QRPGuys KX Single Lever Mini Paddle User manual

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QRPGuys KX Single Lever Mini Paddle
First, familiarize yourself with the parts and check for all the components. If a part is missing, please
contact us and we will send one. You must use [email protected] to request a part.
Parts List
1 – QRPGuys KX Single Lever Paddle PCB, 5 pieces in all
1 – J1, 2x2 female right angle header
1 – SS paddle leaf, 1.25” long
2 – 4-40 x 3/16”L thumbscrew
1 – 4-40 x 3/8”L SS pan head Phillips screw (used for soldering assembly holding)
2 – 4-40 x 1/2”L SS pan head Phillips screw
2 – 4-40 SS nut
2 – 4-40 brass nut
2 - #4 SS lock washer
2 – #4 SS flat washer
2 – 2-56 x 3/16” SS pan head Phillips screw
2 – 2-56 brass nut
2 - #2 SS lock washer
1 – 4-40 x 1”L pan head screw (used for soldering assembly holding)
1 - 1/2” wide x 2”L plastic shim
1 - 1/2” x 1” vinyl caplug
Even if you have done radio kit assembly before, please read through all the instructions before you start.
This kit is a little different, in that the mechanical components are parts of a printed circuit board. The
instructions give you the scope of the project and an understanding of the techniques we have employed.
You will be assembling the paddle from PCB material, and when assembled, also forms the electrical
connections. There are solder pads and registration marks that must be observed so that when you tack
and solder, it will make a sturdy mechanical and electrical assembly.
The tools you will need are a soldering iron with a small tip, solder, #1 Phillips screwdriver, needle nose
pliers, tweezers for the small hardware, cookie sheet, and a flat surface to work on.

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These are the five pieces and the names we will be using during the assembly.
It has been brought to our attention that on some boards there may be a extra trace connecting the top two
pads on the “Left Contact Holder” for the 2x2 in-line connector. Before assembly please check to see with
an ohm meter if they are connected. If they are, please cut the connecting trace between them with an
xacto knife, separating them electrically as shown in the graphic below. You may then proceed with the
assembly normally.

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Important:
On all the soldering you do, you will use the same technique. You tack a single tiny point
first and, then check to see that it is square and aligned with the registration lines and
other notes. It is easy to re-heat the joint and adjust the alignment when there is only a
single point. Then you tack the other pads, before you do the finish soldering.
First, check that the pins on the female header are bent 90º, and correct if necessary. Solder the 2x2
female right angle header to the left contact holder on the side with the silkscreen. Solder only one pin and
check for it being flush and parallel to the surface of the board, as shown in the graphic below. This is
necessary so it aligns with the internal contacts of the transceiver. Solder the rest of the pins and trim flush
with the back of the board.
Next in the assembly, are the two contact holders mated with the support. Using the 4-40 x 1” long
screw, assemble the two contact holders as shown in the figure below. You must adjust the nuts so that the
support just does fit between the two contact holders, flush with the front.

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Once all this is aligned and secured, place on a flat surface, and put a “small” tack between each contact
holder and the support. Leave the support screw in place.
Next, position the contact holder/support assembly on the paddle base with the registration marks, and
lightly tack a couple of points on the ends. The female 2x2 header should be centered in the cutout. If all
looks good, tack both sides of the holders, and alternate back and forth between the two sides adding a
little more solder. Finish soldering all the pads, and then remove the support screw.
Next, solder the two 2-56 brass nuts to the paddle leaf holder. Use the two 2-56 stainless steel screws to
secure the brass nuts on the side of the paddle leaf holder marked “nuts”, and solder the brass nuts to the
PCB. The lock washer insures that the nut will be flush with the PCB when it is heated. It is helpful to rub
the face of the nut on some scotchbrite or emery paper to clean up the surface contacting the PCB.
Next, position the paddle leaf holder with the nuts into the contact holder/support assembly as shown
below, flush with the top, bottom and paddle base assembly. And yes, it is supposed to be snug in the
support slot , to hold it in position while you solder. Tack one spot in place and check for alignment with the
registration marks, re-heat and adjust if necessary. Tack all the remaining pads, then finish soldering the
pads.

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Next, the two brass 4-40 nuts need to be permanently soldered to the “inside” of both the contact holders.
Use the 4-40 x 3/8”L SS screw, and, a #4 lock washer to hold them in place, and solder the brass nuts to
the PCB. The lock washer insures that the nut will be flush with the PCB when it is heated. Rub the face of
the nut on some scotchbrite or emery paper to clean up the surface contacting the PCB.
Assembling the paddle lever components:
It’s a good idea to assemble the hardware over a cookie sheet. Any hardware is difficult to find if dropped.
Secure the paddle leaf to the holder using the hardware as shown. The hardware is small but with some
patience and tweezers, can be assembled. It is easier to do the bottom screw first. Observe the order of
the hardware. There are two clearance holes in the right contact holder for a small screwdriver to tighten
the 2-56 screws. After assembly, if the paddle leaf holder is not perfectly square, the paddle leaf may be off
to one side, or on an angle. Simply bend it to be centered between the two contact holders. Center the
paddle leaf before installing the contact screws.
Cut the vinyl caplug lever cover 1/2” long from the closed end. Scissors will work easily. Cut the piece of
1/2” wide plastic into two 7/16”” long pieces. Sandwich the paddle lever between the plastic spacers and
slide the caplug over the end of the paddle leaf.

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Installing the contact screws:
Install the contact screws to each contact holder as shown. Observe the order of the hardware. The contact
distance to the paddle leaf can be adjusted from a few thousandths of an inch to whatever the user feels
comfortable with for sending. Start with a small clearance, and increase if needed. Secure the nuts when
satisfied.
This completes the paddle assembly. Use the two 4-40 thumbscrews to secure the paddle to the
transceiver.
Note: If you desire a stiffer feel or a lighter touch to the paddle, you can experiment with different paddle
leaf thicknesses. You can easily make a set of leaves from a simple set of feeler gauges. Most auto parts
stores or Harbor Freight carry an inexpensive set of 1/2” wide gages up to .030” thick.