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Showing posts from November, 2022

Rockmite Log 22/11/29 : Antennas, broken keyers, and SWR meters

 Based on comments from the RSGB dipole antenna notes , I'm back to thinking I should try the ' radio in the middle ' dipole configuration for the Rockmite. The page mentions that the coax leading to a dipole can pick up a noticeable amount of noise without a balun. I have a Rockmite board already wired up this way. The issues with the radio in the middle mode of operation are: Biggest of all in this climate: moisture! I currently house the radio bare between the antenna wires. It's very, very foggy here on occasion. That, I suspect may also kill propagation though, so in its own way may not be an issue. Obtaining the necessary length of CAT-5 wire to carry power, audio, and keyer signals Tension relief for the antenna leads that hook directly into the board. (Especially important since the tree suspension system uses tree branches in conjunction with twine to support the antenna as close to horizontal as possible using increasing amounts of tension. On a pragmatic note

Rockmite Log 22/11/28: Antennas and Trees and Fishing Rods

 I set out to be a little more thorough in my antenna launching this morning. Here are the basic tools I used: It's been a busy weekend. Allow me to be more specific, I used a fishing rod with a weight tied to the end of the line, a spool of twine, and a pair of nail clippers. The steps were: 1. Toss the weight over a higher tree limb 2. Tie twine to the end of the fishing line with the weight 3. Pull the fishing line and the twine back over the limb 4. Detach the fishing line 5. Attach the antenna to the twine. 6. Use the twine to pull the antenna up towards the limb 7. Anchor the twine below. 8. Repeat with the other end of the antenna Here's 'a picture of the antenna's center when all was said and done So far, this hasn't been a better setup. No contacts, and no spots on the Reverse Beacon Network . I left the antenna in the tree, so I'll be updating throughout the day.

Rockmite Log 22/11/21 Looking at the transmitter output Also, Unschooling Thoughts

 I’m really enjoying WA4EFS’ website . The projects look like they were a ton of work, but the author melds all the various topics, analog, digital, and RF together so seamlessly, it’s easy to believe that they should be effortless works of love. In one of his videos he looks at the quality of the output radio wave from one of his transmitter project. It inspired me to do the same for the Rockmite.  I set up a dummy load: for the transmitter: two 1 Watt 100 ohm resistors. The pair, in parallel, gave me a total resistive load of 50 ohms, (=nominally speaking; (49.2 ohms once all the tolerances came into play).: I attached the dummy load to the Rockmite, then attached the scope probe across the resistors. I realized I might have an issue since I could only cause transmit by sending either a dot or dash with the keyer. I used the dash speed control to slow down dashes as much as I could, and tried the first experiment: sending a dash. The scope captured the waveform, and held it even afte

Ham Radio, Unschooilng, and Interests... So Many Interests

 Here's how it all starte.d This morning, I trudged out to the park with the little RockMite radio (a single frequency ham radio transciever that oerpates at 14.0577 MHz, we'll get to how I can be that certain soon), and started plunking out Morse code in hopes of reaching someone else on the same band. The view was gorgeous, and before too, too long, I made the second contact I'm made in over a decade with  WKJ7LVZ in Moab, UT! All of that was great! Also, the scenery over the antenna was pretty gorgeous. And here's where the unschooling interests start. First, the kids help me setup the antenna sometimes. They're aware that it's a half-wavelength dipole They've worked with waves both in Physics and electronics because of my partner and I. At the moment, they're learning Morse code. So, they're getting all the peripheral stuff you might expect from ham radio. Guess what else though?They're fascinated by the distances to the stations Icontact, a

Roll Dough at Sunrise!

 It's gorgeous outside over the Bay this morning, and? We're baking! Recipe! Ingredients 1/2 cup warm water   2 (1/4 ounce) packages active dry yeast   1 1/2 cups milk , lukewarm  1/2 cup sugar   2 teaspoons salt   2 eggs   1/2 cup shortening   7-7 1/2 cups flour   Directions Mix water and yeast in large mixing bowl.  Stir until dissolved.  Add milk, sugar salt, eggs, shortening and 1/2 of the flour.  Mix until smooth and pour out onto floured surface. Knead while adding the additional flour. Knead until smooth and elastic( about 5 minutes).  Round up in greased bowl with greased side up. Cover with damp cloth.  Let rise in warm place until double (about 1&1/2 hours).  Punch down; let rise again until almost double.  Dough is ready to to make into cinnamon rolls or dinner rolls now.

Rockmite Log 22/11/14 QSO to AZ!!!

 The little Rockmite worked! This afternoon, I sat down in McLaren Park nestled under a tree with the antenna suspended across two branches. The antenna was rougly parallel with John F. Shelley Dr., and as usual, the dipole was in fact pretty directional . Antenna tree: I could see the Hunter's Point Gantry Crane down the hill on the edge of the Bay. Sure enough, the line from the radio to Cottonwood, AZ (home of W7DVC goes right by it! All in all, the little radio reached out about 626 miles!

Rockmite Log 22/11/13

 First, the promised picture of the new keyer: I was operating the Rockmite on 20 meters QRP from McLaren Park this morning with the antenna tied between two trees. I started about quarter to 7, attracted the interest of one hiker who I chatted with briefly, and then got to listening. TLDR; the radio still hasn't made a contact. I did however hear some interesting stations: All of these maps are from the Reverse Beacon Network .

Rockmite Log 22/11/11

 I have, in the past, used this blog as a lab notebook. I'm not sure how intersting it all is to others, but it works out really well for me. So..... Yesterday, I changed out the keyer on the boxed Rockmite, (a single frequency radio kit available from qrpme . I'd used a set of switches I broke out of a junked TV for years, but they finally gave out.  Oh! I also built a new power cord for the rig. Here's the steps: The new power cord has a 9 volt battery connector on one side, but that's not what it's for. It attaches to these 12 volt AA battery holders we use. We: (Me and the 11, 10, and 9 year old gang.) With that accomplished, I set in on the key revamp. I removed the old keys. I'd forgotten that part of the reason I'd been so happy to have them was that they had screw nuts already built-in, making them easier to attach to the box: I remembered to take a picture of the color coded wires, from left to right at this angle, they are 'di', 'da

Boot Lace Shortage

 I bought a (for me) fancy pair of hiking boots this year. And, as usual, the first thing I trashed out was the laces. I don't know how I manage to do this? The kids? Sure, I figure they trash out their laces free-climging buildings, and in their other activities around town, I mean, uh, never mind. But me? Anyway, the laces are decaying quickly, and since these are (for me) fancy boots, I though it might be fun to spring for the $10 for the replacement shoe laces from the manufacturer. You know, original equipment and all that. But??? They're out of shoe laces! We now have shoe lace shortages... Oh well.

The Study of Telegraphy

 In unschooling, we run across a lot of literature and opinions about how to teach someone to read. Did you know, (I didn't), in 1897, there were studies about how to learn Morse code? I did not: https://grants.hhp.uh.edu/clayne/HistoryofMC/Bryan&Harter-1897.pdf The gang and I are starting in learning Morse this week (again). Watch here for more updates on how it's going. Our Morse practice site of the moment: https://www.aa9pw.com/morsecode/test/ Picture of a https://copaseticflow.blogspot.com/2008/11/casing-up-rockmite.html:

The Flying RockMite May Fly Again!

 Kind of wiped out by Halloween, a plethora of fun social activities, and other happenings over the last few weeks, so this'll be tre-short, but radios are back in the air... literally. The flying RockMite had power applied for the first time in about seven years this week, and immediately picked up K3ES from Cooksburg, PA, and another QSO in progress from Springfiedl, MO! The radio was located in San Francisco, so propagation on 20 meters seems to be pretty good in the afternoons right now. I haven't tried transmitting yet, but I'm looking forward to it!