sBITX V3 Board Review

 A few months back Ashhar Farhan VU2ESE, the father of the BITX series of QRP transceivers came out with the latest edition of that line the sBITX. Once I checked out the copious number of attributes of this little, I immediately realized that this is the HF Transceiver that I have been waiting for. It first came out as the sBITX D.E. (Developers Edition) this edition was to help iron out all of the little problems that come with launching a new product. 

The sBITX DE may have been mainly for ironing out problematic issues, but it proved to be capable of paving the road for the sBITX series. The future and pretty much the present of HF transceivers is SDR- Software Defined Radio. An SDR is in layman's terms, where many functions of transceivers is performed by software instead of traditional electronic components. This allows the physical size of the transceiver to remain small and at the same time expanding its features. What Farhan did with the sBITX DE was genius. He took a relativity cheap (at the time) single board computer the Raspberry Pi 4 and incorporated it into a custom built 40-watt HF Transceiver. He then made the transceiver, and 

Raspberry Pi OS open source and made everything freely available for anyone to download the software and hack it and change it in any way that they see fit.  

The sBITX DE covered the 80, 40, 30, 20, 17, 15, 12 and 10 meter bands. It was about the size of a bread toaster. It incorporated a Raspberry Pi 4 (2 gb) and a 7 inch Raspberry Pi touch screen. By having the Raspberry Pi fully incorporated into the system, a whole new plethora of features that are not even seen it transceivers costing ten times as much. 

Digital modes has been a large part of the hobby for decades. Usually you need to have an HF transceiver, a computer and some sort of interface that connects the transceiver to the computer. On top of that you need all of the cables that come with the computer, all of the cables that come with the transceiver and the cables required to connect it all together. The sBITX gets rid of most of that mess. You need a power cable and a antenna coax. That's it. Yeah a keyboard and mouse are great additions to the sBITX (does your expensive HF radio use a keyboard and mouse?) but with the Raspberry Pi, those can be wireless. So without any extra devices, cables etc, the sBITX allows you to operate on most if not all digital modes. To help you keep track of all of the QSO's that you will have with this rig a logbook is also incorporated into the system. In some modes it will do all of the logging for you on its own! As we all know, we like to brag about getting some rare DX in your logbook. A lot of the time your buddies will just have to take your word for it. The sBITX now allow you to back up your bragging with the ability to record that QSO and play it back to your envious friends. 

One of the sBITX features that i really love is CW. It is well known that I have a host of medical problems. Some of those problems are neurological in nature. These neurological issues keep me from sending CW via key, paddle, bug and most other devices. I can type decent enough though. There are a few ways to send CW via keyboard. Usually in the form of an expensive keyer that has a keyboard feature as an afterthought. The sBITX really makes my heart thump with its options at sending CW. You can send with a straight key, a bug some paddles, and of the traditional stuff. Also you can have a keyboard on the 7" touch screen where you can send by using the on screen keyboard. As mentioned earlier you can use a wireless keyboard and mouse with the sBITX. So of course the coolest option is you can send CW with the wireless keyboard. The CW signal is decoded on the screen as a back up to you decoding it yourself. 

The first edition for public sale was the sBITX V2. This offered all of the features of the DE edition but the depth of the enclosure was cut down by more than half. The new version was about the size of the ARRL Handbook This made it much more friendly for POTA, SOTA and other portable activities. 

You can pack up the sBITX, a battery and antenna and get out of the shack and go out to a local park and get on the air. You wont need any extra parts like a computer of fancy keyer to show all of the passer by how cool amateur radio is. Also you can use your cell phone as a hotspot so you can use THIS HF radio to catch up on Farhan's latest YouTube video or you can cruise on over to the BITX 20 io group to ask any question you want about any of the BITX radios. The sBITX comes pre loaded with the Libre Office suite of software, so when the bands are dead you can make a antenna measuring spreadsheet on LibreOffice Calc or you can use LibreOffice Writer to write your next best selling novel. Can you write a book on your two thousand radio appliance? Didn't think so. 

The latest edition is the sBITX V3. This is the one that I am blessed to have. I have the board only version where I had to supply the Raspberry Pi, 7" touch display, speaker and microphone. 

The V3 has a new gui (Graphic User Interface) however the V3 operating system and sBITX software will work on the DE and V2 versions. Instead of transmitting 40 watts the V3 has a more respectable (to me at least) 20 watts. 

Now I have put my V3 through some use and racked up a few new countries. Here is my setup, but your mileage may vary. 

• sBITX V3 transceiver board only (I really need to figure out an enclosure for it before something gets shorted out.) 
• Raspberry Pi 4 (4 GB RAM) 
• ATU-100 EXT Automatic Antenna Tuner, I really do not need this (see antenna below). I'm mainly using it as a power/ swr meter which again is not needed at when transmitting the sBITX displays the transmitting power and the SWR. 
• 20 Meter homebrew Inverted V dipole broadside east-west. The feed point is 32' above the ground. I have it tuned to 1.0:1 - 1.1:1 SWR on the CW and Digital portions of the band (14.000-14.200 MHz).

I do not have a dedicated room for my shack. My house is fairly small and there are four humans and a cat that call this place home. My "shack" is one wall on the side of my bedroom that I share with my beautiful XYL. We have been married since June 1997. To have a long lasting happy marriage both parties must be willing to compromise. Saying that me and my wife have two different sleeping patterns. My wife likes to sleep in late and decades of work tuned me into getting up a couple of hours before the Sun. So I make an extra effort at being quite so my wife can sleep. To make this even more challenging, I'm mostly deaf and I live in my bed, so getting up and going to another room is generally not an option. So I tend to lean towards the quieter modes like CW and digital modes there I can wear head phones. Typically we still have to put up with the sound of a fan keeping the finals cool on the radio and of course the ever present clacking of the relays. Well the sBITX has neither of those. Operation is really quite. You can hear the electricity flowing during transmit but that isn't really loud enough to be a bother. I was having a problem with SWR. The radio would dial down the power to one or two watts, the SWR was being displayed at 25:1 and higher. Every time I would transmit the computer monitor that I was using for a display for the sBITX would shut off. It was driving me crazy. The antenna kept measuring a perfect 1:1 SWR. After several days of looking for the problem (Remember because of my health I could search for just a little bit at a time so what would take a healthy person a few hours took me days) and I finally found the problem as being a loose coax connector. Once I got that tightened up, the sBITX has proved to be better than I even dreamed that it would be. I use a 15" computer monitor instead of the 7" touch screen display. The reason for this is entirely because of my eyesight and has nothing to do with the radio. I'm due for some new eye windows so that problem should go away. I have been mostly on FT8 and I'm not used to having such an awesome waterfall display. I still have a lot to learn about this awesome radio and I bet I'm going to be enjoying the learning process. You can go ahead and view the sBITX as the new radio on the street. To me it the ONLY radio on the street. I plan on pushing this radio to the limit and I'm sure even at a proper QRP level of 5 watts the sBITX is going to make my logbook fatter than my stack of bills. 

Over this winter I plan on having a few more surgeries to get some of my back problems ironed out. I plan on healing up in time for spring. The plan is for me to be able to start riding my recumbent trike again. Since I was last active on my trike Midwest City has built many new miles of bike trails and even a new city park. With the small size of the sBITX V3, I will be able to put it in my trikes saddle bags with a battery and some wire and go back to operating portable. Permanently mounted on my trike is a 23' telescoping fishing pole that is perfect at supporting a wire antenna. I recently was able to get a second matching fishing pole so expect me to add that to the trike to expand my options. I have already added a HT and a small dual band mag mount antenna. This is to let me talk to my friends while riding the trike. Also in the past I would go out and ride and hurt my back or have my blood sugar to drop to dangerous levels and would require someone to come and help me out or bring me to home or the hospital. On my trike I wear a small head set so I only need to press a single button to operate the HT and get into the repeater. I'm lucky that my mother in law and daughter have their radio license and I have many wonderful friends that monitor the repeater just in case for me. 

I plan on sharing my sBITX exploits here on this blog. I have many plans for it in the future. My brother recently moved into a house that is just yards from a state parks that will need to be activated. I have family that live on SOTA Summits that need to be activated. I can't wait to work the world with this little radio, its gonna be fun. So as always, feel free to share any comments or ask any questions in the comments section below. You can be notified of my adventure and any future blog posts simply by subscribing. Please email me (I get lonely) at Aaron@K5ATG.com

Until Next Time 

'72

Aaron K5ATG

Merry Christmas

 Merry Christmas from the K5ATG Amateur Radio Station in Oklahoma City to each and every one of you through out the world. May the Lord bless all of you. 

72

Aaron K5ATG

AR Notebook #1.1 sBITX RFI

 I had my sBITX v3 hooked up to my computer monitor via HDMI - VGA adapter cable. I removed the HDMI - VGA cable and took my computer monitor out of the system. I then hooked up a 7" Raspberry Pi monitor to the sBITX via HDMI Micro to HDMI cable. This worked pretty good, but that isn't surprising since the sBITX is designed with a 7" Raspberry Pi Touch Screen. As mentioned earlier my sBITX v3 is just the bare board model. I have to supply the Raspberry Pi 4, Monitor, and enclosure. At the time of this post the sBITX is still without an enclosure so that could also be a cause of RFI. 

Since my eyesight is really poor it is hard for me to see everything with the 7" monitor. The sBITX gives you so much information on the display that the font becomes really small. If you use the WEB option on the display that helps quite a bit with larger font. The sBITX is open source so I bet that there is a way to design a optional display that cuts down the amount of information displayed on the sBITX screen to make room for a larger font. I should look into that. 

The sBITX gets its brains from the Raspberry Pi 4. In my experience you can operate the RPI4 headless using VNC and other options. I can then use my PC monitor as a display for the sBITX without any cables. That looks like the easiest option at this point. 

Again until next time you are encouraged to leave comments or questions in the comments section below. Also you can email me at Aaron@K5ATG.com

'72

Aaron K5ATG

AR Notebook #1.0 sBITX RFI

 Got my sBITX v3 from HF Signals and set it up to kick the crap out of the F Layers and in true Aaron the Great style, there was no assault on the atmosphere. Actually the atmosphere did not even get bumped. 😢 But hey I tried. First things first, here is my setup:

• Cool I made a dot
• sBITX v3, 20 watt SDR transceiver that is good on 80-10. In my case it is just a populated PCB with a large heat sink. HF Signals are running a little bit behind on the enclosures and they will get one to me when they can. So for now it is all open air. 
• N7DDC ATU-100 Extended Board Antenna Tuer
• Another dot
• Homebrew 40 Meter EFHW
• Just one more dot for the road. 

I have a 15 inch computer monitor hooked up to the Raspberry Pi 4 that make up the smarts for the sBITX v3. I also have a wireless keyboard and mouse hooked up to the sBITX. How many HF radios do you know of  that uses a keyboard and mouse? 

The problem is that when I go to transmit the computer monitor goes black and remains that way until I stop transmitting.Once I stop transmitting the monitor goes back to normal operation. Since the transceiver is not in an metal enclosure I think that may have something to do with the RFI. Since I'm still in bed rest recovering from my surgery, I'm very limited on what I can do. My first step is I will try to put some ferrite beads on the HDMI cable that connects to the HDMI Micro jack on the Raspberry Pi 4 and I have it connected to the display with a HDMI-VGA adapter. Once I do this, I will post the results and try to come up with a plan to go from there if it does not work.

As always feel free to leave a post in the comments any suggestions for this RFI is welcome. You can email me at Aaron@k5atg.com

72

Aaron K5ATG

Sacroiliac Joint Surgery

Here is a little update on my surgery. 

On 07 Dec 2023 I had surgery on my lower back. My sacrum and ilium (as seen in pic below) are no longer properly attached to each other by the sacroiliac joint.  

The sacroiliac joint is normally formed with ligaments and cartilage. In my case the cartilage is completely gone and for several years now the joint has been nothing but bone on bone. To repair the sacroiliac joint they have to put in sacroiliac fusion cages on each side. Last Thursday they did my right side sacroiliac joint. They had planned to use three of the sacroiliac fusion cages but they were able to use just two. 

 Here is a pic of a sacroiliac fusion cage. It is just a large pin that is hallow. I have two of these on my right side. 

I don't know yet if the surgery helped out  or not. I'm still in a hell of a lot of pain. The surgeon told me that B.L.T. was out of the question at least until my two week follow up. That made me want to eat several B.L.T.'s just to show them that eating a bacon sandwich would not destroy my hip. Then they explained that No B.L.T. means No Bending, No Lifting, No Twisting. That is a load off my back because I could really use a sandwich right now. 

After the surgery on Thursday the hospital staff really irritated me. My room was really hot so me and Desi kept asking for a fan and they said that they don't have any. So I was laying there sweating all darn day. Then the night nurse came in and got a fan that was hidden in my rooms closet. That helped out a lot. Then later on another nurse showed us that the rooms heater is actually a heat and air unit. We set the temp down to 58 degrees for a bit and things got a little bit better. 

Then there was the issue with my pain medicine and insulin. I had just had surgery and they would not get me any pain medicine! They would say, "If you are in pain let us know and we will get your pain medicine" I would tell then and they would go off  to get it and we would not see them again. It is like they got distracted and never bothered. Then one they would come back again I tell them that I need pain medicine and they would again go off to get it and never return. 

Also during the surgery they gave me steroids, and this caused my glucose to sky rocket. The glucometers that we were using topped out at 400. So all day Thursday they would not give me any insulin to lower it. All day long my insulin was at least 400. Then Thursday evening a nurse gave me 6 units of the insulin that I normally use 20 units on. 

Once I got home I was able to get back into my routine on insulin and medicine and now I'm starting to feel human. It hurts really bad, I can't put any weight on it. I ended up getting 9 staples so this makes the first time that I got staples. 

So now I'm in bed rest and can't do anything for at least 2 weeks. Once I recover from this surgery then we will get my left side fixed. Until then I have to really take it easy because my hips are kind of lop sided. One side has a strong joint and the other side has nothing there to hold it together. 

Well that is about it, feel free to leave any comments in the comments section below. You can email me at Aaron@K5ATG.com

How Photographs Were Transmitted by Wire

 

This is some pretty cool old school technology. This technique was used in the 1930's to send a photograph using radio waves. Not really sure why they made it so complicated. It would have been a lot easier just to send the picture in a text message lol. Seriously though, this was probably the best technology that they had and we had to go through that to get to where we are today. They were technological pioneers who paved the road to Silicon Valley.

As always feel free to follow and you can leave comments in the comments section below. My email is Aaron@K5ATG.com

'72/73

Aaron K5ATG

Crick Mint 20 a Homebrew Minimalist 20 Meter Transceiver Part I

 As I have said before in previous posts, I'm net to homebrewing. I have started working towards a homebrew sBITX but I feel that radio is much more advanced at what my skill level is. So to build up more experience, and to get a cheap pretty sweet transceiver to boot, I have decided to build a 4SQRP Cricket 20 designed by David Cripe NM0S and Virginia Smith NV5F. 

This transceiver was inspired by the infamous Pixie QRPp minimalist transceiver. (QRP in amateur radio terminology is generally considered to be a radio that is transmitting 10 watts of power for phone modes and 5 watts for CW and digital modes. QRPp is transmitting a power levels that are below 1 watt.) Even though there have been thousands of Pixie's made around the world, a probably logged dozens of contacts. It just did not have that special something to make it worthy enough for the prestigious 4SQRP name. So David NM0S and Virginia NV5F got together and came up with a design that is greatly improved over the humble and overrated Pixie. 

As you can see in the piciture above, the Cricket kits from 4SQRP doesn't have toroids to wind, This is a design feature by David NM0S thus eliminating the need for winding toroids. Another feature with the Cricket kits are  the on board straight key it is all powered by a 9 volt battery. Get a 49:1 UNUN and a 34 foot wire that is tuned to the frequency of your Crickets crystals (14.030 MHz and 14.060 MHz) and you can have a complete station that will easily fit in a pencil box. 

Please visit the 4SQRP Cricket 20 for more information about this wonderful little transceiver. A great read is the Introduction to the Cricket by David NM0S. 

My mission with the 20 Meter Cricket is to homebrew it and also have it fit in an Altoids tin if possible. There are some other changes that I would like to make if possible:

• Remove the on board key. This will save a lot of space in the Altoids tin. Also I prefer to just add a key jack. I have to send CW with a keyboard and I need a jack to plug my keyer in. 
• Increase the transmit power from 0.7 watts to 1 watt,
• Possibly add a small speaker onboard
• Get rid of the 9 volt battery. I would rather set it up to power it with a 12 volt battery so that it is standard across all of my radios. 
• Add transmit and receive LED. Lights are cool. 

One feature that I would like to explore and see if it can be done with my Crick Mint 20. QRPGuys AFP-FSK Digital Transceiver III has an interesting way to make a small QRP radio multi-band. 

They have different modules that plug into the transceiver. Each module has all of the band specific components for each band. You could make a module for each HF band and to change bands you remove the current band module and plug in the band module that you want. This is something that I really would need help with but it would be pretty cool to have a multi-band Cricket.  Let me know what you think in the comments section below. 

That is about all for now. You can follow along this build by following this blog. Another place to follow along is the Crick Mint 20 Thread On the 4SQRP Group thread I will have discussions from other amateur radio operators about any problems or modifications that I make. 

Again if you want to follow this build or any future builds hit the subscribe button. Feel free to leave any comments in the comments section below. If you wish you may email me at Aaron@K5ATG.com

'72

Aaron K5ATG 

Big Brutus Bash 2023

 

Each year in September members of the Four State QRP Group gather near the small town of West Mineral in southeast Kansas. The place of the gathering is the Big Brutus Electric Shovel and Rustic Museum. I can go on and tell you all about Big Brutus but I do not think that I could do a description any better than the Big Brutus website. So through the magic of copy and paste here you go:

THE RICH HISTORY OF BIG BRUTUS

Constructed in 1962 by the Bucyrus Erie Company for the Pittsburg & Midway Coal Mining Company, Big Brutus served as a testament to human ingenuity and hard work. This colossal machine operated for over a decade, dramatically increasing the efficiency of coal mining in the region before retiring in 1974. However, its retirement marked a new beginning. In 1985, it was dedicated as a museum and memorial, signifying its enduring legacy. This dedication recognized Big Brutus as not just a symbol of the past, but as an eternal tribute to the mining heritage of southeast Kansas and to the minors across the nation who toiled to support their families. In September 1987, the American Society of Mechanical Engineers (ASME) designated Big Brutus a regional historic mechanical engineering landmark, the tenth such designation since 1971. Adding to its accolades, Big Brutus was placed on the National Register of Historic Places in 2018, further cementing its significance in American Industrial History. 

This was the very first time that I was able to visit Big Brutus. I would not have been able to go this time if it wasn't for my friend Tim Harpor W5TAH taking me. The drive from McLoud to the Big Brutus site took us about four hours. I wasn't really sure what to expect until we got there and I saw Big Brutus rising 160 feet (48 Meters) above the beautiful southeast Kansas landscape. To say that this electric shovel is big is really just a big understatement.

For scale look to the right of the picture and between the shadow and the digger in the distance. That silhouette that you see is a 6 foot (1.8 meters) tall man. 

The 4 State QRP Group was located under a very nice pavilion not far from the museum or Big Brutus.  There were around 20 people there for the event. Radios that i saw there were the Elecraft KX3, Elecraft K2, uBITX. I saw a 4SQRP radio there but I can't recall which one it was and I forgot to take any pics. My setup was my Elecraft K2 with my homebrew end-fed random wire. 

For me the main attraction was the people. I got to meet people from Kansas, Missouri, Oklahoma, Nebraska and Arkansas. Basically all of  the 4 states that originally made up the 4 State QRP Group plus Nebraska. In the afternoon we were all spoiled by some wonderful bar-b-que. 

This warehouse size room in the picture above is actually inside Big Brutus. In the picture above of the exterior of Big Brutus this area is located in the right side of Big Brutus. Instead of being a factory or warehouse this is inside of a mobile machine that can move under its own power. 

This picture shows Tim W5TAH underneath Big Brutus. On the left side are the tracks. The entire machine has a total of 16 tracks. From looking at them it looks like just one link would be close to a ton. 

This is yours truly setting at the controls. Just the controls at my hands were enough to operate this Latvian. Behind this control room is a break room that is about 15X30. 

Well that is all for now. Please help me support this blog by subscribing to it and sharing. If you have any comments please leave them in the comments section below. You can reach me at Aaron@K5ATG.com

'72

Aaron K5ATG

Happy Birthday Faith

Just wanted to give a shout-out to my daughter Faith K5FTS. Happy 17th Birthday. 

Experimental Methods in RF Design

 My life is not in the best shape at this time. Due to my wretched health, I am confined to bed nearly every hour of the day. There are many days that I feel as if someone in prison has more freedom than me. Prisoners get to go to the yard every now and then. I don't want this to be my life. I won't let it be. Yeah, I am in really bad shape. My back surgeon doesn't want me to get out of bed even to go to the bathroom. Someday I hope that will change. 

My body may have failed me but my brain works nearly as well as a well-oiled engine that's out of gas. I have officially been an amateur radio operator for a decade. It was April 2013 when I got my ticket. It was May 2013 when I got my first QSL card. Yeah sure it was from a FCC Listening Post but I'm still counting it. 

I would really love to expand my horizons into homebrewing my own gear. Yeah I have a homebrew project started with the sBITX. that is because I REALLY  want that radio and I can't afford it, so homebrewing it is the only chance that I will ever have at getting one os to brew my own. So in order to do that, I must learn electronics. I was not born with a golden transistor in my fist. I have absolutely zero experience in electronics. I'm learning on the go. However I have a plan......

I think...

There are two books that have become homebrew Bibles. Those are Sold State Design for the Radio Amateur and Experimental Methods in RF Design. I decided to use that later since I have a paperback copy of it. 

So my plan in learning homebrew electronics is pretty simple. I plan on building as many circuits in EMRFD as I can. By doing this I hope to:

•  Learn enough about electronics that I can possibly help someone in the future.
• Share my builds here on my blog to encourage others to comment and advise me on improving my skill. 
• Pay forward all of the help that so many others have given me over the years.
• Get a follower to my blog lol

So that is my world-changing plan. is to start at the beginning of EMRFD and start screwing up uh ok, building the circuits. I'm gonna do my best to build each circuit to the best of my ability. I would like to say test and explore each circuit but since I don't have much in the way of test equipment, but we will bomb that bridge before we get to it. I'm going to write it up my way. I don't want it to be just another dry blog. I pay for the site domain, and hey, like the call sign says, I am bloody Aaron the Great. 

So if you wish to be entertained by my multitude of mistakes, and let me tell you this the mistake stein will never go dry, so all you have to do is to lay down that clock on the follow button and you will become one of the chosen few. I'm n American and I support freedom of speech so throw down your lines in the comments department. While you are at it sling me an email at Aaron@K5ATG.com

Solder on my friends

'72

Aaron K5ATG