Chasing a bug.

This post is once again 100% ham-centric, despite the fact that the title could just as easily apply to Linux, but I am working on some Linux stuff right now, and will do a Linux post soon.

After eight or nine years of having a membership in the Straight Key Century Club (SKCC) and not being very active with them, my interest has started to peak again this summer.  This was partially because of some of the people I met at LobsterCon this summer, and partially born out of a desire to just get on the air more.

I did participate for the first time in August in one of the SKCC monthly events, the Weekend Sprintathon, which was extremely enjoyable. Although it is a contest, it is very laid back, and most folks were operating at reasonable speeds (like around 20 WPM or less) which I find right in my copy-zone. This is unlike many more “official” contests where everyone is whaling away at 35 WPM and I have to listen to the exchanges for 8 or so contacts before I attempt a call. No, the SKCC events are quite relaxed, there is even time for some chatting as well as the exchange. After all everyone is using a hand key of some sort, so you really can’t go that fast.

Which brings me to the topic of this post. The SKCC rules of engagement are quite clear on what you can use to make a CW contact that counts toward an award:

Now I am mostly a straight key kind of guy, and in fact have a very nice collection of keys that has grown over the years. I regularly use three: a GHD key, a Kent KT-1 key, and a Hi-mound 709 key when operating from home. Portable, I have a Palm Portable key that works very well with the KX1. There are several others, and I drag them out and rotate through them because I like them all, and they all have a little different “personality.”

But I didn’t start my ham career with a straight key. I actually learned to send CW at first using an iambic paddle. It was one of those Bencher paddles with the long spring that loops around a post, and I used it with an MFJ keyer that fit on top of the paddle. This gear is long gone, but I still occasionally use paddles and a keyer — more so now that I am operating portable outdoors. The ergonomics of using a paddle are just easier when holding the whole station in your lap.

Anyway, while looking at the material on the SKCC website I started to think about the possibility of using a “non-straight” Morse appliance for making SKCC contacts. After all, there is some charm in that nice, side-to-side swing you use with a paddle, and it is less fatiguing. I looked around at some of the blogs of other hams talking about using “bugs”, and I started to think seriously about it. Uh-oh.

I should mention at this juncture that I have in my key collection a cootie key. It was made by LTA, a Spanish ham (EA6YG) who made very nice, heavy brass keys, and sadly passed away several years ago. It is a lovely key to look at, but I have to say that trying to send Morse with a cootie is nearly impossible for me. To do it correctly, you are supposed to start each Morse character with the same finger, and provide the timing for each component of the character with opposite swings of the key. (Wow, it’s not even easy to describe.) For example, to send “R”, dit-dah-dit, I’m supposed to make a dit with my forefinger, then a dah with my thumb, then a dit with my forefinger again. If the next character was a “K”, I would then send (after a suitable pause) a dah with my forefinger, then a dit with my thumb, then a final dah with my forefinger. Then collapse, twitching, on the floor.

It’s a diabolical device, and thinking about it is giving me a headache. Time to move on.

Now using a bug is kind of like using a paddle and keyer, if the dash input to the keyer was stuck. You make the dashes, it makes the dots. Bugs have a reputation of being very difficult to master, as they are a bit relentless in the dot making department and one’s timing has to be spot on. I had never considered using one before, being somewhat put off by all the bad press. Nevertheless, I thought I might like to give it a try. Uh-oh.

There then ensued several days of frantic eBay searching, checking online classifieds, and just missing some great deals. In a surprisingly short time though, I found a recently posted classified ad for a nice Vibroplex Champion bug, in good working order but needing some cleaning. Compared to prevailing eBay prices, the asking price was very reasonable, and I went for it. In hardly any time at all, I was the proud owner of a “new” old bug.

Original ad photo of my Vibroplex bug

Original ad photo of my Vibroplex bug

The first thing I did was completely disassemble and clean all the parts. The secret to being able to put it back together successfully, with no parts left over, is to use a digital camera and one of those plastic boxes with about thirty little compartments. Each assembly came off, went into the next consecutive box, and then I took one or more detailed pictures of the state of the key. Re-assembly was a snap, working through the boxes in reverse order and using the photos as a guide.

I carefully cleaned the base with soap and water and thoroughly dried it. Then each assembly was cleaned with a soft rag and Brasso. The only thing to avoid was any cleaning of the actual contacts — these I left alone. When the key was completely reassembled, I cleaned the contacts by closing them gently on a piece of writing paper, and then drawing the paper through the contacts. This is just abrasive enough to remove any oxide without excessive wear on the contacts.

The results of this total makeover were quite gratifying.

The next step was to adjust the various clearances and spring tension. I found an Youtube post describing how to do this, and followed the suggestions. At this point my bug was working fine, although there was the final bug problem to tackle: speed.

Semi-automatic keys were first made around the turn of the last century, as a way of assisting professional telegraphers in sending faster code without fatigue. To this end, out of the box they are set up to run at speeds starting around 25 WPM and ranging up to light speed, this range controlled by sliding a weight along the pendulum arm. The closer to the spring you move the weight, the faster the darn thing dits. It is quite common to modify the bug to slow it down, if you want to operate at more leisurely speeds. The modifications usually take the form of additional weights added to the pendulum arm; more mass at the end of the pendulum increases its period. In fact, for bugs currently in production you can purchase accessory weights for this purpose. For my bug, I had to improvise.

I tried adding some washers under the screw that holds the stock pendulum weight. This helped, and for a while I thought this would do the trick. I was testing the bug connected to a kit-built keyer set up for straight key mode, using the keyer as a code practice oscillator. Things seemed to be going well, but when I connected the bug to one of my radios, suddenly the dits were flying. I think the keyer was trying somehow to de-bounce the input, and rolling several dits together into one.

Using the bug with out additional weight was not possible: 25 WPM dots combined with 18 WPM dashes just sound weird. So, a custom weight fixture was a necessity. My design uses about an inch or so of the 4 feet of aluminum bar stock I got at Home Depot (the smallest quantity you can buy.) I drilled one hole to allow the knurled screw to hold the aluminum chunk to the pendulum. I drilled a second hole, and tapped it for a #10-32,       1 1/2 inch bolt. With the bolt screwed into the aluminum platform, I added #10 washers until the dits sounded like they went with the dahs. A wing nut holds the assembly together.

Closeup of homebrew weight

Closeup of homebrew weight

The resulting mod doesn’t look too bad, and the bug works great. I can send code just as badly with this arrangement as I can using a keyer and paddle!

My "new" bug, hobbled and ready to use.

My “new” bug, hobbled and ready to use.

It looks cool too. I especially like the red finger pieces. And the fact that it sounds like a treadle sewing machine while you are sending.

So once this was all set, I decided to try to see just how fast I was sending, so I called CQ a few times, hoping to be heard on Reverse Beacon Net.  Nothing. I guess my swingy, distinctive sending with the bug is unintelligible to a software Morse code decoder. But… someone came back to my call! Tom, K4ACK called, but he was really light, barely audible with QSB; we weren’t able to carry on much of a QSO. He started out at around 569, then disappeared completely, then came back a bit. But apparently he could copy my bug-generated code, so I’m calling it a success!

According to what I was able to find with a web search, my bug was made sometime around 1951. As it turns out, so was I — a perfect match.


de N2HTT



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