Building a QRPGuys 40/30/20m DSB Digital Transceiver Kit

Though I haven't post something on my blog a couple of months now, that doesn't meant that I was idle.

First on the construction bench sat quoting from their site: 

"...  The QRPGuys DSB Digital Transceiver is a low cost, multiband, DSB transceiver kit, currently with three easy plug-in band modules for 40/30/20m, (additional module pcb’s available). This transceiver is an evolution compiled from various DSB and digital designs on the internet from ZL2BMI, VK3YE, AA7EE, BD6CR, and others. With help from Jim Giammanco, (N5IB) and finally Steve Weber, (KD1JV), we are offering a transceiver with an approximate output of 2.5 watts on 40m, over 1.5 watts on 30m, and over 1 watt on 20m. The receiver sensitivity was measured at .4uV (-115dBm). All the components are included for the main board (3.0″ x 3.12″) and three (40/30/20m) band modules.

The transceiver will run the popular free WSJT-X software (Windows, Linux, or macOS) that requires an accurate time synchronization program, such as Dimension 4, or many of the other free ones available. Users will need two 3.5mm stereo jumpers to your computer or tablet microphone/speaker jacks on the sound card.

The transceiver’s internal VOX circuit will switch to transmit automatically when it senses an audio output signal from the software on the pc or tablet speaker jack. The connections to the transceiver are BNC for the antenna, 3.5mm stereo jumpers to the computer audio jacks, and 12-14 VDC for the pcb mounted 2.1mm pin coaxial power jack. Approximate power consumption is about RX-15mA/TX-350mA. The total weight w/band three modules is 3oz. (85gm). The normal tools required are a soldering iron with a small tip, rosin core solder, and small side cutters. The transceiver can be built in an evening. On a difficulty scale of 1 to 5, 5 being the most difficult, this is rated at 3 depending on your experience. Note also below, plans for building a 3.5″ sq. x 1.0″ high compact chassis from PCB material. ..."

This certain kit is retired now replaced by the Digital Transceiver II kit which has an optional Digital VFO board so the user can choose the Tx frequency and Tx Mode to bands from 160m – 17m.

It can easily constructed in one evening and in my Scale of Difficulty is a fair 2! As long as you are familiar with PCB soldering and toroid cores winding, is a piece of cake!

You can find the old version here but the newer and better is the one I strongly suggest to construct! 

The kit I've constructed gave me 4W on 7.074MHz, 2W on 10.136MHz and 1W on 14.074MHz. Definitely not enough power to set alight the Ionosphere but more than enough to have a constant flow of qso's!

Enjoy your time and @staysafe 

73 de sv3auw/m0lpt

The Cricket

The Cricket: The Four State QRP Group’s latest transceiver kit

 Here's a hot tip for those of you who enjoy building transceiver kits:

The Four State QRP group has just released The Cricket: a simple 80 CW transceiver kit. The Cricket was designed by David Cripe (NM0S) who is behind a number of successful kits (including the Ozark Patrol and the Bayou Jumper).

The amazing part about this kit is that it's super simple, has no toroids to wind and doesn't even need to be aligned. It even includes a Morse key.

All this shipped for $32.68 in the US, $39.50 in Canada and $43.50 for international orders. A serious bargain, in my book.

Typically, Dave's kits sell out the same day they are posted for sale. If you're interested in The Cricket, don't hesitate to order! (I just bought three, for example.)

Click here to order The Cricket.

 Here's The Cricket kit description via the Four State QRP Group website:

Kitted and Offered For Sale By The Four State QRP Group

The Cricket is a low cost entry level minimalist CW transceiver for the 80 meter band. Chosen as the build session kit for OzarkCon 2017, it bears a family resemblance to the well known but much lower performing Pixie. However it is very different and vastly improved over the Pixie. This is NOT a Pixie, it is far superior! It features low parts count, better components including MOSFETs for better sensitivity and switching, and a modern NJM2113D audio amp.

A TX/RX offset is also incuded so that you can work other stations that have zero beat you, or are using a crystal on the same frequncy. Full QSK and a sidetone complete the essential operating features. Dave's famous etched spiral coils are included on the pc board, so there are NO TOROIDS to wind. Additionally a straight key is included on the pc board, just snap it off, mount it on the board, and the whole rig is then self contained. Also included is an electronic keyer adapter - you can use your favorite keyer with the Cricket! These are many features for such a low parts count and inexpensive transceiver.

ALL THROUGH HOLE parts make this kit very easy to assemble. It will make a fine, fully functional, and educational first rig for a new builder, the new ham, or seasoned veterans wishing to just have fun with a new rig at minimal expense and effort. Note that Novices and Technicians have 80M CW privileges from 3.525 to 3.600, same as everyone else - so they also can build and use the Cricket.

This simple rig is fun and functional, and made many contacts at OzarkCon after the build session. A proven design and a great choice for your next rig, it is perfect for a group build with nets and contacts after the build. This is an excellent club project.

QRP Q&A

What is, QRP?
QRP is a term adopted from the international RQS signals meaning to reduce
power. Hams have taken this term and its meaning to be low power.
Generally, ORP is 5 watts or less from the transmitter, regardless of the input
power to the transmitter. If you hear someone on 40 meters calling CQ QRP,
he (or she) is calling for a low power station. More than likely, they will be using low power, too.

What is, QRPp?
QRPp is the older term for RF power of 1 watt or less. That extra small "p'
meant really low, low power, generally under 1 watt. That term has been replaced by the term "miIliwatting." While it may be hard to believe, you really can work around the world with an output power of 50 milliwatts! There have been many hams working DXCC with only 100 milliwatts to the antenna. It is hard to do, but not impossible.

What are the most popular QRP bands?
There really is no one band more popular than the others. You'll find QRP
operation everywhere from DC to Light. But, some consider the 40 meter
band around 7.040 MHz to be QRP Central. You can also find some action
on 7.035 MHz and 7.060 MHz. In the winter time, when summer QRN is
down, 80 meters is very popular during long cold nights. There is QRP activity
on 160 meters, too.
The 30 meter band is a QRPer's delight! Try 10.106 and up for low power
signals. Then, let's not forget about the 20 meter band either. This is by far
the most popular ham band when it comes to working DX. Low power operation used to be located around 14.060 MHz, but alas, other forms of digital signals have been moving down, overtaking the QRP-calling frequency.
Check the entire band for QRP operators-they're everywhere on 20. You
can find QRP signals on 17, 15, and 10 meters, too.

I'm not into cw, Can I still operate QRP?
CW is by far the most popular mode of QRP operation. It's partly because
CW transmitters are easier to build than SSB rigs. With CW, you get more
bang for the watt, too. But QRP is not only CW, it's any rnode you want to use, including FM or SSTV. QRP means low power-not CW only. 

Do I need to change rigs or equipment to operate QRP?
Of course not! Most of today's rigs can be easily turned down from a front panel control. You'll end up with low transmitter efficiency, but you won't have
to spend a penny.

How about antennas? All I have is a simple dipole.
No matter what power level you use in amateur radio, the better the antenna.
the better your signal will be. Use a good grade of feed-line and get the
antenna as high as possible.

I enjoy a good contest now and then. How can I compete with other stations if I run only 2 watts?
Most of the major contests, such as the CQ World Wide DX contest,
Sweepstakes, and even Field Day, have special low power sections. You only
compete against others within the same power class. You don't have to worry
about the guy running a kW because you are not in the same class!

I know many QRPers like to build their own gear. I'm not much of
builder. Can I purchase a commercial QRP transceiver?
It's too bad you don't like to build your own gear. You're missing out on a
lot of fun. But yes, you can purchase a commercial QRP transceiver.
There are many other mono-band rigs, such as the MFJ, Youkits, Hendricks, etc available. 

 Almost all of the circuits I've seen in the last decades have been 
solid-state transmitters. How about us guys with boxes full of tubes?
It is the 21 Century and today's technology is solid-state and microprocessors.
But, if you want. you can still use a vacuum tube in a QRP transmitter. The
best place to look for a circuit is in an old copy of the ARRL Handbook. Begin
looking with the early '70s and work your way back to the '50s. Parts for
those circuits may be next to impossible to locate, unless you have a really
big junk box!!!
Can I operate PSK31 or JT65?
Yup! Sure can. Again, QRP simply means low power. Any mode of communications is suitable for QRP, with the exception of moon-bounce! I've had some great QSO's using PSK31 with less than 4 watts PEP.

Are there any QRP clubs to join?
Yes! As a matter of fact I'm member of the British G-QRP which is based in United Kingdom and publish SPRAT which is full of construction projects. Almost every Radio-Society run and support a QRP department. There is also the SV-QRP group and their bimonthly e-magazine sv-qrp!
I like to collect awards. Can I still do so with QRP?

Yes! There are many, many awards issued just for QRP operation. These
range from a DX contest with QRP endorsement to the Miles Per Watt Award .
Many other contests also provide a special QRP award such as the ARRL's
Sweepstakes or the CQ World Wide DX contest.
What are some of the limits of QRP?
QRP is not push-button communications! There will be times when your 2
watts just won't cut it. Band conditions, QRM, sunspots. and QRN all take
their toll on a 2 watt signal. There will be times when your 2 watts of RF won't
be enough to make a contact. Some modes don't seem to work as well as others. SSB, for example, is much harder to do with QRP power levels because everyone likes that arm-chair copy. You won't be armchair copy most of the lime on SSB. AM phone is really tough on QRP! It's possible to work All EU with AM phone on the 10 meter band using QRP, but on 75 meters and 40 meters  its not going to fly!

I'm on a limited budget. Would QRP be the best way to go to enter ham
radio?
QRP means low power, not inferior equipment! Don'1 get the two mixed together. 
You could pick up a simple Kit at a hamfest or E-bay for under 50Euro and have a ball, or your could drop five thousand for an YAESU FT-5000, turn the drive down. and run QRP too. While it is true you can pick up a brand-new rig such as the K-1 QRP mono-band rig for about 200Euro, compared to about 1.000E for an entry-level 100 watt rig, going QRP would save you money, but at a cost of only one band and being stuck with CW only.

If I start to operate QRP, what's in it for me?
No matter what you do in life, you get out what you put in. QRP really boosts your ego. Breaking a DX pile-up with 2 watts will keep a smile on your face for weeks. Working the east Coast with 1 watt from a transmitter you
put together with your own hands is one of the best ways to generate those
warm fuzzy feelings. If you're tired of the quick, "Hi. Rig here is .... Weather here is ... Five-Nine..." type of QSO, give QRP operation a try. And if it's nothing else -it's FUN!

RS-HFIQ 5W Software Defined Radio (SDR) Tranceiver

While there are a fair amount of SDRs in the $200-300 price range, there are few that are actually transceivers.  I'm also impressed with the level of filtering on both the RX and TX stages and the fact that the baseband and digital section have separate and isolated grounds. The RS-HFIQ could potentially have a low noise floor and a decent front end.
The SWLing Post.

Product Summary

Not just another SDR - The RS-HFIQ offers real RF performance for serious communications. Covering the 80-10M Amatuer Radio bands with excellent RX performance and 5 watts of TX power, using open-source SDR software for CW, SSB, AM, FM and digital modes, the RS-HFIQ sets a new standard for shortwave SDR communications.
RS-HFIQ 5W

Με κόστος λίγο πιό πάνω από έναν SDR Δέκτη, μιά νέ εταιρία κυκλοφορεί αυτόν τον ΠόμποΔέκτη! Με την αξιοπρεπή ισχύ των 5W στην έξοδο και με τα χαρακτηριστικά του, τουλάχιστον στο χαρτί, να είναι πάρα πολύ καλά, είναι μία συμφαίρουσα αγορά. Καλύπτει όλα τα Modes και φυσικά είναι p'n'p στα Ψηφιακά! Τι SDR θα ήταν άλωστε αν δεν τα υποστήριζε;!
Κάνετε υπομονή κι όλο και κάποιος θα τα αγοράσει. Τότε θα μάθουμε κι εμείς πόσο καλό είναι στον "αέρα".

KR80 QRP Tx finished (almost!)

I was waiting for a 14Megs Xtal to finish the project or at least to make it start working and then make the necessary improvements.

First thing first, it needs more capacitance at the outpout/ATU circuit. The excellent variable capacitor I am using has a top capacitance of 95pF. I have to solder another one in parallel and take it from there! I'll keep you posted!

Καθυστέρησα λίγο γιατί περίμενα να μου στείλουν μερικά κρύσταλλα από την Αγγλία. Θα μου πείτε γιατί δεν τα αγόραζες από εδώ? Να σας απαντήσω ότι αυτοί που πουλάνε συρματόσκοινο για αγωγό RF, ήθελαν να βγάλουν κέρδος κι από την κούριερ. Έτσι για να ξέρουμε τι λέμε επί της αρχής.

Από εκεί στα δικά μας τα κατασκευαστικά, ταλαντώνει, κατεβαίνει μέχρι το 14.001MHz αλλά, μου λείπει χωρητικότητα από το ATU. Ο ωραίος μεταβλητός τον οποίο βλέπετε στην φωτό, έχει φύλο PTFE μεταξύ των βανών και αντέχει πολλή παραπάνω ισχύ από αυτή που μπορεί να δώσει ακόμα κι ένα υπεροδηγούμενο BD139 Ατυχώς είναι μόνο 95pF κι έτσι θα πρέπει να παραλληλίσω ακόμα έναν κι ίσως κι έναν τρίτο. Ασύμφορο κι αντισυμβατικά αλλά πολύ κομψό!

Θα έχουμε και συνέχεια με δοκιμές!

 

KR80 QRP Tx

That is a QRP transmitter having an interesting and uncommon output circuit. I will built it using a different approach on construction than the usual ugly or Manhattan. It is designed by Keith Ranger G0KJK and published in SPRAT Autumn 2015. More photos to come.

All I had to do was to design the transmitter on a piece of graph paper taking in consideration the dimension of the discrete components. After I mark the holes with a scriber, I drill them using a 0.8mm drill bit somewhere near! hi! hi!

This method of homebrewing calls the use of solder-able magnet wire to make the interconnections. I use the components leads instead!

During the build I found out that I don't have any 14.060MHz xtals left in my drawers so the 2N3953 transistor. It is easy to order an xtal, or many, from the club sales which I did promptly but the transistor seems to rare as hens teeth! As I comment to a Greek colleague I will use what I have in my stock and that is a PT4579.

Hard boiled and annealed inductors!

RCA 813 QRP transmitter!

The well-known radioamateur motto dictates to Listen, Listen and Listen again.
Since the presentation of the GU-81 regeneration receiver you had your chances to listen enough.

Now its time for you to transmit!
I'll give you the initial kick along with photos and the schematic for a QRP Tx based on the 813 tetrode tube!
Gentlemen, (and Ladies of course), warm your irons!

Μετά τον δέκτη ανάδρασης με την GU-81, τώρα κι ο ανάλογος πομπός.
Αυτοταλάντωτη 813 με κρύσταλο και QRP ισχύ εξόδου! (λέμε τώρα!)

Home-brewing Mixer IC's. CA3028A

In the quest of the ultimate home-brew project I follow the idea and the schematic of fellow K.P.S. Kang to made myself an equivalent of a factory made Mixer IC!
I should have used 1/8W resistors other than the 1/4W I used in an effort to keep the foot print to a minimum. Never the less, there are no short circuits and the proof of working is to build a radio around it!
Thank you very much OM for the excellent idea!

Δεν υπάρχει έλλειψη σε Ολοκληρωμένα, ακόμα, αλλά καλό είναι, των φρονίμων τα παιδιά να είναι προετοιμασμένα! Βασισμένος στην ιδέα και το σχέδιο του K.P.S. Kang έφτιαξα την αντιστοιχία του CA3028A με διακριτά εξαρτήματα.
Το πόσο καλά δουλεύει θα το ανακαλύψω σύντομα όταν θα το εντάξω στον υπό κατασκευή QRP π/δ!

SV, Spring gathering on 40m band.

After I check both of the given frequencies, I start calling at 7.135MHz at 10:05 Local time (07:05 UTC). The, by gentlemen international agreement, QRP calling frequency was occupied by a non gentleman calling "chi ckou quaranta - chi ckou quaranta metros". The alternative frequency of 7.135Mhz was free(!) so after the typical " is the freq. in use, is the freq. occupied" I place a call and in a few minutes the first taker was SV8QG. Most of the Q=code was around today with fine examples like QSB-QRM-QRK and so on! For the easiness of typing I will use 5-9 for all reports although the recipients have a fully detailed report of our QSO.
so first was SV8QG 5-9 Loc KM39GC
then was SV1EPN 5-9 Loc KM17VT
then was SV1OMW 5-9 Loc KM27AV
then was SV1IVK 5-9 Loc KM27AV (operating from SV1ONW shack)
then was SV8CYV 5-9 Loc KM37MQ
then was SV1GRN 5-9 Loc "no copy" (so much for 5-9! but Panos was eager to leave)
and finally was LZ5IL 5-9 Loc KN21IN
I had a full 2 hours of contacting and I do enjoy it very much!
Thank you very much guys and I hope to see you all and many more, next time!
73
Takis
sv3auw

My working conditions was an IC-720A down at 10 Watts SSB power, an EFHW antenna and my trusty Create 730V1 Dipole. Most of the time I was using my EFHW as a better NVIS antenna.


Εαρινή σύναξη των ραδιοερασιτεχνών σήμερα και τα call-sign τα οποία διαβάζετε από πάνω συνομίλησαν μαζί μου. Όλα τα κακά ήταν μαζεμένα παρέα με ένα κόντεστ, την Ι ταλική γαϊδουριά και την απαίσια διάδοση. Ήταν στιγμές όπου κατόπιν συμφωνίας με του συνομιλητές μου ζέσταινα την φου-φου για να χαλιναγωγήσω τα γαϊδούρια! Ήταν δύο ώρες γεμάτες αγνό ραδιοερασιτεχνισμό χαμηλής ισχύος και τις χάρηκα πάρα πολύ! Μέχρι την επόμενη φορά λοιπόν... 73!
Τάκης
sv3auw

More QRP radios!

More QRP radios from the other side of the Pond!
The LD-11 of the LNR Precision and the 

MTR5B 5-Band Mountain Topper designed by Steve "wonder" Weber KD1JV.
The swling post is a real treasure!

Εξωφρενικό κόστος.

Παρήγγειλα από την kANGA UK το Arduino Si5351A shield kit.
Το κόστος του κιτ όπως μπορείτε να δείτε στην φωτογραφεία είναι 29.95 GBP ενώ το κόστος αποστολής είναι 8.50 GBP ήτοι 11.54 Euro με την σημερινή ισοτιμία.

Στην ερώτησή μου στην υπάλληλο της μεταφορικής εταιρίας, για το πόσο θα κόστιζε να έστελνα τον ίδιο φάκελο από την Καλαμάτα στην Αγγλία, η απάντηση που έλαβα ήταν, "περίπου 50 Ευρώ".

Διέσχισε την Ευρώπη κατά μία διεύθυνση, με ενδιάμεση στάση στην Γερμανία και με 11.54Ε ενώ θέλουν 50Ε για την αντίθετη?!
Δεν φταίνε μόνο τα "Μνημόνια" για τα χάλια μας και για την φυγή των "μυαλών" στο εξωτερικό. Φταίει ΚΑΙ η κακώς εννοούμενη "ιδιωτική πρωτοβουλία".
Φανταστείτε το ίδιο κιτ ή κάτι παρόμοιο, να το έφτιαχνε ένας Έλληνας και να ήθελε να το στείλει, αξιοπρεπώς, στην άλλη άκρη του κόσμου. Τσάμπα να το έδινε, ποιός θα πλήρωνε αυτό το εξωφρενικό μεταφορικό κόστος?!

Rock-mite 40 QRP kit. Good 'n' ready!

Another one QRP kit found it's way to the rack!

I finished the construction of it yesterday by winding T1 and T2 toroid transformers.

Pout is approximate 2W. Me thinks that more power than that it is rather unobtainable judging from the characteristics of the output transistor the size of the heat-sink and the turns ratio of the transformers.

My personal advice to any one of you thinking to buy it, is to do it! It will give you a pleasant frustration decoding the Chinglish during construction and then you will award yourself with a small but remarkable rig!

Cheers!

The saga continues!

Rock-Mite 40. The saga* continues!

0(zero) Ohms resistor? Well, it's look like the prefect conductor to me!

More components populated the rock-mite board up to the last two T1 and T2 toroid transformers.

*saga. any piece of writing that tells of heroic events or deeds

Rock Mite-40 QRP kit

Spring is coming so I decided to rejuvenate my mood after a long idle winter, by building a rock-mite 40.
The kit bought from China (where else!) and it came the typical Chinese way. An envelope containing a plastic bag full of components. No manual, no instructions other than "you friend go my site. you read manual weld kit enjoy afterward"!

I promptly done that and "reading manual", I found a lot of mismatches between the schematic diagram and the components values in the component inventory.
For example R3 on the schematic has a value of 0(zero?!) Ohms whereas in the instruction leaflet has a value of 220Ohm.

Nevertheless I bite the bullet and I started the construction.

As usual I started with the smallest components ie the capacitors and I continued with the resistors, mounting almost all of them on vertical position.
I'll let you know the progress.

Restoring and Modifying the HW8

  Restoring and Modifying the HW8 by Takis Perreas

Fault finding, restoring and modifying the Heathkit TxRx HW8 by G0FSP

160m AM TX QRP

Πομπός ΑΜ για την μπάντα των 160μέτρων! (όχι των 180, δυστυχώς.)

The Tripus!

What is a Tripus?

Well, some might know and some might have guessed that it is an invention of Reverence George Dobbs G3RJV. George found that he was constantly going to rallies and seeing meters that he could not check or determine their sensitivity. So he designed the Tripus which have taken on stage further by adding another cell, thus enabling it to check LEDs and seven segment displays.

This simple unit consisting of two cells, four resistors and three crocodile clip on leads which are all held together with tape.

The circuit diagram shows the unit works. When the Black and the Red leads are shorted together, 10miliamps flows across the circuit and when the Black and Yellow leads shorted together,100 microamps will flow.

When testing meters, start with the Black and Yellow leads and if the meters reads half scale the movement sensitivity is 200μA FSD(Full Scale Deflection). If the meter flies over to FSD it is more sensitive than 100microamps, but as the most sensitive meter that you are likely to find will be 50microamps, the meter should not be damaged.

If the meter hardly deflects at all, then its sensitivity is obviously low, and this is where to 10miliamp Red lead can be used! The result obtained enables the sensitivity to be estimated in the same way as with the Yellow lead.

For testing LEDs we use the 10mA lead and this could be enough to illuminate all colours if the battery is fully charged. We can also tell if seven segments displays are common anode or common cathode, as we know the polarity of the battery within the Tripus.

For charging my Tripus, I clip the Black and the Yellow leads onto my nicad charger and charge in the normal way for the cell size used.

And why is it called the Tripus?

Well, it only has three legs!

Ian Keyser G3ROO/Radcom 9402/sv3auw

Μια μικρή και εύκολη κατασκευή για τον έλεγχο των οργάνων και LEDs τα οποία εμφανίζονται στα ham-οπάζαρα.

Ζωντανά ή πεθαμένα! 

20W AMPLIFIER

Ενώ τελείωσε ο χειμώνας κι εγώ, ενώ δεν ασχολήθηκα στα σοβαρά με το winter project, αγόρασα την πλακέτα ενός qrp ενισχυτή από τον Άγγλο συνάδελφο M0RZF, μέσω e-bay. Αυτό θα είναι το... summer project!
(eBay item number:251483994179)