Category Archives: QRP Radios

POTA Field Report: Pairing the Icom IC-705 with the Elecraft T1 and CW Morse Pocket Paddles

The new CW Morse “Pocket Paddle.”

On Wednesday, October, 14 2020, the weather was gorgeous so I decided to make an impromptu POTA activation of Pisgah National Forest and the Pisgah Game Land (K-4510 and K-6937). These sites are the closest to my QTH and only a 15 minute drive (in fact, I can even hike up to the same trail network from my back yard).

My canine companion, Hazel, jumped into the car before I could even invite her to come along.

We drove to the trailhead, parked, and hiked a short distance into one of my favorite spots where it’s relatively flat, with lots of tall trees and almost no foot traffic from other hikers.

This activation gave me an opportunity to use the Icom IC-705 in more of a “backpack” setting since I hiked in with only my pack, Hazel, and my folding three-leg stool. Up to this point, I’d only used the IC-705 on picnic tables and flat surfaces since it can’t easily fit on my clip board like my MTR-3B, KX2, and KX1 can.

The activation also gave me a chance to evaluate a new product sent to me by the CW Morse company: their “Pocket Paddle” designed specifically for portable operations.

After reaching the site, I easily deployed the EFT-MTR antenna using my arborist throw line.

I decided to set up the Icom IC-705 much like I did the lab599 Discover TX-500 when I took it on hikes: mount the radio above the front pocket of my Red Oxx C-Ruck backpack.

The arrangement works quite well–I simply sit on the stool in front of the pack and hold my simple logging notepad and paddles on a clipboard.

While this particular site is great because it’s so accessible to me, the negative is it’s deep down in a valley surrounded by high ridge lines. I feel like this does have some impact on how well my signal travels.

Wednesday, it took nearly 50 minutes to rack up a total of 12 contacts in CW mode.  I never bothered with SSB/phone because this site had no cell phone service and, thus, there was no way to spot myself on the POTA network.

That’s okay, I felt pretty chuffed about racking up 12 contacts with 5 watts and a wire! This is what field radio is all about, in my opinion.

Loving the Elecraft T1

The Elecraft T1 ATU pairs beautifully with the Icom IC-705.

After a little falling out with the mAT-705, I decided I wanted to try other ATUs with the IC-705. I used to own an Elecraft T1 ATU and loved it, but I eventually sold it for a song to a friend since all of my field rigs at that point had internal ATUs.

I reached out to Elecraft and they sent me a T1 on loan to give it a go.  I’d forgotten how much I love this simple, effective ATU.

Even though the EFT-MTR is resonant on 40, 30, and 20 meters, moving to the 30 meter band requires lowering the antenna, pulling off an SMA cap on the coil, then re-hanging it.  Not a big deal at all, really, but it’s so much easier to simply press the tune button on the T1 and have it match 30 meters without going through the normal process.

CW Morse Pocket Paddle

I also thoroughly enjoyed using the CW Morse “Pocket Paddles.” I’m not sure when they’ll be available to purchase (perhaps they are already?) but I can highly recommend them.

The paddle action is field-adjustable and even though there’s an Allen wrench built into the paddle base, the machined screws are easy to twist by hand.

They feel very sturdy, too, much like the other CW Morse paddles and keys I’ve used.

I believe the Pocket Paddles are going to permanently pack with my IC-705!

The Icom IC-705 might be a ‘Holy Grail’ portable QRP SSB transceiver

While visiting my parents this week in the Piedmont of North Carolina, I took some time Monday afternoon to take the new Icom IC-705 to field and activate Lake Norman State Park (K-2740) for the Parks On The Air (POTA) program.

So far, most of my time with the IC-705 has been in CW mode but a number of my readers have been asking about SSB operation and performance.

My goal for this park activation was to give the IC-705 a proper shake-out on SSB.

Set-up

The activation was very much impromptu–I only decided I could fit it into my day an hour before my start time. In addition, while it wasn’t raining per se, there was a very heavy mist/fog that, at times, felt like a light sprinkle/drizzle.

I packed and planned on using my IC-705, mAT-705 external ATU, and Vibroplex End-Fedz EFT-MTR wire antenna.

I had an issue with the mAT-705 ATU (read more here), so opted for my trusty and incredibly capable Emtech ZM-2.

I did begin the activation in CW and quickly racked up a dozen or more contacts in short order after spotting myself. One of the great things about Lake Norman State Park is it’s one of the few locations I activate these days with proper cell phone coverage for mobile internet so that I can update my own activation spots on the POTA site.

I also moved up to 20 meters and switched over to my recently (re)acquired Elecraft KX1 (FYI, I named her “Ruby” so no way will I sell her again).

I quickly snagged two states (Iowa and Kansas) with 1 watt of power from the KX1’s internal AA cells, then 20 meters fell silent, so I moved to 30 meters to work a few more stations.

SSB on 40 meters

I then moved to the 40 meter band and decided to record a quick video after spotting myself on 7197 kHz.  I wasn’t expecting such a productive mini pile-up.

As you can tell from the video, I had my hands full trying to hold my phone/camera, log, and manage the hand mic. Note, too, I prefer not hooking up the speaker portion of the microphone because audio from the IC-705 internal speaker is far superior:

I operated SSB for a good 30 or so minutes and was busy with contacts thanks to all of those excellent POTA hunters.

IC-705 Voice Memory Keyer

Before packing up, I remembered that my buddy Dave had asked me to make a video showing how I use the IC-705’s voice memory keyer, so I moved up to 20 meters (which you’ll see was pretty much dead) and recorded this.

Doh! I had the SSB position in LSB instead of USB! Thanks to one of my YouTube viewers who noticed this. I had been tinkering with mode settings earlier while evaluating the rig. No worries, though, this was more a demo of the memory keyer–check out SSB operation in the video above.

I was actually very relieved 20 meters was dead because I’m terrible at managing a camera, a tablet, and a microphone all at once!

The Icom IC-705 is an SSB champ

Photo taken at South Mountain Game Land last week.

Despite the fact that I was using the default microphone settings and had not even touched the TX EQ or compression, I received no less than three unsolicited compliments about my audio during this activation.  That is probably a personal record.

No doubt, the IC-705 is a very capable rig for QRP SSB where audio quality is essential.

On top of that, the eight voice keyer memories are incredibly useful when activating a park, a summit, or even running a contest where you could truly automate your exchanges.

Have you been using the IC-705 in the field? What are your thoughts? Do you have any questions? Please feel free to comment!

Begali is making an Adventure Key stand and mounting bracket for the Icom IC-705

Many thanks to Ray Novak (N9JA) at Icom America who shares photos of the Begali-05 bracket prototype that is being developed for the Icom IC-705 transceiver.

Those who already own a Begali Adventure key will soon be able to mount it on the IC-705 with the Begali-05 bracket.

Ray notes that this is still an early prototype, so the finished product might look quite a bit different.

He also noted, “The plan is for the Begali-05 to be available at Authorized Icom Amateur Dealers.”

I’m a massive fan of Begali keys. Not only do they make some of the best, highest precision keys in the world, but the Begali family are proper ham radio ambassadors. I love supporting them!

Pietro Begali (I2RTF) winner of the 2019 Hamvention Technical Achievement Award.

I’ll attempt to acquire a Belagi-05 bracket and Adventure Key for review with my IC-705. In truth, though, I’m sure it’ll work beautifully. It’ll be a Begali!

Have you ever regretted selling a radio? I have. More than once.

The Elecraft KX1

I’ve been a ham radio operator since 1997. In the first decade of my amateur radio life, I only owned three HF radios (Icom IC-735, Yaesu FT-817, and a Ten-Tec OMNI VI+).

As I got into writing, blogging, and evaluating/testing radios, that number increased. Quite often, radios are only in my shack for a short period of time as I alpha/beta test and/or review production run units.

I try not to get attached to radios because I know they’re often only temporarily in the shack.

Over the years, there have been a few radios I’ve sold for…let’s say “pragmatic” reasons. It’s very rare that I purchase a radio with the intention of keeping it only to find that I want to sell it shortly thereafter. More likely than not, I sell because the radio is redundant (how many field radios does one need–?) or because I’m raising money to make a larger purchase.

Here’s a short list of transceivers I regret selling/trading:

Elecraft KX1

I sold my Elecraft KX1 in 2016 in order to help purchase my Elecraft KX2. It was a solid decision. The KX2 has become my favorite field radio (here’s my review) and was SO much more versatile than the KX1. Still: I really miss the KX1. I loved how bare-bones it was, I loved the top-mounted controls and the fact I often operated it while simply holding it in my hands. The controls were super easy to use even with gloves on in the winter. Plus, it was “cute” in a boxy Elecraft sort of way. If I ever find a deal on another one, I might grab it!

Elecraft K2

I’ve owned both the Elecraft K2/10 and K2/100. Funny story: I acquired a K2/10 in 2008 or so and absolutely loved the radio. After I purchased my KX3 in 2013, however, it was rarely used and sat on my shelf as a “back-up” radio. Eventually, I decided to sell it and did so with ease. Within a week of selling it, a local ham posted on our club email list that he was selling a K2/100 in an SK sale. He wasn’t sure of all of the upgrades, but knew it was a K2/100. The price was very low, but there were no takers after a few days, so I bought it. I used the K2/100 for a few years and it served as a back-up 100 watt radio. I eventually sold it, though, to purchase a KXPA100 used. Now, of course, I do miss that radio. In truth, I’ll likely never purchase one again, because I own so many other transceivers–and the KXPA100 is truly a genius compliment to the KX2 and KX3–but I do have an affinity for that fine rig.

Index Labs QRP++

QRP+ ad from the Dec 1995 issue of QST. Source: WD8RIF

My buddy Eric (WD8RIF) is to blame for this radio. He owned an Index Labs QRP+ for years. He loved operating it in the field and at home. It was the first QRP radio I ever saw in action (at this particular field event). More than 10 years ago, I happened upon a great deal on a QRP++ and instantly bought it. It was SO much fun to operate—super simple, yet had pretty much every feature you’d want in a basic transceiver. I sold it because, frankly, performance was sub-par especially if you ever planned to use it in an RF-dense environment. The receiver front end would simply fall apart, for example, during contests or events like Field Day. Otherwise, it was a pretty sensitive radio. It was incredibly portable and had that awfully “cute” cube form factor. Another fear I had was availability of replacement parts. Index Labs was no longer in business and there were quite a few obsolete parts in the radio. Perhaps it’s a stretch to say I “regret” selling it because, in truth I don’t. But when I see them at hamfests, I’m still tempted to grab one if for no other reasons than nostalgia.

Yaesu FT-817

I purchased an ‘817 shortly after they were introduced in…what…2000? At the time, there wasn’t a radio like it on the market: it was the most compact full-featured HF/VHF/UHF radio in the amateur radio world. Back then, I was living in the UK and travelling all over Europe. I purchased the FT-817 with the idea that I could play radio while, say, working in Hagen, Munich, Chartres, Berlin, Torino, Pescara, or any of the other fabulous sites I regularly visited. I did pack the FT-817 on a number of occasions but since I’m a one-bag traveller, it was scrutinized to some degree at most airports—especially post-9/11. Also, my first production run model blew its finals within the first two years of ownership (a common problem that was addressed by Yaesu shortly after that production run).

I had the finals replaced by Burghardt Amateur Center but rarely used the FT-817 after that. Truth was, I found the radio’s front panel to be too compact and the embedded menus really frustrated me. But back then, I wasn’t as much of a field op as I am now and I could really appreciate a compact, affordable radio that also sports VHF/UHF operation—especially for SOTA activations. Plus, few transceivers have enjoyed a product life like the FT-817/818 which is now pushing 20 years on the market. While the 817/818 lacks a number of features I’ve grown to love (like memory keying) I do believe I may purchase an FT-818 next time they go on sale. In the end, I miss the rig.

How about you? Any regrets?

Please feel free to comment with any radios you regret selling, trading, or giving away over the years and tell us why you miss it! Inquiring minds want to know!

Operating the Icom IC-705 QRP transceiver in CW with full break-in QSK

Readers have been asking me about operating the new Icom IC-705 in CW; specifically if the T/R relay is noisy and how full break-in QSK sounds.

Here’s a quick video that should answer a few of those questions:

I made this video yesterday while testing the new mAT-705 ATU.

Please comment if you have other IC-705 questions.

642 Miles Per Watt with the new Icom IC-705 QRP transceiver

Thursday, I set out to test how long the Icom IC-705 could operate during a Parks On The Air (POTA) activation with one fully-charged Icom BP-272 Li-ion battery pack. This, following my listening endurance test.

I knew conditions were pretty terrible Thursday in terms of propagation, but that didn’t really matter. I intended to call “CQ POTA” in CW until the ‘705 finally shut down due to low voltage. In my head, I imagined this wouldn’t take much longer than 1.5 to 2 hours and during that time, despite propagation, surely I’d work 10 stations to validate the activation, right–?

Sandy Mush Game Lands (K-6949)

I picked Sandy Mush Game Lands as my test site. Since I’d been there before, I knew there were ample trees to hang the Vibroplex EFT-MTR end-fed antenna, and I knew I’d likely be the only one in the parking area as this site is secluded and this was not a designated hunting day.

The Vibroplex/End-Fedz EFT-MTR antenna

Setup at the site was pretty straight-forward. I quickly deployed the EFT-MTR antenna–using my arborist throw line–in a “V” shape hanging over a high tree branch.

I picked the EFT-MTR because it’s resonant on my three favorite POTA bands: 40, 30, and 20 meters. Note that the IC-705 does not have an internal ATU.

Although I have an mAT-705 external ATU on loan to test, I didn’t take it to this first activation–I wanted to keep the set up simple for testing battery endurance.

On the Air

I started calling CQ at 16:30 UTC on the 40 meter band and set the IC-705 to beacon mode call “CQ POTA K4SWL.” No replies for 10 minutes. At that point, I discovered the POTA spots website was down for a scheduled upgrade (I have impeccable timing!), so I posted my spot on the POTA Facebook page.

Then my buddy Mike (K8RAT) sent a text message stating that the Reverse Beacon Network (RBN) had spotted me, but with a very low signal report. Hmmm….why would that be?

Turns out, I still had the IC-705 power level set to “0” watts (this story might sound familiar). Doh!

Note to IC-705 owners: zero watts is not zero watts!

I turned up the power to 5 watts (the max the IC-705 will achieve on a 7.4V battery pack) and was greeted by an instant CW pile-up.

What a blast! I started on 40 meters in CW, but eventually worked both 40 and 20 meters in SSB and CW. I then lowered the antenna, removed the SMA cap on the EFT-MTR coil, and worked 30 meters CW for the remainder of my time.

I logged my first contact at 16:28, my last at 18:18 UTC. So 1 hour 50 minutes of near constant operating.

Remaining battery capacity after 1:50 of operating.

The IC-705 battery pack was still going strong and had about 40% capacity left, but I simply ran out of time as I needed to run an errand in town, so had to shut down the radio and pack up.

I must admit: the IC-705 is doing a much better job managing battery usage than I would have expected. I’m guessing I could have operated for 3 hours or so at 5 watts without needing to recharge the BP-272 1880 mAh Li-ion battery pack.

I do believe I’ll invest in the larger BP-307 battery pack which has a capacity of 3100 mAh. It’s a pricey battery, though, at $130 US.

How does the IC-705’s battery endurance compare with the Elecraft KX2? I’m not sure yet, but I’m guessing the KX2 will have even better longevity as its current drain is less than half that of the IC-705. The KX2 will operate at 10 watts output for about 1 hour 15 minutes with the internal battery pack, before decreasing to 5 watts output. I’ve never tried a battery endurance test with the KX2 at only 5 watts.

Of course, with an external 12 volt battery, the IC-705 will pump out a full 10 watts of power as well.

Five watts and a wire–wow!

The biggest surprise of the day?

I worked stations from Oregon, and Saskatchewan to the Azores…in single sideband!

Here’s a map of my contacts–red signal paths are SSB, CW in green (click to enlarge):

This was one activation where 5 watts SSB actually snagged more DX than CW. Great fun!

While I’d like to think it was a little IC-705 “mojo” on its first field outing, in truth it had everything to do with the EFT-MTR antenna and what must have been a moment of propagation stability.

This was also my maiden voyage with the CW Morse Single Lever paddle. CW Morse sent this paddle, along with their double lever paddle and a selection of straight keys, for me to evaluate. If you’ve been considering an affordable, portable single-lever paddle, this is a brilliant one. I really enjoyed using it and the action is very easy to adjust.

I’m already regretting the decision to send it to my buddy Eric (WD8RIF) for a proper evaluation. (Just kidding, Eric! (Maybe.)) He only uses a single lever paddle for his numerous field radio adventures.

Eric will give this single-lever paddle a proper workout and give us a full report.

I must admit, I had a lot of fun with the IC-705/EFT-MTR antenna combo.

Of course, I’ll be taking the IC-705 to the field a lot in the coming weeks.

IC-705 Questions?

Feel free to comment and ask any questions you may have about the IC-705. I’ll do my best to answer them.

One week and eight parks with the lab599 Discovery TX-500

Over at our other radio blog, the SWLing Post, I’ve been publishing reports and videos of the lab599 Discovery TX-500 general coverage QRP transceiver. If you haven’t been following those posts, you might like to check out the following articles in particular:

Mountain Topper MTR-3B power, speaker, and earphones recommendations–?

I received my Mountain Topper MTR-3B last week, and I’ve already taken it on a POTA activation.

POTA Park Hampton Creek Cove

Last weekend, I decided to break it in on a POTA “two-fer” site: Hampton Creek Cove State Natural Area (K-6246) and The Overmountain Victory Trail (K-4577) in Tennessee. Hampton Creek Cove was actually an ATNO (all time new one) so it was a trial by fire!

POTA Park Overmountain Victory Trail

In short, the MTR-3B was marvelous. I’m so impressed.

As I mentioned in a previous post, I’m building a full SOTA/POTA activation kit for the MTR-3B. I already have a kit built around my KX2 and I don’t want to “borrow” any items from it (so I’m not surprised later in the field when an item is missing).

The TalentCell Rechargeable 12V 3000mAh Lithium Ion Battery Pack is the little black box.

For this activation, I powered the MTR-3B with this inexpensive 12V battery pack a friend recommended on Amazon.com (affiliate link). The battery pack is almost identical in size to the MTR-3B and works perfectly. The battery, charger and cable all set me back a whopping $25.

I also used my Whiterook paddle (which needs new paddle arms at this point) but that will soon be replaced with a set of N0SA portable paddles I recently ordered.

Since the MTR-3B has no volume control, I used a pair of 20 year old Sennheiser earphones I bought when I lived in Munich. These have been in a drawer for ages because I now prefer using in-ear earphones with silicon earpieces for better comfort and sound isolation. But the Sennheisers have one thing none of my other earphones sport: in-line volume control.

While the earphones worked well for this activation, I’d still prefer a set of in-ear earphones with in-line volume control. Any suggestions from MTR-3B owners? Also, I’d like a compact amplified speaker with volume control to carry as an option when needed. If you can recommend one, please comment!

I’m writing an article for The Spectrum Monitor magazine about portable power later this year. I noticed that a number of MTR-3B owners swear by 11V rechargeable cells that are used in the RC and drone markets. Many have a similar compact form-factor as the common 9V battery. I understand, however, some of these cells need special chargers and equipment to balance them.

I would appreciate any and all information about these batteries.

In the meantime, Rich (N8TGQ), recently shared a pic of his Mountain Topper portable pack. Check it out:

MTR Kit

I think it’s brilliant how he’s mounted everything on a compact plastic cutting board inside the case. Rich says that what he loves about this set-up is that everything is there, ready to go–simply plug in the antenna!

I love seeing how others build out their field kits! Please comment or contact me if you’d like to share yours here on QRPer.com!

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

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!

Frank builds the EA3GCY DB4020 Dual-band 40 and 20M QRP SSB Transceiver Kit

The following article first appeared on our sister site, the SWLing Post:

Many thanks to SWLing Post contributor, Frank (ON6UU), who shares the following guest post:


Building EA3GCY’s DB4020 QRP Transceiver kit

by Frank Lagaet (ON6UU)

In May, I discovered via a newsletter that a new kit was available from Javier EA3GCY in Spain.  I was immediately sold as this was a kit from my favourite kit producer and it has 2 bands–it will also be able to do CW and there also will be a CW filter.

After building 2 MFT’s from Javier which work without problems, I needed to have the DB4020.  The MFT’s are for 20 and 40 mtrs and do DSB (double side band).  I did put them in a not-so-graceful box but they do what they are intended for which is QRP phone (SSB).   They came together without problems so I expected the same for the DB4020–I knew for sure when I saw the board:  all through-hole components (except for some capacitors which are factory soldered) and a lot of space on the board.   The board has been silk-screened with clear indications on where all components have to come and the manual has very clear instructions where each component has to be soldered with referral to a quadrant.  The manual provides a 252 quadrant page so it is a piece of cake to find where each piece goes.

What do you get?

Javier provides you with all components which need to be installed on the board and, of course, the kit board.  The components come in small marked plastic bags and all is well-wrapped up in bubble wrap.  The board is wrapped separately and that is put together with the component wrap which is then again wrapped up in bubble plastic.  All goes into an envelope.  Very well packed I must say.

Here’s a picture of the bags with components:

The silk-screened board:

I started with the resistors since that’s the easiest way. After that, I did the capacitors.  I like to solder in all flat components first, so next were the diodes and IC sockets followed by the elco’s.  The transistors were next together with all relays.  As you solder in the transistors one also has to mount the cooling heatsinks,  these cooling sinks are high and are ideal to protect the coils one has to make,  they also protect the polystyrene caps (which I always find vulnerable) when the board is upside down.

Many kit builders are afraid of winding the toroids in kits–don’t be!  It is easy.  Just take your time and follow the instructions given by Javier in the construction manual.  In this kit the builder has to wind 8 toroids:  6 are a single wire which goes through the toroid body,  1 is a toroid with 2 different windings, and 1 has a twisted pair which goes through the final toroid.  Be sure to measure the wire you need per toroid as instructed in the manual.  Javier gives some spare, so you can be sure.  You will also see that on next picture where the legs of the toroids have not been trimmed yet.  Once done I still had some centimetres of wire leftover.

Picture of the toroids ready to be soldered in:

Finally all other parts and pin headers went in,  jumpers were immediately put on where needed.

As I’m using a military-grade plastic box, I have to break-out some components like the display,  tuning encoder,  volume and rx control from the board.  I also have put an on/off switch on the box and already have the CW KEY connector ready installed. I also installed a loudspeaker in the box.  The SI5351 board and the Ardiuno Nano are the final components which go into the board after installing all wires.

Picture of the board:

I intend to attach a CW paddle to the box made out of a relay.  A HWEF tuner (from EA3GCY) which I was planning to incorporate in the box is I think a bit overkill. That HWEF tuner is already in a nice little box and would be a pity to dismantle,  also I’m running out of space in the box…  Maybe I can fit in a 9-1unun which would then give me good results on both bands…?

Maybe I will install a battery pack in the same box.

The box with board installed:

The box completed front side:

Mind you,  it still needs some additional switches for the CW part of the transceiver.

73
Frank (ON6UU)

Video


Brilliant, Frank! I really appreciate the video as well–sounds like the kit produces smooth audio and should serve you well. No doubt, that military box enclosure will survive even the roughest field conditions!

Click here to check out the DB4020 kit at EA3GCY’s store.