Dave Richards AA7EE

September 17, 2016

A Single Lever Paddle From QRP Guys

When building the SST for 20M, my plan was to kit it out with a paddle, battery, and an easily deployable antenna, and head for the hills. That’s still the plan. I don’t operate portable very often, preferring the comfort of the operating position in my small apartment, where I can make as many drinks and snacks as I want, and do it all with the company of my 3 kitties. Bliss! However, having just made a small, lightweight CW rig, I have to take it out in the field at least once in order to prove it’s mettle.

Currently, the only paddle I have is a Bencher, which is a bit too heavy and cumbersome to carry in my backpack for a portable set-up. There are some really neat portable paddles on the market, but I didn’t want to spend much, so settled on the idea of making one from PCB material, inspired by Wayne NB6M’s paddle, and KI6SN’s version, which was based on Wayne’s design. Two things happened to stop that idea in it’s tracks though. The first was that, nearing the end of building my SST, I was beginning to feel a bit lazy. Occasionally, when wading my way through a scratch-built project, I ponder how nice it would be to build a kit and give my brain a rest. At around the same time, I came across the website for The QRP Guys and realized I’d hit paydirt. They have a selection of small and low-priced kits for the QRP’er, including some small paddles made from PC board for very affordable prices. Perfect! The QRP Guys are Chuck Adams K7QO, Doug Hendricks KI6DS, Ken LoCasale WA4MNT, John Steven K5JS, and Dan Tayloe N7VE. Holy moly – that is some serious QRP starpower. I think we’d all be well advised to keep an eye on what these guys are up to.

QRP Guys ship out once a week on Wednesdays. With any small ham business such as this, where the owner/operators have many other things going on, setting expectations is an excellent idea. I decided on a single-lever paddle, and ordered it over the weekend. Later in the week, a small bag of parts arrived in the mail –

QRP Guys provide a scale for you to gauge how easy or difficult each of their kits is to build. On a scale of 1 to 5, with 5 being the most difficult, this paddle kit is rated as a 4. They do mention that some kits may also be rated as requiring what they term “expanded skills” – meaning, I assume, more difficult than 5. The rating of 4 for this kit makes sense. The PCB paddle parts need to be positioned fairly accurately. The way to do it is with a light tack solder in one point, re-adjusting until the exact positioning is reached, at which point you can commit with fully soldered joints. There are quite a few small screws, washers, and other small parts, so care, and a container to put all the small parts in are good ideas.

Here’s the final paddle. What a neat-looking little assembly –

A view of the underside –

This paddle is intended to be fixed to a panel, such as the side of a portable transceiver. I wanted it to be on a base, so decided to fabricate one from single-sided PCB material –

The cable is a cord from an old set of earbuds that came to an early end in the washing machine. It has a small molded 3.5mm stereo jack on one end, which is perfect for the task. It is held to the paddle base with a loop of twisted wire that threads through 2 holes in the base. At the point where it is secured, the cable was covered with 2 layers of shrink tubing. Luckily, the flexible wires in the earbud cord were insulated with heat-strippable enamel, so all that was necessary to remove the insulation was a generous gob of solder on the tip of the iron, and a few seconds, for the enamel to burn off –

You can’t see them, but there are 4 stick-on vinyl bumpers on the underside, purchased from the local Ace hardware store – the same type I used on the SST –

The copper is not lacquered, so if I take the same photo in a few months, it won’t look quite as shiny –

For size comparison, here’s the paddle with the SST20 and a pack of playing cards –

Despite the little stick-on feet under the base, I’ve found that the most comfortable way to send with this paddle is to hold it in my hand. This will work well for portable ops, when a suitable surface on which to place it might not be available. The lever is made from springy stainless steel. Doug Hendricks reminded me of an old tip for finding suitable flexible metal strips for making your own paddle, if you wish to do so. Just visit your local auto parts store and purchase a feeler gauge – the tool that is used for measuring spark plug gaps. It contains multiple flexible metal strips, of varying thicknesses (and degrees of springiness), so you can pick the exact one to suit your preference.

I experienced a small learning curve with this paddle. Firstly, I had never used a single lever paddle and secondly, I wasn’t used to the springiness of the lever, as most keys and paddles use stiff metal for the pivoting part. It doesn’t take long to get used to though. If you’re looking for a cheap and rugged paddle, this is a good value for the money. QRP Guys have both single lever and iambic paddles, with and without a base.

May 24, 2013

Taking Stock, New Desert Ratt 2 Recording, and A New Tut80 Run

When I started this blog almost 4 years ago, I was getting a (very small) handful of page views every day and had no idea that anyone would find it at all interesting or useful. In fact, I don’t think anyone did at first. Then I started building a few things and found that some people enjoyed looking at the pictures of my builds and in some cases, were encouraged to try building things themselves.

I used to think that in order to have a blog, website, or other kind of internet presence, you needed to be really, really good at something or it wasn’t worth putting your stuff out there, but I was missing the point. I think that the point is sharing. I don’t need to be one of the best at something, because everyone does things differently. If I do my best at something, and share the way that I did it, that information could well be useful to someone else who was trying to figure out how to do the same thing. Maybe my approach will present an interesting alternative to someone who was thinking of a different approach.

My last post on the NA5N Desert Ratt 2 Regen is quite a good example of this. I certainly didn’t design it so wasn’t offering anything radically new, but for anyone wanting to build one, there aren’t very many examples on the internet, with pictures, of DR2’s. Of the ones that exist, there aren’t a lot of detailed pictures, with discussion of construction details, all in one place. Perhaps someone was interested in building it, but was wanting to know the winding information for toroids (which doesn’t seem to be available online), or was wondering whether the tuning would be too fine, what kind of reduction drive to use etc. This is why I like to include this kind of information in my posts, in case it can help someone.

Since I sold my FT-817 2 years ago with a desire to rely more on homebrew gear, things have gone quite well. Admittedly the main rig at AA7EE has been a K2, which is not exactly home-brew, but it still felt good to prove to myself that I could assemble a kit of such complexity.

Apologies for the following 2 lackluster photos (it has to do with my inability in using flash to light indoor scenes, among other things) but here are the main bits of gear I have built in the last 2 or 3 years. These are the ones that worked; I left out the partially completed projects (which includes 2 DSB rigs that have working receivers but not fully working transmitters) .

On the top shelf, from left to right, is the 40M DC receiver using a Hi-Per-Mite filter, and an OHR WM-2 QRP Wattmer.

On the middle level is my K2, Fort Tuthill 80 (see news about a further release of Tut80 kits below), and the NA5N Desert Ratt 2 Regen.

On the bottom level you can see the Norcal 2N2/40, the first beta of the CC-20 and the first beta of the CC1 (it’s successor), both sitting on top of the G3WPO DSB80, and the N1BYT WBR Regen Receiver for 40M.

On the desk in front of that lot is a little 2 transistor TX on 7030 based on the Pixie 2 design. I have used it successfully with the WBR for a 100% home-brew on-air experience! –

The reason I arranged all these projects at my operating position and took their picture together is because I wanted to review my progress so far.  My interests are shifting, and it looks like ham radio will be taking a backseat to other pursuits for the next few months. This was a good way of putting a bookend on this period before I begin another one. This color shot shows why I usually drag my projects into outside light in order to photograph them.  I really need to work on my flash lighting skills (note the blown-out red channel on the freq displays – a bit of HDR work with Photoshop could have helped this, but sometimes I just want get on with things and post them!)

In other news, the videos I posted of the Desert Ratt 2 were intended to give a general sense of what this neat little regen is like to tune around the bands.  It doesn’t really give a good sense of what the audio from the receiver sounds like though, as I was using an MFJ-281 ClearTone speaker, which has a restricted audio response. On top of that, I was using the internal microphone of an old compact camera (Canon A80) to record it. To remedy this I made a recording the other night from the speaker jack of the DR2 directly into the line input of a little flash recorder (the Marantz PMD620, if you’re interested) and posted it to Soundcloud.  This will give you a much better idea of the quality of the audio from this receiver. Unfortunately, band conditions weren’t too good, so I wasn’t able to find any consistently strong signals with little in the way of QSB, but this recording of Radio Habana, Cuba isn’t too shabby.  It has been edited down, and the edit points are marked by cowbell sounds. When the signal gets strong, you can hear the wide frequency response and good fidelity of the Desert Ratt 2 –

And finally, I’ve had the pleasure of an e-mail chat with John K5JS, of the Arizona ScQRPions, and he informs me that they will be producing a final run of the Dan Tayloe designed Fort Tuthill 80 Direct Conversion CW QRP TX/RX. They already have the boards and many of the parts, so it sounds as if they just need to order some more parts and have a kitting party. This is no mean feat, as kitting is an awful lot of work. I don’t know when this will be happening, but it is definitely in the works. As you no doubt know, QRP Kits are selling versions of this rig for 15M and 160M, but I think it would be fun to buy another of the Tut80 kits when they come out and mod it for 40M. Has anyone done this? Could they post details of their mods to the Tut80 Yahoo Group if they have, perhaps?

In the meantime, the weather has been getting nicer and combined with the fact that the bands haven’t been in great shape, it’s as if mother nature is coaxing me to get out more. I plan to do just that. My bicycle has a new chain, and the weather is perfect for bike rides.  There’s also a new camera calling my name, which will require new photo software, and the inevitable upgrade of my operating system (I’m still on XP), as well as much time spent outside taking lots of pictures. I’ve been looking at my rather old photo portfolio and realizing that there is much work to be done, and much fun to be had.

Much work. Much fun,  I love it when the two go together 🙂

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