Its CNC Its Dynamite

I got rather excited this arvo and setup the mini cnc mill and went and bought some 1mm aluminium sheet with the grand idea to cnc out a front panel for the uBitx, because lets face it when it comes to cutting a straight line I suck big time. So i got on the computer and fired up Aspire Vectric and laid out a front panel with all the mounting holes etc being peck drilled for me to drill out to the right size later on the drill press. Things were going quite well until i realised i made it 100mm too short. Oh well, its now a tomorrow job.



Summer Corn Crop

Most things are having a hard time with the summer heat, but the corn is going great guns. I spaced the plants a little farther apart this time and offset them. Next time I am thinking of running a single row along the back of each bed as some of the ones at the back have not gown as fully as others, I am thinking its because they are being shaded slightly. We’ll see, its a work in progress.


Weather Station Data

So my weather station has been running for 21 days now on solar and batteries and other than a couple of glitches where it did not save any data its been running flawlessly. I have grabbed a copy of the data and ran it up in a spreadsheet and made a chart of the temperature data saved so far. Now this is by no means scientific accurate data, because the station itself is on the western side of my house, between two houses, but it is very representative of the micro climate of my vegetable garden, which due to being up against the house and the western aspect gets smashed in summer because of the heat and from what I can tell so far, tracks about 3 degrees C higher than the actual temperature. At the end of the month I will put up graphs for temp, humidity and barometric pressure as well as the raw data for the month.


RTL SDR Upconverter

So, it been a rather big week at work and I did not want to start something that will take me weeks to build and I thought I would get this done today in an hour or so and be testing it. Well one thing lead to another and I still need to make the low pass filter for it. Well that looks like a job for tomorrow. Nothing extraordinary here, 100mhz oscillator and ADE-1 mixer and a 5v power rail for the oscillator.


L Match With SWR Bridge Cont:

Putting the finishing touches to the antenna tuner project, I just need to cut the shafts down a little and put the knobs on. I have given it a test into 2 dummy loads, a dummy load and my 40m antenna LOL, and the led comes on super bright with 5w going in. All in all I am pleased with the outcome, though i would have preferred it in a smaller case, but the inductors use kind of determined the case it when in.



QRP L Match With SWR Bridge

So with the new year comes new projects, I am not going to set out what my overall plans and goals are as I have started way to many things and never bothered to see them through or to complete them. So with that in mind, I am building a L match

Its hard to make out, but you can just see the LED glowing, the signal is 10v p-p from the signal generator, the load is a decade resistance box. At infinite swr there is 1/2 the p-p voltage at the junction of the rectifier and capacitor. As swr approaches 1:1 the voltage drops to a point where the LED turns off. Its simple and its a winner.

It will get paired up with the sotabeams switched inductor and a 8-370pf air capacitor. as an L match. Should be good enough for the kinds of girls i go out with. Below is the schematic I am following for this project and a link to the authors site is at the bottom of the page. In the final build I will use 3w 50ohm resistors and the diode i used was a Schottky, i don’t recall the numbers it was just something i had in the parts box, I used the Schottky for its lower voltage drop, though that is probably not all that critical seeing that LED’s are current limited, not voltage.

Link to authors blog post: HERE



VK4FFAB Portable Station

So i finally got around to sticking the arduino logger into a box, and other than the fact that I cannot cut a straight line to save myself, it does not look all that bad and it will be somewhat protected now. I also spent some time aligning the IF on the Bitx 40. The software on the arduino vfo is code that I wrote and the display was always off by 1270hz. So i played with the IF frequency in the code and got it to be pretty close to being spot on. Its just about perfect on receive and so far no one has commented on the audio so I will take that as it sounds good enough that no one is going to get upset. Going to try and get out this weekend and activate a park or 2 for wwff.


LED Bezels

So months ago i bought 100 LED Bezels, it seemed like a good idea at the time and something i would later find use for. So today when i actually need one for a project, i go looking for them and cannot find them. It is not like my shit is a mess, its rather neat and tidy and somewhat organised with like things with like things. But can i find the LED Bezels, nope. No fucking idea at all and I have been through each and every tray looking for them.


Sotabeams Switched Inductor

This is an interesting little kit and not much information on the net about its use so I thought that I would add a quick blog entry about what I discovered about it. I am building an L match and started with the inductor. I really had no idea on windings, so i started with 6 turns and added 2 turns per inductor, with the 7th inductor having 18 turns on it. I spent about 20mins working out the switch, it is meant to be a 6 position switch, which in reality is a 10 position switch with a limiter. However in my case, it looks like i was given a 5 position 2 pole switch. While mildly annoying, with 5 positions I get 270nH -> 3.7uH inductance, and if i switch from the low side input to the high side input gives 1.7 -> 5.5uH, while adding switching is a pain in the arse, it is not the end of the world to have one inductor not in the loop. If i had realised before soldering in the switch i would have used a 10 position switch i have here and made it work right from the beginning. It is what it is, no use worrying about it now. 3.7uh is more than enough inductance for any antenna i build.



VK4FFAB Weather Station Up And Running

So the VK4FFAB weather station is all systems go. Well, kind of. I still need to put the front door on the box and make sure all the code is working and I also am still waiting on the water depth sensor for the rain fall gauge. So now the serious testing begins as I want it fully functional before the new year for data collection.

Once this is all done, I want to add environmental data monitoring for things like light intensity, UV, gas levels, dust levels and the like.