QRPGuys LA3ZA Zero Beat Indicator

Image: QRPGuys.com

Some time ago QRPGuys approached me and asked if they could make the low-power zero-beat indicator that I made many years ago available as a kit. I was surprised and very honored by this request. It's been available from them for a while now and here is a description from their page:

The QRPGuys LA3ZA Zero Beat Indicator gives you a visual indication when you are tuned to the callers frequency, based on the tone of the received signal you hear on your transceiver. The theory is simple. The device takes into account the amount of built-in offset your transceiver has, usually around 300-800Hz, and illuminates an led when it detects that specific tone you hear when you are tuned to transmit on the callers specific frequency.

Simple interference fix for the Chinese Pixie

The Chinese Pixie transceiver operating at 7023 kHz has become very popular. It often costs less than 5 USD on Ebay. Like most Pixies it is susceptible to broadcast breakthrough and intermodulation. Much of this is caused by the keying circuit of the audio amplifier, the LM386. The cure is to move the muting diode from the power supply pin (no. 6) to the bypass pin (no. 7). I have described this in another blog post with title: "Using pin 7 of the LM386 to reduce BCI and add side tone to Pixie 2".

Here are two pictures that show how this can be done for the Chinese Pixie. One needs an additional resistor in the range 10 - 51 ohms. If you can fit it, then use the large 51 ohms resistor that come with some of the kits (I think it is meant for a dummy load). I have used 10 ohms in the picture. It replaces the old R3 of 1 k. The diode D3 is not mounted in the holes provided, and instead it is mounted under the PCB with the minus (denoted by the ring) connected to where D3's minus was, and the plus side connected to pin 7 of the LM386.

R3 is indicated by the lower left arrow, and the old
placement of D3 is shown with the upper arrow

I think we have a pile-up ...

TX6G on the Austral Islands of French Polynesia is calling for EU stations on 14026 kHz CW. I hear him well at level S7, but the pile-up stretches up to almost 14033 kHz. 

What can a small gun do to get through? 

Proposal for a fourth ultimatic mode: First paddle priority

The ultimatic mode is an alternative to the iambic mode for sending Morse code from a dual lever paddle. When pressing both paddles the last one to be pressed takes control, rather than the alternating dit-dah or dah-dit of the iambic mode.

In the K1EL Winkeyers there are actually three ultimatic priority modes. This is shown in the table below that comes from page 9 in the specification for the command for setting the PINCFG Register. (K1EL CW Keyer IC for Windows Winkeyer2 v23 10/5/2010). This is a de facto standard for interfacing to and controlling a keyer, as an example it is used in the K3NG Arduino Open Source Morse keyer.

K1EL has defined bits 6 and 7 for setting this up by remote command. I propose that the last possibility, '11', presently undefined and unused, be used for a new mode. This mode is "First paddle priority" meaning that the last paddle which is pressed is ignored. It can also be interpreted as an emulation of a single-lever paddle. I and others have found that helpful in eliminating errors when keying. See for instance "Single Paddle operation with Iambic paddles" by Larry Winslow, W0NFU, in QST, October 2009 and the Iambic to Single Paddle kit from WB9KZY or my earlier blog post "Single-lever and ultimatic adapter".

My proposal is that the bits for the ultimatic mode be used like this:

• 00 - Last paddle priority, i.e normal ultimatic
• 01 - Dah priority
• 10 - Dit priority
• 11 - First paddle priority or Single Paddle Emulation (New)

---

Related posts:

• Single-lever and ultimatic adapter
• Is the ultimatic Morse keyer really that efficient?

Non-English display for the K3NG Arduino Morse keyer

German, Swedish, Danish, Norwegian, Finnish, and some Spanish characters in the display are now supported by the K3NG Arduino Open Source Morse keyer. I have worked with OZ1JHM, Hjalmar and K3NG, Anthony, in order to implement this using the 8 custom-designed characters of the LCD display (based on the Hitachi HD44780). This should satisfy the call I had for such support here on this blog last year: Which non-English Morse characters are the most important ones?

Here are examples using the phonetic alphabets of these languages.

1. For Norwegians and Danes - Æ, Ø, Å:

Norwegian: Ærlig Østen Åse

Danish: Ægir Ødis Åse

Single-lever and ultimatic adapter

Photo @LA3ZA 

Here's an adapter that emulates both a single-lever paddle mode and the ultimatic mode. It is meant to go between a dual-lever paddle and an iambic keyer. The adapter has been implemented in an AVR Butterfly in C and it is compatible with Morse keyers such as the one in the Elecraft K3 and the K1EL WKUSB. The single-lever emulation is probably the most novel part and it is meant to make it easier to practice single-lever keying on a dual-lever paddle.

Studies on Morse code recognition

Nice drawing of Morse key by Dutch
radio amateur Dick Kraayveld, PA3ALM
(http://www.morsecode.nl/pa3alm.html)

In the early 90's there were some interesting studies performed on Morse code recognition and the effects of pitch frequency, signal to noise ratio, and code speed. They were part of the PhD work of Peter Montnémery who is a medical doctor and also radio amateur SM7CMY. I reread these papers now since there was a discussion on the pitch frequency (CW pitch resolution) just recently on the Elecraft mailing list. This discussion comes up from time to time, as it did for instance in 2006 also (Sidetone questions -- copy speed vs sidetone pitch).

The two first papers are probably the most interesting ones for radio amateurs, so therefore I have posted their abstracts and a key figure from each of them also.

Q codes from the streets of Paris

I had the privilege of living in Paris with my wife a few years ago. At that time, 2008/2009, the series for car license plates had just come to Q. That made it easy to find plates with many of the Q codes which are used as abbreviations in radio communications. What follows is the result of walking the streets of Paris, mostly between the 5. and the 13. arrondissement:

Here is a broadcast to all radio amateurs: 

The advantage of the single-lever paddle

My single-lever PCB keyer.

It may seem like a bad idea to downgrade from a dual-lever paddle and iambic keyer to a single-lever paddle. It must be inefficient since each individual dash and dot has to be generated by a right or left movement of the paddle. Despite this, many of the champions in the High Speed Telegraphy competitions use single-lever paddles, often home-made ones. How can that be?

K7QO, Chuck Adams, wrote "Using an Iambic Paddle" and compared the dual-lever paddle with the single-lever with respect to number of movements. If all 26 letters of the English alphabet and the numbers from 0 to 9 are sent, the single-lever paddle requires 73 strokes while a dual-lever and an iambic keyer requires 65. This is 11% less.

But when N1FN, Marshall G. Emm, wrote "Iambic Keying - Debunking the Myth" he analyzed the 7 letters that are faster to send with an iambic keyer - C, F, K, L, Y, Q, and R - and found that only one of them, the L, is among the 12 most frequent ones in English reducing the gain in efficiency to only 5%. He illustrated it this way:

Guess what't wrong with this figure? He didn't see the R and forgot that it is also among the most frequent letters.

Is the ultimatic Morse keyer really that efficient?

Vintage Ten-Tec Ultramatic Keyer KR50. Nice name but the
similarity to ultimatic seems to be coincidental.

Iambic keying with a dual-lever paddle is by far the most popular form for Morse keying. But in recent years an old alternative has reemerged. This is the Ultimatic mode which goes back to W6SRY in the 1950's.

The experience seems to be that it needs less timing precision than the iambic mode for letters like A, N, R, and K (· —, — ·, · — ·, — · —). When both paddles are squeezed, the last one to be pressed takes control. So when right-left is pressed one gets a dah followed by dits, not the dah-di-dah-dit of the iambic keyer.

It is very simple to add code for an ultimatic keyer to an iambic one. In recent years this has led to an ultimatic option in some stand-alone keyers, such as:

Which non-English Morse characters are the most important ones?

The Morse code for the 26 letters of the English language and the digits, you can find everywhere, e.g. here on Wikipedia. All one-, two-, and three-symbol combinations are in use.

In the international alphabet all but four of the four-symbol combinations are used. They are:

Morse	German ++	Norwegian/ Danish	Spanish	Esperanto	Polish 16.3.2014	Greek	Russian	Arabic
·-·-	Ä	Æ	-	-	Ą	-	Я	ع
---·	Ö	Ø	-	-	Ó	-	Ч	ز
··--	Ü	-	-	Ŭ	-	-	Ю	-
----	Ch	-	Ch	Ĥ	-	Χ	Ш	ش

The two or three first German letters are used in many other languages also, e.g. Swedish, Finnish, Turkish, Hungarian etc.

Note that the Ö/Ø Morse code is an O (---) followed by an E (·), usually written as OE. OE also happens to be how the letter is written if the proper symbol isn't available. That also shows the relationship with the French Œ, but that's a digression that has little to do with Morse code. Likewise, the Morse symbols for both the Ä/Æ and the Ü start with the non-accented letter and are AA and UT respectively.

Amazing Reverse Beacon Network

I haven't called CQ for a long time on CW except in contests. Mostly I have just responded to DX calls with a super short "5nn TU" and that's it. But this Saturday I heard a presentation at the Norwegian Ham Meeting by Roland, SM6EAT about a Swedish initiative to increase CW activity. It is called Scandinavian Open CW Activity (SOCWA) and it has at present 452 members from Scandinavia in a wide sense of the word. It really got me interested in improving my CW skills.

So now I have started to call CQ SAX and have had my first long CW QSOs for years with SM and OH.

It is also amazing to look at the reverse beacon network and watch your own CQ being reported almost in real time from various Software Defined Receivers with CW Skimmers. Below is the result of the two CQs I have sent these two last days.

QOD7 - Can you communicate with me in Norwegian?

The Oseberg viking ship, 820 AD

Not so many nationalities are included in the exclusive group of countries with their own Q-code. I mean of course the QOD-code. I have never heard it used by radio amateurs, but it must have played a role some time ago in shipping.

The Q-codes date back to 1912 and were meant to be a short-hand for use in telegraphy. According to the list of Q-codes which Ralf D. Kloth (DL4TA) has on his web page, the meaning of QOD with a number added is: "Can you communicate with me in ... 0 Dutch, 1 English, 2 French, 3 German, 4 Greek, 5 Italian, 6 Japanese, 7 Norwegian, 8 Russian, 9 Spanish?" As a response to the question the meaning was "I can communicate with you in ..."

The reason for a separate code for Norwegian must be the historically large shipping fleet in Norway. This is still the case as graphically depicted in this overview of the Top 20 Ship Owning Countries, where we seem to rank as number seven - so QOD7 is appropriate!

But today all of them will QOD1.

Image from Wikipedia, user Karamell

Nostalgia from LA3ZA in 1949

I wasn't even born when this LA3ZA QSL-card was issued in 1949. This is because I am second generation LA3ZA after my father. When the callsign was reissued to me in 2001 it had been inactive for 40 years or so.

I still have the Hallicrafters S40A receiver which my father used with a 2 W input homemade tube transmitter. The S40A (image below) was what introduced me to shortwave listening during the good conditions of the solar peak in the late sixties, despite its mediocre performance I would say.

Will I ever complete "Worked All States"?

Here's my map of confirmed US states as it has slowly been filling over the last 10 years. 41 states have been confirmed on CW on Logbook of the World, while 9 are still missing.

In recent years progress has been very slow so I don't see my WAS being finished any time soon. Perhaps there is some resource on the web that could assist me with arrangements for the remaining states, or even some readers in these states who would help me?

Reliable auto-detect for keyer for Elecraft K2

The Elecraft K2 has an autodetect feature for the keyer input. When enabled, and when the DASH and the DOT lines are keyed at exactly the same instant in time, the K2 will detect that this is a hand key or an external keyer. I and several other K2 owners have however experienced erratic action of the autodetect with seemingly random keying.

My problem only occurred when keying was done from an external keyer. This could happen when keying from e.g. the WinKeyer.

Simple IKEA transmit indicator

IKEA Oleby automatic wardrobe light with passive
infrared sensor upper right and four LEDs in the center.

Passive Infrared (PIR) detectors have the bad habit of being sensitive to radio frequency (RF) radiation. This can be a nuisance for neighbors of radio amateurs. But we can use this property to our advantage as this makes them suitable for transmit indicators next to a feedline.

The IKEA motion activated LED sensor light, which one can get for a few dollars or euros, turns out to be quite simple to hack for this purpose. You can only buy them in pairs so the other one can be put to use in the darkest wardrobe you have.

All I want for Christmas is a nerdy watch

As a self appointed nerd I have a special fascination for watches with binary displays or with morse code readouts. It seems as if such watches now have become designer objects. One reason may be that since everyone has a mobile phone with a clock these days, design can be promoted at the cost of functionality. Anyway, here are some nice watches to choose from for your wish list!

Personally I find the watches from The One to be among the nicest. Here is the Slim Square. The display is a bit hard to read, binary as it is. The trick is that the left-hand side shows the hours and the right-hand side minutes. Then just add up to get the hours and the minutes.

Three paths from Japan to Norway along the grayline

The Japanese station JA3YBK was received in Oslo (press here for audio), 30. November 2003, 08:20 UTC on 21.004 MHz during the CQ WorldWide contest. The sound is reverberant due to the multiple copies that are received. This can be seen as extra signals, and it is in particularly easy to see after the first short dot (‘e’ in ‘test’).

Propagation via aurora reflection

Northern Lights in Tromsø, Norway 

Here is a recording of the Swedish station SM6CNN in contact with me on 29. October 2003, 22:42 UTC on 28.024 MHz. The direct distance is about 275 km.

Note the noise-like signal which is typical for signals that have been reflected off the aurora on the higher HF and on VHF frequencies. There was a strong geomagnetic disturbance that day with the K-index at Dombås, Norway reaching a value of 9 which explains the occurrence of aurora reflection.