Posted on July 18, 2017
The Raspberry Pi Zero W on the left, and the Raspberry Pi 3 B on the right
The “regular” Raspberry Pi – on the right – is about the size of a credit card. So its even more amazing that a full on Linux machine can be even half that size, and have WiFi built in for only $10 US.
For the u.RAT project I certainly don’t need a monitor or keyboard, so I will configure the Raspberry Pi Zero W to boot up and automatically run the urat program. Since it boots in WiFi – I just ssh into it and can gracefully shut down the computer before turning off the console that will house it.
To create a Raspberry Pi Raspian Jesse Lite OS boot SD card, I used a well known utility (Etcher) and procedure – format the card then use Etcher to flash an image (that I downloaded from Github).
Here’s a super important tip:
If you don’t first format the SD card and get a good boot image the Raspberry Pi Zero W will look dead. I thought mine was zapped and it was just because I did not flash the SD card right. When the boot disk is good, the tiny green led will flash.
Ssh and WiFi ….
I then used sudo raspi-config to enable ssh and finally added this text:
ssid=”Your WiFi name”
psk=”Your WiFi password”
to the /etc/wpa-suplicant/wpa_supplicant.conf file. I used my WiFi name and security key of course. Run ifconfig and see if the router is found and that you have an ip address.
I still needed one last command:
sudo route add default gw 192.168.1.1
Posted on July 17, 2017
I heard Tom, ZS1AFS on the morning 40M Long Path, which is the first time in what seems like a month or maybe even two. I don’t know if this is true every year, but my guess that this path isn’t that great around the Northern Hemisphere summer solstice – at least this year. But you would think that then it would also suffer during the Northern Hemisphere Winter solstice.
I’m starting to think its been just an anomaly this year because I think the ZS path is open most of the year. I don’t remember it closing so much last year.
Posted on July 16, 2017
We are a few weeks away from a Celtic calendar day called a Cross Quarter Day. It’s the half way point between a solstice and an equinox. Agriculturally, it’s the very first part of the fall harvest.
As a father of two boys that went to Acalanes in the Lafayette school district, I clearly remember July 15 being halfway between end of school and beginning of next school year.
I looked at the Sunrise – Sunset site and notice that we lose more than 1/2 hour of daylight between now and August 1. It’s the start of an acceleration towards fall, and as an avid Low Bander, it’s like the run up to Christmas as a child.
I’m so pleased with both the Mod Bob and BT1500A at the base and how well it performs on all low bands.
I’m socializing the Data Dictionary I built at Credit Karma, and teaching Python to my team.
My front yard looks so good after that hard landscaping work this past spring.
So much good stuff, who has time for politicians?
Posted on July 16, 2017
As expected, even though the variable capacitor was a massive Palstar model, a roller inductor has more friction, hence requires more torque.
When I spun it as fast as I could it drew just under 1 amp. That’s very reasonable. One BIG issue is that with “direct drive”, the set screws would unloosen – this is because the shafts of the stepper are stainless steel and there is rattle when you microstep.
Now I understand why Palstar and others use belt driven auto tuners with these large components!
Posted on July 16, 2017
There is more than enough torque for the large Palstar variable capacitor. There was little extra power drawn, but not much.
I’ll try the roller inductor later today.
Posted on July 16, 2017
VOACAP Online with its new grey line time mapping. This the time I worked Manuel this morning.
A year ago I worked LU for the first time on Top Band. I ended up working 5 new one’s between June 21 and September 21, so it was a good summer. I had been working on 160M RX antenna systems, and am now 100% set antenna wise for as long as I am at this QTH. I just worked LU5OM and it took some effort – I am sure I was hearing him better than he heard me.
So far this summer, I’ve worked one new one on Top Band, and I expect maybe a couple more – I’m hoping for V47 and T88, but with lightning to the East of me, I think South America and the Pacific are the best directions.
I still heard LU5OM CQ-ing right at his sunrise. He was still 559 – there was no “enhancement” as there was a few days ago.
The biggest factor on 160M is that there just aren’t many DX stations on this band. Its understandable given how hard it is to make even garden variety DX QSO’s. Trying to be effective on Top Band from a small lot took me years to get it figured out, and I ended up with a pretty unique antenna – one I have never seen mentioned or modeled before.
In fact, no kidding, I’m loving the Mod Bob + u.RAT a lot more than the N6BT DXU-32, which was my previous “favorite” antenna. Cracking the low band nut is a real challenge and a great feat when you finally do.
Posted on July 15, 2017
I’ve been so busy this week getting the u.RAT to work, and work is busy as well that I did not even have time to start playing with the Rigol DS 1024z. I at least have a square wave on it, using a procedure you use to calibrate your probes.
A little tour of the Maker part of the shack.
I have a list of about 12 things I’m doing that are “odds and ends”. I’ll be adding a piece of plexiglass up where you saw those insulators, because it helps with heating and cooling making the shack completely “double paned”. I was able to create a Noobs and Raspberry Pi Jesse Lite boot SD mini card for the Raspberry Pi Zero W, but that little processor died after just a few reboots. I think it’s very important to put these processors in cases right away, else they are susceptible to static and other damaging things. The larger Pi board seems impervious to such problems.
When it isn’t 100 plus degrees out, I will take that old tuner chassis you see above and add rails for the stepper motors. I’m actually more excited about giving presentations and sharing the u.RAT project than retrofitting my Mod Bob remote tuner. Just leaving the BT1500A tuned to 160M is all I need until Bouvet. For me, DXCC just isn’t very exciting any more and adding entities won’t help – its still watching the grass grow.
I am booked to give 4 presentations about it already, and I have floated an idea for a very advanced KPOD at Elecraft and they like it. It’s an extension of my simple project, that’s all I can share right now.
I will be getting the OLED and replacement Raspberry Pi Zero W this week, so will try again.
There are other odds and ends, but the success of getting the u.RAT to work this week was, and I am sure will be a huge milestone moving forward.
A great week and weekend indeed!
Speaking of that, we are half way between kids getting out of school and going back to school. Sort of like summer is half over.
My favorite season is Fall, so, this is cool.