Tag Archives: Amateur Radio

Hams, Kits, Morse Code, News, QRP Radios

Adding CW mode to the EA3GCY DB4020 Dual-band 40 and 20M QRP Transceiver Kit (Part 2)

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Many thanks to SWLing Post contributor, Frank (ON6UU), who shares the following guest post which expands upon his previous DB4020 article:

The EA3GCY DB4020 transceiver now has CW mode

by Frank Lagaet (ON6UU)

After telling you all about the DB4020 SSB build I’m here with the CW part of the kit,  let’s say this is part 2.  At a certain moment Javier let me know the CW interface kit was ready for shipment and some week later it was delivered to my QTH.

Again, a well packed kit arrived in a brown envelope, components and boards well packed in bubblewrap.  I found even a board I did not expect which can hold a push button,  a switch and the connector for your morse key.  Javier thinks of everything it seems!

Unpacking the bubblewrap gave me this result,  all components in 2 bags.  In the bigger bag another 2 bags with 2 printboards,  one for the CW interface,  one for the CW filter.  Great !!  Checking the material bill resulted in all components there,  another thumbs up.

I started, of course, immediately building it because I wanted CW in the transceiver as soon as possible.  I don’t do much in SSB mode anymore and I already started missing CW on the DB4020,  so I started my KX3 to listen to while I was populating the boards.  I never thought CW was going to have this impact on me! …. ..

I started building the CW interface,  again starting with all small items.  I soon saw that the 2 relays which need to be soldered in were ideal to protect all components when the board is upside down, so I soldered them in very quickly.  I then soldered in all other components ending with the elco’s.

Next phase was the CW filter.  This board is small and came together in a blink of an eye, no problems there, the long legs of the 3 and 4 pin headers went in last.

The following day, I made all wire connections and soldered a 13pin connector,  leaving one pin out since I want to have the option to choose the width of the CW signal I’m listening to.  By cutting the FL CW + pin and adding an additional switch, I have now 500Hz or 2400Hz.  Great option, for very little effort and simple.  Another thumbs up here.

Now it was simply a matter of inserting the sub boards in the main board and all should be working.  And it did!  Hurray!  The 500Hz filter works perfectly,  filtering away all above or below stations nearby my operating frequency.

This is the result of the soldering work,  2 small boards which need to be inserted in the main board:

The CW interface still needs the 13pin header of which I cut one pin and mounted a switch to have the 2400Hz width.

The IC you see in the middle of the CW interface is the KB2 keyer which gives you several functions like 4 memories and beacon mode.  The 4 potmeters are used to set the level on 40 and 20 meters,  to set the delay between TX and RX switchover and to set side tone monitor level.   The keyer also provides functions as keyer mode A or B,  straight key function and can be set for speeds between 1 and 50WPM.   WPM speed can be set in 2 different ways.  Handy!

Here a picture of the CW filter inserted on the main DB4020 board.

The CW interface is inserted at the side of the main board,  notice the 2 wires which go to the switch to allow switch-over between 500 and 2400Hz.

(Wiring still needs to be cleaned up in this picture.)

Finally, the result:  a good working multimode QRP transceiver with 2 bands.  It should be possible to make close to medium range with it as well as DX,  even with QRP power.

And while I was building I also made a new key for this radio,  it is made out of a relay and cost nearly nothing,  looks good doesn’t it ?  hihi.

Homebrew key

The key, when in practiced hands (fingers hi), can do 50 WPM without a problem. My friend HA3HK does without blinking an eye at 40WPM with this kind of key and tells me that he can go faster if needed.  Me? I’m going it a bit slower.

Battery pack

As this radio is only using little power (0.4A in RX,  1 to 2A in TX depending the power you set it) I thought,  let’s make a battery pack for the radio.

The first plan was installing it in the box.  I did not do that because the batterypack is also powerful enough to feed my KX2 and other QRP transceivers. Since I can use it with all of them, a loose battery works out better for me.

I started with an old laptop which had a broken screen and some other malfunctions,  but still had a good battery,  although I needed the battery connector of course.  A piece of wood to mount the connector on was my next goal.  And since I still have another laptop using the same batteries, I can charge the battery without problems.  Simple, but good and it weighs much less than a gel cell battery.

The battery provides me with 12.5V and some 5Ah.  Enough to last for hours on RX and for sure good enough to activate 2 SOTA sites in one day.   It doesn’t look great but works great– that is what matters and to test it was more then good.  Next will be getting the battery pack in a nice box.  Better to re-use stuff than throwing it away I’m thinking.

I need to do something about the cover of the OLED display,  there is still some work there to make it look nicer.

Some video can be seen on YouTube :

Finallym I’d like to thank you all for reading my articles about the DB4020. I had big fun soldering, tinkering with the box, making the key, and batteryholder/batterypack.  My Hungarian friend HA3HK told me it looks a bit like a spy radio. …. ..

I also include one more time the link where you’ll find this kit :

https://www.qrphamradiokits.com/

73 TU ee

Frank

ON6UU

Thank you so much, Frank. No doubt, you had a lot of fun putting this excellent little kit together.

Implementing a filter switch was a fantastic idea and, obviously, not terribly difficult to do.

Based on the videos, the DB4020 has a low noise floor and very good receiver characteristics. I’m impressed that the CW portion of the radios has so many features as well, such as a memory keyer and beacon mode.

I also love how you reused that 5Ah laptop battery! I think that could almost give you a full day of SOTA activations at those consumption levels!

Thanks again for sharing this with us, Frank! We look forward to your future articles!

Articles, Hams, News

On The Air: ARRL’s excellent magazine for newcomers…only available behind their paywall

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Cover of the new “On The Air” e-magazine from the ARRL

[Please note: this is a cross-post from our sister site, the SWLing Post.]

Today, the ARRL released their new electronic magazine for ham radio newcomers: On The Air.

The ARRL describes On The Air‘s mission:

“On the Air magazine is the newest ARRL member benefit to help new licensees and beginner-to-intermediate radio communicators navigate the world of amateur radio. Delivered six times a year, the magazine will present articles, how-to’s, and tips for selecting equipment, building projects, getting involved in emergency communication as well as spotlighting the experiences of people using radio to serve their communities, and those using it for enjoyment.”

I checked out On The Air and was quite pleased with the scope of the magazine. The first issue covers topics such as: understanding the ionosphere, choosing your first radio, building simple antennas, and much more. I love the fact that the articles are written with newcomers in mind, too; less technical jargon and more explanations.

I mentioned in a previous post that I’ve been teaching a ham radio class to a group of high school students. Most of the students have now acquired their Technician licenses, and we’re even plotting a General class course for the fall.

Last month, I shared some copies of QST (the ARRL monthly member magazine) with my students. While they enjoyed looking through the pages of QST, many told me they simply didn’t understand the articles yet…There’s just not a lot inside a QST issue to grab the attention of a fifteen or sixteen year old who’s just gotten her ticket. Understandable.

Then, I learned about On The Air from a friend with the ARRL.  I was so glad to hear that the League was finally making a bi-monthly magazine aimed squarely at newcomers! I was also pleased it was an e-publication, because it will be that much easier to share with my class and propagate to prospective students.

But today, I discovered, to my dismay, that other than the premier issue, On The Air is for ARRL members only. Here’s a screen grab from the website:

But…”for members only”––?

Alas, in limiting access, the ARRL has essentially insured that most of their target audience won’t ever have the opportunity to read On The Air, and thus they’ve crippled the best ARRL recruitment tool I’ve ever seen. 

What a shame.

I’ve contacted my ARRL representative and asked that they reconsider the decision to hide this brilliant magazine behind a membership paywall. I’m pretty sure that ad revenue and membership fees could readily cover the cost of publishing this electronic edition. After all, On The Air could lead to a lot more ARRL members! And, indeed, I hope it will.

If you feel as I do, please contact your ARRL Section manager. It may be that those making the decisions are, in this case, a little out of touch with the future of amateur radio.

Update – To be clear about this post: I’m not implying anything bad about the ARRL here, I just think it’s a lost opportunity if they keep future editions of On The Air behind the member pay wall. I imagine that ad revenue alone could more than support this niche publication if they simply release it as a free PDF. The real benefit, though, could be an increase in ARRL membership as On The Air readers get a taste of what the League could offer! In other words: this is an opportunity!

What do you think? Should On The Air be free to anyone interested in amateur radio, or for members only? Please comment!

Grab And Go, News, Portable, QRPers

Scott’s Elecraft KX3 Go-Box

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[Note: this article was originally posted on my shortwave radio blog, The SWLing Post.]

Many thanks to Scott (AK5SD) who shares the following photos and bill of materials for his custom Elecraft KX3 go-box:

IMG_0531 IMG_0534

IMG_0532 IMG_0535 IMG_0537 IMG_0536

Bill of materials

The panel was custom laser cut by Front Panel Express. I have the CAD
file and I’m willing to share it with anyone who wants to reproduce my effort.

Amazon.com
Case B&W Type 1000 Outdoor Case with SI Foam
You won’t use the foam, so you can buy the version without it if you can find it cheaper.

Battery Anker Astro Pro2 20000mAh Multi-Voltage (5V 12V 16V 19V)
Portable Charger External Battery Power Bank
Avoid look alike batteries and the next generation model from Anker. The newer Anker
battery is only capable of delivering 1.5A from the 12V supply. Two look alike batteries
I tried did not have the auto-off feature that the Anker does.

Vetco.net
ACC2 and I/Q Jacks 2 x 2.5mm Stereo Jack Panel Mount (PH-666J-B)
Phone, Key, and ACC1 3 x 3.5mm Stereo Jack Panel Mount (High Quality) (PH-504KB)
Mic Jack 1 x 3.5mm 4 Conductor Jack Panel Mount (PH-70-088B)
12V IN and CHG IN 2 x 2.1mm DC Power Panel Mount Jack (PH-2112)
12V OUT 1 x 2.5mm DC Power Panel Mount Jack (PH-2512)

You also need plugs and wire for interconnects. I bought some 2.5mm (CES-11-5502)
and 3.5mm (PH-44-468 for stereo, PH-44-470 for 4-conductor) audio cables with right
angle plugs and just cut them to use for the signal lines going to the KX3. I did the same
thing for the 2.5mm (PH-TC250) and 2.1mm (PH-TC210) power cables. A couple of
caveats are in order. The Phone, Key, and ACC1 interconnects require low profile
right angle connectors. The cables I listed above won’t work. Vetco part number
VUPN10338 will work. The power cables I’ve listed above use 24 gauge wire. This
is a little light, but the runs are small so I think it is OK. You can use higher gauge
cables if you can find a source.

USBfirewire.com
USB OUT USB 2.0 Right Angle Extension Cable (RR-AAR04P-20G)

Digikey.com
L Brackets 8 x Bracket Rt Ang Mount 4-40 Steel (612K-ND)
These L brackets are used to mount the KX3 to the panel and the panel to the case.
For mounting the KX3, I use a little piece of stick on felt on the bracket to protect the
KX3’s cabinet from damage. Replace the KX3’s screws with #4-40 Thread Size, 1/4”
Length Steel Pan Head Machine Screw, Black Oxide Finish (see below). For the panel
mounting, use #6-32 Thread Size, 3/16” Length self tapping sheet metal screw. You
may need to cut the tip off in order to not puncture the outside of the case.

RG316 BNC Male Angle to BNC Female SM Bulkhead Coaxial RF Pigtail Cable (6”)
This is not the original interconnect I used for connecting the KX3’s antenna output to
the panel. However, I think it is a better option for new designs. The caveat is that you
will need to verify the hole in the panel matches the bulkhead connector on this cable.
There will be a little loop in the cable when you are done, but that is fine.

Micrfasteners.com
Screws for Sound Card 2 x FMSP2510 – M 2.5 x .45 x 10mm
Screws for KX3 Bracket Mount 4 x MSPPK0404 – 4-40 x 1/4
Screws for Countersunk Panel Holes 8 x FMPPK0403 – 4-40 x 3/16
Screws for USB Connector *** 2 x FMPPK0406 – 4-40 x 3/8

I’m pretty sure these are the right length for the USB connector. I am doing it from memory.

Amazon.com or eBay.com
Soundmatters foxL DASH A Wireless Bluetooth Soundbar (OPTIONAL)

Sonoma Wire Works GJ2USB GuitarJack 2 USB Portable Audio Interface (OPTIONAL)
(Make sure you get the USB model, not the 30-pin model.)

This is optional if you want a built-in sound card interface for a waterfall display using iSDR. Make sure to eliminate the holes in the upper left corner of the panel if you are not installing. You will also need 2.5mm x 10mm screws to mount this to the bottom of the panel (see below).

bhi Compact In-Line Noise Eliminating Module (OPTIONAL)

In my opinion, the KX3’s noise reduction is totally ineffective for SSB communications. This external noise reducing DSP is one solution, albeit an expensive one, to that problem. It is only for SSB, not CW or digital modes. It is also available from GAP Antenna Products.

IMG_0530

Scott: you have done a beautiful job here and have spared no expense to make a wonderfully-engineered and rugged go-box. No doubt, you’re ready to take your KX3 to the field and enjoy world-class performance on a moment’s notice. 

Though I’ve never used them personally, I’ve noticed others who have taken advantage of the Front Panel Express engraving service–certainly makes for a polished and professional front panel.

Again, many thanks for not only sharing your photos, but also your bill of materials which will make it much easier for others to draw inspiration from your design!

AK5SD_QSL_Card

Speaking of designs, when I looked up Scott on QRZ.com, I noticed that he also sports a QSL card (above) designed by my good friend, Jeff Murray (K1NSS). Obviously, Scott is a man with good taste!

News, Product Announcements

Flex-Radio introduces the Flex 6000 “game changer” and takes pre-orders at the Hamvention

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Today, at the Dayton Hamvention, Flex-Radio Systems will introduce their newest transceiver, the Flex 6000.

I have read through the preliminary specs and it does promise to be a game changer as they implied in earlier teaser ads.

From their product brochure:

Imagine SmartSDR™

With the FLEX-6000 Signature Series radios, FlexRadio brings a wealth of new capabilities to the amateur including direct digital reception, transmission and networking. At the core of all these new capabilities is SmartSDR. SmartSDR organizes all of the signal processing power in the FLEX-6000 Signature Series radios into an advanced reusable framework. First, the RF subsystems in the FLEX-6000 are virtualized as reusable hardware blocks or Signal Capture Units (SCU) with specific capabilities. SmartSDR understands the capabilities of each SCU and how to harness its power.

As data from the SCUs enters the Field Programmable Gate Array (FPGA) at a combined rate of over 7.8Gbps, SmartSDR performs advanced Digital Signal Processing (DSP) on the data, splitting it into individual Panadapters and Slice Receivers. Panadapters are visual displays of the RF spectrum akin to a spectrum analyzer, but with more capabilities for the amateur. Slice Receivers are dynamically allocated full performance receivers that can be directed to the speaker or headphones for listening, or can be streamed as digitized RF to external digital applications.

Panadapters and Slice Receivers can be created and destroyed atwill. What distinguishes SmartSDR is the simplification of theseadvanced concepts into an elegant graphical user interface (GUI) that places you in complete control. Want to create an additional Panadapter to watch for possible 10m band openings?

No problem, simply click to add the Panadapter and SmartSDR directs everything from the advanced signal processing software down to the filters in the SCU to form an optimized receiver. Want to decode all of the CW signals on 40m while working DX on 20m? It’s just a few clicks away. In the future, remote FLEX-6000 Signature Series radios will be equal partners in the SmartSDR ecosystem. Imagine the capabilities: Want to add two remote receivers so you never miss another check-in as Net Control? Just click to add and combine them.

The brochure goes into great detail about the Flex 6000’s features. Its networking abilities, multiple receivers and even frequency lock that is tied into the GPS system will make this SDR stand out from the crowd.

Pricing?

Prices vary from $3999 for the Flex-6500 to $6999 for the Flex-6700. FlexRadio is taking deposits on pre-orders.

As I head out the door for Dayton, stay tuned. We will post other updates and product announcements throughout the day as time permits. In the meantime, click here to download the Flex 6000 series brochure. I will tag any other notable Flex announcement with: FlexRadio

News, Product Announcements

FlexRadio Systems announces a “game changer”

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This year at the 2012 Dayton Hamvention, FlexRadio Systems will be joining the line-up of manufacturers introducing new products.  On the FlexRadio front page, they’ve posted the following graphics along with the promise of more to come.  It’s a Dayton teaser, but I will be posting updates with firm facts as they become available. Follow our tag FlexRadio for more…

Events, Portable, QRP

The ultimate Field Day tent?

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The 2 kW "Power Shade" is the right size to cover a full-size military tent.

Power Film Inc. is a developer and manufacturer of thin, flexible solar modules.  The company designs, manufactures and retails their products in Ames, Iowa–a quality made-in-USA product.

Last year, at the Dayton Hamvention, PFI’s booth was very popular. Why? Their sale of small, rollable and foldable solar panels, absolutely perfect for field use, drew crowds of hams, DXers, campers, and/or frequent travelers.  Needless to say, sales were brisk.

While browsing their website recently (just for fun), I came across their PowerShade™ Solar Field Shelters. They’re available in 1 kilowatt and 2 kilowatt versions at 15.4 V or 30.8 V.  Wow…

This paneled tent is primarily focused at the military market.  Perhaps exclusively.  And I readily admit, it would be overkill for QRPers, even for a multi-op QRP Field Day.  After all, aren’t we about “less is more”–?

But is it wrong for me to fantasize about this wonderful 2 kW creation? A tent-topper that sucks in Sol’s readily-available energy and, with the assistance of a battery bank, produces enough juice to fuel several QRP rigs?

I dunno.  I’m too busy fantasizing to care…!