Tag Archives: radio books

Volunteerism

July? Has it really been that long?

Wow, yes it has in fact been that long.

20151104_161606From a building stand point… nothing new has been going on. I am still working on the Beach 40 and the Bitx 20. The Beach 40 still needs the audio section rebuilt and the Bitx20 needs some troubleshooting . I don’t have the facilities to put up a 20 or 40 meter antenna and since both radios are QRP(p), a good antenna is vital to making any contacts.

20151121_072647From an operators perspective… ya, nothing going on there ether. I need to pull down my Frankenstein/Hill Billy mast because we are having our building painted soon. I have plans for a simpler replacement that should work out fine. I’ll post about that if and or when that happens.

From an experimenters view point…  I have been kind of busy lately. Many of the newer radio projects I have been looking at use micro-controllers and embedded Linux systems. All of which I am totally fine with. There are so many other applications besides radio that I can employ these technologies. The only impediment is getting some play time in with these technologies and getting familiar with there capabilities, use, and programming.

arduinoEarlier this year I picked up some Arduino hardware. I haven’t had much time to work with it yet as the Day Job has been keeping me hopping as well as a lot of stuff in the personal life, nothing bad, just a lot of changes and preparations.

Many projects are done with the Arduino and various shields. Some require a little more direction in the form of an embedded system with a true OS. Enter Raspberry Pi and Raspbian.

rpi3bLast week I added a RPi 3B to the hardware pile and began working with it. Along with the Pi I picked up a copy of Exploring Raspberry Pi: Interfacing to the real world with embedded Linux From Wiley written by Derek Molloy.

Linux doesn’t worry me at all. Many moons ago I was a Solaris 7/8 admin as well as a RedHat 7 admin. The problem is that well over a decade has gone by since I actively worked on those systems. I have been in a Windows only environment for so long my Unix brain has turned to mush. So now I’m re-learning the Unix command line and re-acquainting myself with the Linux directory structure along with some all new unique elements of embedded systems and the Raspbian OS in particular.

With all of the projects piling up and now adding a lot of general computer stuff to the pile, Arduino Sketches, Python, C/C++, and picking up where I left off with Perl, it almost feels like I should go back to school and get credit for all of this work. I could pick up a CS degree with everything on my “tech to learn” plate right now. Add in all of the projects and an engineering degree (EE or ME) isn’t far behind. Thoughts for another time.

Radio specific plans are to read and build along with Crystal Sets to Sideband by Frank W. Harris W0IYE, and then get back to Experimental Methods in RF Design and do the same. I don’t expect to do a lot of operating other than 2 meter until we have the facilities to put up a real antenna, and there is no solid timeline for that.

Life outside radio has taken all of my time lately and I am just now slowly getting back to things. Most of it is general electronics/computer experimentation and adding to the knowledge pool right now.

So in conclusion, no I haven’t been busy, I’ve been too busy.

:-/

hamverseryP.S. Today’s post is brought to you by Hamversary. On this day in 2013 I received my license grant about a week after I walked into the Saratoga Fire Station a non-ham. Since then I have worked my way up to Extra Class, begun teaching license preparation classes to prospective hams, and I have been a Volunteer Examiner for 42 exam sessions, most of them at the Saratoga Fire Station.

I have learned so much in so many ways in this short period of time. Thank you Amateur Radio.

73,
~Jon KK6GXG 

Volunteerism

First week of May

First week of may, and ain’t got much to say!

JT65JT9No build projects progressing, not much time OTA, none actually, but I have managed to get some reading in. I picked up a copy of one of the new ARRL books Work The World With JT65 and JT9.

Not bad, a short read, though I must admit, I don’t really see myself using the TJx mode any time soon. It looks like its pretty much a contesting mode. I’m not much interested in contesting until I get more of a station built up, and even then… I dunno.

HighSpeedMultiMediaWith some luck the UPS guy will bring me the also new ARRL book High Speed Multimedia for Amateur Radio book today. I still don’t have a TNC or HF radio up and running, but I do have some spare/old 802.11 units lying around… hmmmmmm…

There could be a project with HSMM on the horizon.

RTTY-PSK32I also have a copy of RTTY/PSK31 for Radio Amateurs 2nd Edition on the way which I think will see more action in the near future than anything else. I have a USB/Serial cable and enough toroids and cabling that I might fourgo the TNC a little longer and build an interface myself just to see if I can get it up and running.

The down side is that I will still only be running whatever digital mode on 2 meter FM rather than SSB, but that will get resolved at a later date.

ARRL-VEC VEIn other news, there is another VE session tomorrow (Saturday, May 7, 2016 08:00-10:00) at the Saratoga Fire Station. This session will be my 30th VE session!

Also this month, Maker Faire is here in San Mateo and I will be working both the morning and afternoon VE sessions at the faire. More info is available on the SF Bay Area Maker Faire VE Session website.

One last thing. I’m not going to post it yet, but since we have been planning on relocating, I worked up a new QSL card to reflect the new location. Once we are confirmed with a new QTH and Grid Location I will post a preview of the new card. Speaking of which, if you would like a QSL from my current QTH email me with your address and I will send one out right away.

Oh, one more thing… I am back to studying for my RADAR add-on to my commercial license.

I guess I have been doing stuff.

73,
~Jon KK6GXG

Amature Radio, Commercial Radio

Not As Planned

Well, it’s the 30th of June and there are a few things that didn’t go as planned.

First and foremost, the Beach 40 is still not ready for prime time. The AF amp is still lagging on power-down and I still haven’t checked the PA. Needless to say, the 40 did not make it on Field Day.

Which leads me to the second no-go for the month, Field Day. Not only didn’t the radio make it on-air for FD, nether did I, on any band or mode.

The day job has been keeping me hopping this month and all my free time has been going to studying for my commercial radio license.  I have been running through Elements 1, 3, & 8 heavily for the last couple weeks. The header for this post is my desk piled up with 30 practice tests, 10 for each element.

My general rule for taking FAA/FCC exams is that when I can take 10 practice tests in a row at 85% or better I’m ready to go for the rel thing. As for Element 1, I am up to 10 in a row at 98% average across the last 10.

Now I am working Element 3 at full speed ahead. The plan is to take the Elements 1 & 3 exams some time over the next 2 weeks. While I’m not pushing it, I want to wrap Element 8 by the end of the month.  3 is the “big one” out of the three with 100 questions from a pool of 600 so it will take the most time to study for.

That’s all for now. Time to get back to the studying.

73,
~Jon KK6GXG

Amature Radio

40 is dead, long live 40!

I had mentioned a little while ago that I was planning to work on a 40 meter receiver followed by a 40 meter transmitter. This is still the plan but there was a snag that I thought was worth mentioning, particularly for those new to Amateur Radio or to homebrew radios.

The 50 Ohm 5Watt dummy load I built last month, and most of the diagnostics tools I have been building recently for that mater, came from the book QRP Basics, second edition by Rev. George Dobbs G3RJV.  Another project in QRP Basics is the 40 meter (7-7.3 MHz) receiver I planned to build. The receiver in the book has some additional modifications to the RF (Radio Frequency) input section, an RF band filter and a modified tuner that replaces the VXO (Variable Crystal Oscillator) with a VFO (Variable Frequency Oscillator.) The VFO has a wider tuning capability, it can tune the entire band rather than 600-700kHz of the band centered on the crystal frequency in a VXO.

First go at the 40
First go at the 40

The diagram made sense, for the most part, and I could see and define the separate sections of the receiver. The challenge was my minimal knowledge of circuit diagnostics.

I got the AF (Audio Frequency) amplifier working fine. Likewise the AF input filter. It was the RF side of the equation that was giving me trouble.

It was clear that I needed to improve my skills in diagnostics so I picked up a copy of Experimental Methods in RF Design by Wes Hayward W7ZOI, Rick Campbell KK7B, and Bob Larkin W7PUA, here after referred to as EMRFD, with hopes that it would give me the information I need to better approach the radio build projects I have planned. Just 8 pages into the first chapter and it is making me think and work!

The receiver I originally planned on, and started, was from QRP Basics. A stripped down basic variation of this receiver is the first project in EMRFD starting on page 1.7. The nice thing is that this design has fewer parts, a VFO that uses a LC (an inductor capacitor network circuit) tuner that gives you the whole band, approximately 6.9MHz to 7.5MHz, best of all the complimentary transmitter is also in the first chapter.

EMRFD makes you think more about what you are doing and requires you to actually learn about each circuit segment. The first chapter outlines a very modular approach, the building blocks of the larger picture but in reverse. Start big with simple broad strokes, then narrow it to more manageable chunks, then further and further as you go. It encourages the start simple philosophy to get it working, then refine individual areas as you go.

The book goes on to give a more in-depth look at specific RF circuits, not a list of projects though, it gives you an idea as to how various RF circuits may be improved or incorporated into a design to improve the over all performance of a project. It seeks to instill an adventurous and experimental approach to RF design. Rather than a “you must” approach it is a “hay, what if” way of looking at overcoming the challenges in RF design work.

QRP Basics is a great book, and it covers homebrew radio, but more as a kit builder and operators guide rather than a circuit designers/builders guide which is what I am really looking for right now. I don’t see myself getting an electrical engineering degree, but I do need to up my game in RF circuits and basic electronics knowledge, big time.

Second go at the 40
Second go at the 40. Parts poked into an anti-stat mat grouped by receiver segment, RF to the left and AF to the right. Look at those sexy toroids!

About the title of this entry… Yesterday I completely disassembled the receiver I started two weeks ago and restocked all the parts.  The 40 is dead. Today I poured over the schematic of the EMRFD design and began picking the parts and planning the layout. Long live the 40!

While part of the goal of EMRFD is to use whatever parts you have lying around, I was going to have to make some weird choices in parallel and series multi-value/component clusters and I am not yet up to the challenge of re-designing things like LC tuning circuits so it was also shopping list time today as well. With a bit-O-luck HSC will have the variable capacitors, resistors, and jacks I need finish this project quickly.

My neatnic brain is not ready to go with “ugly” construction so my boards, at least for now, will be done on perf-board.  I know “ugly” is a perfectly acceptable prototype process, and has benefits in VHF/UHF/SHF frequency applications, but I am working in HF so a little attention to not building in inductive ground planes should be fine. My aversion to “ugly” includes using two 100 ohm resistors in series when I don’t have a 200 ohm resistor. I’m sure I will get over this affliction at some point, I’m just not there yet. In the mean time I will spend a little more time on the layout phase.

Until tomorrow the 40 is on hold. The plan is to have it up and running before April. I have a lot of projects to do this year. 😉

73,
~KK6GXG

ETA: 2015-04-03 The new project page for the EMRFD 40 meter receiver is here.

Flickr photo set for the 40 meter receiver

My first homebrew toroid inductor. Aint she purdy?
My first homebrew toroid inductor. Aint she purdy?