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Welcome to my home page. I became blind at birth. I started programming computers at a young age. I also earned my general class amateur radio license, KA3TTT, a hobby to which I have returned with great joy. I practice Qigong and consider myself a Taoist. I use Linux as my desktop and Android as my mobile OS. I eat gluten-free vegan meals. For the rest you'll have to read my blog.
My Vibroplex Bug
September 15, 2021The Straight Key Century Club (SKCC) does all of their work using mechanical Morse Code keys, as opposed to the electronic keys invented later. Most people will recognize the old telegraph key, where the person controls the dots and dashes. In 1905, Horace Martin had an interesting idea. He invented the semi-automatic key, which we call a bug.
A bug has a pendulum to form the dots. Pressing a paddle to the right activates the pendulum. Pressing the paddle to the left acts like a straight key for forming the dashes. If this sounds kind of strange then you have the right idea. This quirky instrument intrigued me, and I resolved to try one.
I took a trip to the Ham Radio Outlet in New Castle, Delaware. I wanted to try to return some things, and maybe buy some things. I met Ron and Mario, sorry I don’t have their calls. They did the best they could to accommodate my returns. If I had known that I only had ten days then I would have handled everything differently. Of course, then I wouldn’t have gone.
I asked about the Diamond X50A which I would eventually buy. I should have bought it on the spot, but I still didn’t quite know how I would mount it. As it turned out I mounted it perfectly on my window sill using the counterpoise as a tripod.
My friend Meg looked at some cool solar panels. I chatted with Ron and Mario. Eventually she asked if I had anything else I wanted to ask. We had driven there in the rain and they really did do their best with the returns. And admittedly, part of me wanted to buy something, like a kid at a toy store. I had an inkling.
“I’ve wondered about Vibroplex bugs. Do you have any?”
“Actually, we have a used one.” said Ron.
I knew I had to buy it. I asked if they could please take it out so I could touch it, since I can’t see it. I made it clear that I intended to buy it. They got it out and opened the box, and for the first time I touched a Vibroplex Original Standard Bug.
It really does feel like something invented at the turn of the last century, like an intricate pocket watch. It has a rectangular metal base. The pendulum arm sits towards the front of the base, with the paddle coming off the front. The paddle has two parts. On the left, it has a thumb-shaped piece of plastic. On the right, it has a plastic knob used for a straight key, but turned on its side, with the flat part facing outward. The pendulum’s weight sits at the back of the base under a metal hoop. The left side has three adjustment screws. The right side has one screw and the two contact screws for connecting it to your radio. Luckily I already had the proper cable. Vibroplex sells them. Perhaps coolest of all, you can hear the pendulum make the dots.
“It’s beautiful!” said Mario.
“That was Ken’s right?” one of them asked.
I learned that this key came from the estate of Ken Hartley, N2OHD, the former manager of the store. Meg recalled seeing a sign as we came in. He died at age 72.
“It’s as good as new. Ken was one of those hams who bought a lot of things and never used them.” said Ron.
“It’s beautiful!” repeated Mario.
I bought it and took it home, but quickly realized that I needed some help. I’ve adjusted all my other keys by touch, and figured if I fiddled with the screws enough then I would figure it out. Before I knew it I had reduced it to a nonfunctional mess. I emailed the SKCC. I knew they’d help, and sure enough they did. I received several helpful replies, and even offers for telephone training. One reply described the layout perfectly, and after some more fiddling I began to understand.
The bug sends and receives high speed code. I got it down to about 23 WPM, but I wanted to reduce it further. I purchased a Round Arm Vari-speed Accessory from Vibroplex. It adds an extra weight to the arm, but requires more adjustment. The heavier weight can cause bouncy dots. After a lot of practice I finally got it sounding good sending around 15 WPM.
The SKCC just had their Weekend Sprint, a relaxed contest which they have once a month. Each sprint has a theme, and for this month club stations counted for bonus points. I wanted to activate WM3PEN, the club call for the Holmesburg Amateur Radio Club. I had a headache most of the weekend, and I can’t do CW with a headache, but on Sunday night I felt well enough to drag myself on air, and to my delight I made three QSOs using my bug. I think Ken would have approved.
When a ham becomes a silent key as we euphemistically refer to it, the ham radio community distributes their equipment. I promise that his bug, now my bug, will get plenty of use.
Adjusting the Bug
I wanted to give a quick reference in case any other hams, blind or not, wander upon this article. As noted before, the bug has three screws on the left, and one on the right. They perform the following functions, going from front to back on the left.
- Dash gap
- Dot tension
- Dot pendulum gap
- Dot contact gap
The right side has the screw to set the dash tension. The weight goes on the arm and has a screw to tighten it. The closer to the end of the arm, the slower the speed. If you use the Vari-speed accessory, it screws on to the end of the regular arm, then the weight goes on that. The vari-speed has a screw which tightens it. Use the included allen wrench to unscrew it, slide it onto the main arm near the end, then position the vari-speed’s arm and tighten the screw.
Setting it requires getting a feel for the way the four settings relate. The dot gap and dash gap complement each other, as do the dot tension and dash tension. The dot gap and dot contact control the length of the dots. Many people get this wrong, resulting in so-called machine dots. Use an electronic key for reference. I first set the gap, then adjusted the contact, which also changed the tension. Easy does it… Each screw has a metal ring to lock it in place. Make sure to do this once you’ve found a good setting.
The pendulum requires a certain amount of space to get enough force to swing. If you set your spacing too narrow you won’t get a long string of dots, just a sad V. If you set it too wide it will cause extra force, then you will get bouncy dots. I’ve found that bouncy dots can also happen from setting the Vari-speed too far up the main arm.
I hope these notes help someone. I love the idea of sending high speed code mechanically. Why not!
Reducing HF Noise
August 03, 2021After my success using a ground plane, I discovered two other things which have further reduced my noise floor by 2 S-units. Firstly, I connected a 1:1 balun at the transceiver side. Secondly, I oriented the antenna for minimum noise. I will discuss both points.
When I got back into the hobby and began my battle against RFI, I ordered a 1:1 balun from Balun Designs. The description refers to connecting the balun outside of the shack, which to me sounds closer to the antenna. In an apartment none of that means anything. When I went on my Alpha Antenna Adventure, I disconnected the balun to eliminate any extra variables, and never got around to reconnecting it. A discussion about baluns led me to email the owner, and we had a short dialog.
I wondered if I had purchased the correct balun, and I had. He also suggested connecting it as close to the transceiver as possible. Did I connect it to the wrong end this whole time? Excitedly I grabbed the shortest length of coax I had and connected it. I instantly noticed the difference.
My noise floor dropped by another S-unit. Not only that, but my SWR improved on the higher bands. Previously I could get to an acceptable reading on 15 meters, but 12 meters and 10 meters would never tune below around a 2.6:1 SWR. For non-hams, SWR means Standing Wave Ratio, the amount of reflected energy coming back at you. You want it as low as possible, below 2:1. Now with the balun connected I could get down to a 2.1:1 SWR or sometimes a little better. Good enough.
A ground plane blocks signals below the antenna. A balun decouples the feed line so it can’t act like an antenna picking up noise. If you have a magnetic loop, you can make one more adjustment. A magnetic loop has a slightly directional property. You can take advantage of this in two different ways. You can either orient it for maximum signal or for minimum noise.
Instinctively we think about tuning for the maximum signal, but if you live in the gritty city, you may want to consider doing the opposite. Tuning for minimum noise will lower your noise floor. Don’t worry, you won’t miss out on signals.
The two things mentioned in this article, along with using a ground plane, have reduced my noise floor by at least 2 S-units on all bands. I have the reception I imagined that I would have. I don’t hear a horrible electrical hum if I tune to AM. I have a better SWR on the higher bands. I don’t feel a wave of depression when a wall of HF noise hits me. I hope these suggestions will improve your station as well.
Using A Ground Plane with a Magnetic Loop
July 15, 2021I love magnetic loops. They work well as an indoor antenna for an apartment. They have some interesting properties, and some little things to learn. I recently discovered the benefits of using a ground plane with one.
This began on the ElmerNet, which I run Wednesday nights at 07:00 PM on the WM3PEN repeater. Carl, N3ZZK, mentioned seeing more magnetic loops advertised in QST magazine. He mentioned a pretty wild looking one on DX Engineering. It has a microprocessor and interfaces with the radio’s data port. I noticed that the description mentioned that the loop comes with a mat made of metallic fabric to act as a ground plane This intrigued me.
For the non-hams, a ground plane acts as a substitute for the Earth, not exactly accessible from a second floor condo. A sheet of metal or a wire or series of wires perform the same function. The radio signals reflect off the ground plane, producing a mirror image of the antenna.
That weekend I got a chance to go up to the roof deck with my Elecraft KX3. I just brought my AX1, but I made a few contacts, and enjoyed the low noise environment. When I came back down and hooked everything back up to my Alpha Loop, the high noise level hit me like a wall, and a wave of depression followed. I had to do something about this horrible noise floor. I began searching, and saw a reference to using a ground plane under a magnetic loop.
I remembered Carl’s comment, and the magnetic loop which comes with a ground plane. I emailed Steve at Alpha Antenna, and he sent me a short article on his site which confirmed that using a ground plane boosted the signal by up to 5 dB. He also told me that it blocked noise on the other side of the plane. This excited me, because for me that means my downstairs neighbors and the street. The street has a trolley which they only run once a year to celebrate the Fourth of July, but they keep the power line active all year round.
. I called DX Engineering and asked if they would just sell me the ground plane mat, but they wouldn’t. I had to find a piece of metal suitable for my apartment. I asked my friend Meg and my brother. Both had pieces of metal. When I next saw Meg, we started brainstorming. I told her about the mat made of metallic fabric.
“Oh. Why don’t you just search for the fabric?” she said.
I went on Amazon and searched for Metallic fabric. I quickly found Faraday Fabric. People use it for making Faraday cages or RFID blocking accessories. It has metallic copper, metallic nickel composition, and polyester fiber. Perfect! They didn’t call it a ground plane, but I saw through the marketing. If it could block signals then it could act as a ground plane. I bought two sheets.
They arrived a few days later, and I eagerly lay them down. My friend Meg later helped me do it even better. I immediately noticed a drop in my noise floor by 1 S-unit, or 6 dB, maybe even a little more. On 20 meters I could copy signals down to S4 or S3. On 40 meters I could copy down to S6 or S5. The readability would often drop, but I still did it. I never gave out a signal report on 40 meters below S7, and I have the logs to prove it. I even saw a drop on 80 meters, the noisiest band. Before I would only hear S8 or S9 signals, and now I could hear down to S7. Amazing!
I wondered if I would see a similar increase in my effective radiated power. That weekend I played in the CQ WPX contest. We had bad conditions, but I worked 15 stations. I wanted one DX, and I worked a station in Germany, 4000 miles away. This happened on 20 meters using 5 Watts CW (Morse Code). We had to slow it down but we made it work! I can’t say that it has magically made me work everyone I hear, but I can hear more. Some better solar conditions would also help.
I would definitely recommend using a ground plane with a magnetic loop. Many people will use a metal screen or chicken wire, but this fabric installs easily and does a great job.
The HARC Elmer Net
March 19, 2021Recently, I began hosting the Elmer Net on the HARC repeater. In ham radio terms, a net works like a round table. A Central station called a net control takes checkins, then goes down the list, giving everyone a turn. In ham radio parlance, an elmer means a teacher. Hence, the Elmer Net lets people come and ask their questions. When I got back into the hobby I heard it a few times, then finally checked in and began asking questions.
Time went on, and Steve, W3AZT, the main net control, began hinting that he would have to stop running the net. A few of us said we might have an interest, but no one officially stepped up. I considered it, but only would do it if I had a backup. If I wake up with a headache I will not feel like running a net!
It came time for #100, Steve’s final net. Cliff, KC3PGT, said that he could not commit to running the net regularly, but he would volunteer as a backup. That gave me the confirmation I needed. The net wound down.
“Well, we’re coming to the end of the net, and nobody has stepped up, so I don’t know what will happen next week.” said Steve.
My turn had come to speak during the final round. I said that I would do it with Cliff as my backup. At first it felt surreal, but I have started settling in. It feels good to give something back to the hobby. I hope to see you there. You might even get a gold star!
Heil PR 20 Demo
December 17, 2020After hearing Dr. Bob Heil speak at HARC, I decided to upgrade my computer’s microphone. He joked that a lot of people use microphones that they say cost $40, and he responded that they sound like they cost $20. My microphone fell into this category. My ham radio station has a Proset 7 and an HM 12. Ham Radio Outlet had a good deal on a PR 20 utility microphone, so I snagged one. Listen to the difference! And no, the color of the mesh does not Affect the audio.
I immediately noticed that my voice sounds much fuller and brighter. I also noticed far less background noise. Incredible!