add filters later, spaces may be left for them. For example, if you plan to add the FM
or a 6 kHz AM filter later, you can leave spaces FL1 and FL2 open for them and install the 2.8 kHz filter in
position FL3. The filters are not hard to move about later, so if you aren’t sure, install the widest at FL1, the next
widest at FL2 and so on.
Enter the following data on Table 1.You will need this information to set up your filters after assembling
your K3s. Be sure you’re following the rule described in the step above about the proper order for the filters.
Note that Table 1 is set up with FL1 to the right and FL5 to the left, just as they must be installed on the RF
board.
Enter the bandwidth of each filter in the row below the filter position in which it will be installed.
Enter the FREQ OFFSET shown on each filter. The optional 8-pole filters have no offset marked on
them. Enter a zero in the FREQ OFFSET column for those filters. For the 5-pole filters, note that the
frequency offset may be negative, indicated by a minus sign (single dash) ahead of the number.
Table 1. Filters Installed.
Note: FL1 is to the right and FL5 is to the left. In the next step you will install the filters
right-to-left on the RF board as well.
POSITION FL5 FL4 FL3 FL2 FL11
BANDWIDTH2
FREQ OFFSET3
1. If you’re installing the KFL3B FM filter, place it in FL1 position since it is the widest bandwidth
filter available.
2. The bandwidth is shown in the label attached to the filters except the K-FL3B FM filter. Record a
bandwidth of 13 kHz for the KFL3B FM filter.
3. All of the optional 8-pole filters have an offset of zero. Note that the 5-pole filters may have a
negative offset, indicated by a minus sign ahead of the number.

17
Install the filters as shown in Figure 10. Refer to the list of filters you created in Table 1 to determine which
filter to install at each location.
CAUTION
1) Do not use screws longer than 1/4” (6.4 mm) to mount the filters. Use your ruler to
measure the screws before installing them. Longer screws may extend into the optional 8-
pole filter and destroy it. We strongly recommend you use a 1/4” screw even when installing
the 5-pole filters to reduce the possibility of damaging an 8-pole filter should you change
them later.
2) Do not over-tighten the screws. Too much torque may pull the threaded bushing out of
the bottom of the filter module.
Figure 10. Installing Crystal I.F. Filters.
Locate the K3s top cover. On the inside is a label with places to record the bandwidth (BW), and frequency
offset (FRQ) of each filter. Copy the information from Table 1 and place a check mark by Main (for main
receiver) on the label. Use pencil in case you change your filters later. This will keep the filter information with
your K3s. The label also has a row for Gain. This is a value you can determine later after your K3s is assembled
and aligned. It is a value set in the K3s’s MENU to adjust the overall gain for each roofing filter so the audio
remains constant when switching from one filter to another. Making this adjustment is described under Filter
Loss Compensation in your owner’s manual.

18
Figure 11. RF Board Partially Assembled.

19
Install the Low Power Amplifier (KLPA3A) board in the cutout on the RF board as shown in Figure 12.
The board is held in place by its connectors until the bottom cover is installed.
Figure 12. Installing the KLPA3A Low Power Amplifier.
Check all three KLPA3A connectors shown in Figure 12 to ensure they are fully mated as shown. If they
are not fully mated, the transistors will not rest against the K3s bottom cover as required when it is fitted later.

20
Mount a 2D fastener on each ear of the front panel shield, and then mount the shield on the RF board as
shown in Figure 13. Be sure the 2D fasteners are oriented with the widest part between the two holes and the
edge toward the outside as shown.
Figure 13. Installing Front Panel Shield.
Mount the K3s mixer board on the RF board as shown in Figure 14. The mixer plugs into Z1 on the RF
board.
Figure 14. Installing Mixer Board.

21
Locate the two side panels. They are approximately 4” (10 cm) by 9-7/8” (25 cm) in size. Both panels have
six counter-sunk screw holes near the edges. Note that the countersunk holes are farther from one end than the
other. This is important. You will need to orient the panels correctly as you install them. The side panels are
different as well. In addition to the six counter-sunk screw holes, the left side panel has two holes near the
centerline for attaching the handle and three larger counter-sunk holes near the top edge. The left side panel with
the handle attached is shown in Figure 16. The right side panel has six additional holes; four for mounting the
side feet and two for attaching other parts inside the K3s (see Figure 21). Set the right side panel aside for now.
Check the inside (partially painted) of both panels to ensure no masking tape is covering any screw holes. If
found, peel it off.
Attach the handle to the left side cover using the hardware shown in Figure 15 at each end. The ribbed side
of the handle faces away from the panel. Tighten the screws enough to compress the lock washers, but do not
tighten the screws so much that you deform the handle end cover. The handle should move easily to allow room
for your fingers between the handle and cover for carrying, then lie flat against the cover when it is not in use.
Figure 15. Installing Side Handle Mounting Hardware.
Install three 6-32, 1/4” (6.4 mm) screws in the larger holes in the side panel shown in Figure 16. Use a #6
nut and split ring lock washer on the inside to secure each screw. These holes are for mounting the optional
K144XV 2-meter module. The screws are provided to fill them when the option is not installed.
Attach the left side panel to the RF board assembly as shown in Figure 16 using five 4-40 3/16” (4.8 mm)
black flat head screws (SS). Do not use washers. When oriented correctly, the edge of the panel will extend
about 1/2” (13 mm) past the 2D fasteners at the front panel shield. If needed, loosen the screws attaching the 2D
fasteners to the RF board or front panel shield for best alignment. Tighten them again after the side panel is
installed.
Figure 16. Mounting Left Side Panel.