LIGHTEN UP: A New Entry On The Paddle Panorama
Special to The ARS Sojourner
Combining the need to have a trail-friendly Morse paddle for field operation
and a very lightweight instrument to keep the pounds off for ARS’
Spartan Sprints, I came up with the idea for the SPaddle.
It’s no coincidence that the name is a marriage of
the goals for SPs and code generation.
This vertical paddle weighs about 1/2 oz. and was made to fit and be taped
between screw heads under an Altoids box or to a logging clipboard.
With the operator’s hand resting on the box or base plate, code can
be generated with the SPaddle with the added bonus of single-handed stability.
That’s an especially good thing when you’ve already got your
hands full in many field operating conditions and positions.
You’ll see that it was designed for outdoor use, no matter what forecast
Mother Nature deals you. Too chilly to operate without gloves? The SPaddle
can be very accommodating. It is not intended to be the perfect paddle
for comfy indoor use. But it can sure make a difference on the trail.
The SPaddle is made from .032" thick, double sided, fiberglass printed
circuit board. It could be made from more common .062 stock but would
weigh more and the action will be stiffer.
Notching at the “contact island” will give it a lighter touch.
The SPaddle can be made to meet almost any circumstance as dimensions
are completely non-critical.
Contacts are made of No. 14 copper wire, soldered to the contact arms
and trimmed to fit before attaching the contact arms.
Contact spacing is adjusted by heating the solder and nudging the wire,
using a thin sheet of paper as a gap set.
An adjustable, but heavier alternative would be to turn the contact arms
parallel to the lever, solder a nut over a hole in each arm and use a
screw and locking nut – similar to a horizontal design in QST a while
back.
Copper is removed to form the “contact island” by cutting through
the copper (only) with an Exacto knife, heating the strip with a hot solder
tip and peeling it off. Thanks to Steve Weber, KD1JV, for that construction
tip.
The photographs show how the SPaddle is built and the cutting layout provides
nominal dimensions.
A “nibbler” was used to notch the paddle arm at the “contact island” to increase flexibility. A round file would work as well.
The wire and plug was happily liberated from a cheap pair of particularly painful stereo ear buds. Wires are passed through holes in the contact posts and knotted for strain relief. I use a dab of glue to anchor each knot in contact with its contact post to prevent torquing the fragile “hot” lead.
Note on the drawing that there is a GROUND WIRE shown, leading to the keyer. That’s chiefly to remind builders that the base of the SPaddle needs to be connected to the ground of your keyer.
In my version, the shielding in the stereo cable was used to make the ground connection. I soldered the shield to the bottom (grounded) portion of the paddle – below and separated from where the “hot” wire is soldered.
I’d recommend masking the contact area and spraying the SPaddle with clear varnish to preserve the shiny copper. Clear packing tape works too, but it’s more difficult to protect the whole thing.
After taking time to fine-tune and get the feel of SPaddle I’ve found it to be a good step toward the Spartan ideal. That, in combination with KD1JV’s remarkable “A-T Sprint” transceiver took first place in the Skinny Division for the April ‘03 Spartan Sprint, with a station weight of 12.3 oz.
Feel free to make improvements, and please don’t forget to share them with us!
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Seab Lyon, AA1MY, is a longtime QRPer, expert innovator and builder living in Bethel, ME. Via e-mail: sslyon@megalink.net