CQ WW DX CW 2024

 

At first I wondered, wheter I would join the CQ WW DX CW contest. Late in the afternoon I turned on the RIG and I listened for a minute.
When I heard the strong signals, I was immediately excited.

Very low power QSO's 
The first 5 QSO's were made in just 20 minutes with a power of 36 mW (1), 80 mW (3) and 3.6 mW (1), on Saterday afternoon.

Two digit milliwatting
On Sunday afternoon I used 80 mW to make an other 6 QSO's with S&P.

QSB

Then the QSB kicked in. So I had to use 360 milliwatt. And on occasion I made one QSO with 80 mW and one with 36 mW. 

Activity in the contest
A major contest offers a great opportunity to make QSO's with low power.
I had great fun with QRPp with 3.6 mW to 800 mW. All with S&P.
I also made 2 more QSOs with 2.7 W on 40 m, but the emphasis was on working with low power.

Confirmed DXCC countries with QRP

This table shows all the confirmed CW QSO's from September 2003 - August 2014, that I made under the call PA1B.

As a milliwatt enthusiast, I lower my power when the S-meter goes up. I often use the lowest possible power in each QSO. I use QRPp, when ever I can, but also use QRP when it is necessary to make the QSO. In most QSO's, I use S&P. This is search and pounce. I search on the band and answer a CQ of a loud station. I start with a low power and only increase my power when I am sure that my signal is not heard. I use attenuators to lower the power for QRPpp and QRPp. In every QSO that I make, I note my power in my log.

The table shows 12 power categories from 1 mW up to 5 Watts. But please notice that a QSO in the power category of 50 mW, can be made with a lower power than 50 mW. A power of 30 mW, 36 mW, 41 mW, 45 mW and 50 mW, are all  displayed in the power category of 50 mW.

Conformed DXCC-countries with QRP  -  PA1B

The total number 8 x 10 + 7 = 87 DXCC's.
I have made this table with great care. Please let my know, if something is not, what it should be.

SWL R4A-1227 confirms 36 mW QSO

It's great to receive a QSL of a SWL station. In the last batch of eQSL's I found a eQSL from Valentin R4A-1227 that really knocks my socks off. This eQSL is very special, because of the very low power, that I used. I made a QSO with MU0RGU. The signal was very strong, so I decided to answer with 36 mW. The QSO was heard by Valentin R4A-1227.

36 milliwatt

R4A-1227  -  36 mW  -  1734 Miles  -  48,180 Miles per Watt

Miles per Watt
This SWL report and the QSO with M0RGU are both good for more than 1000 Miles per Watt.
PA1B to  R4A-1227  over 1734 miles to LN28gm with 36 mW gives 48180 Miles per Watt.
PA1B to  MU0RGU: over  378 miles with 36 mW gives 10496 Miles per Watt.

Thank you Valentin for the very special eQSL. FB.

10 dB attenuators of Stefano IZ1OQU

On my Blog and website I show information, on how I work with QRP and QRPp and the use of attenuators for more than 1000 Miles per Watt QSO's.

Stefano IZ1OQU built a 10 dB attenuator, that I described in an earlier post. (Click to read) With this attenuator Stefano made QSO's with 50 milliwatt in SSB from his home over more than 2000 kilometers, using vertical antenna's.

With a difference of 13 dB between SSB and CW, the 50 mW in SSB can be compared with 2.5 mW in CW.
Congrats to Stefano, for this great achievement.

Stefano has recenly built a light weight attenuator with two sections of 10 dB. He wants to use the attenuator in SOTA and portable operation.
Here is the interesting e-mail from Stefano with photo's of the light weight attenuator.


Dear Bert,
I'm IZ1OQU Stefano. I wrote to you some months ago for the attenuators on your website.
With the 50 mW of the first attenuator that I built, I had my best Miles per Watt SSB QSO's with Finland, Russia and Georgia, over 2200 kms with the top-score of 2700 kms with Georgia: 
54.000 kilometers per watt.

I'm writing again to show to you the new step attenuator that I've made: with switches and 2x 10 dB steps to reach the 5 mW output with my FT-817.
I attached some images of the new toy, made with pcb enclosure. I left one removable side just to shot some photos. You'll see, It's tiny (about 6x3x3 cms size) and low-weight. With that small space it was hard to solder everything but I did it!

I'll look forward to find ways to reduce again the size wile adding more steps but not before some testing: you know, SSB is not the best way to play MxW with such little power but I am still newbie with CW.

I keep following your blog, I shared it to some friends because they also like MxW, QRP and homebrewing things. The MxW comunity in Italy is slowly growing thanks to the WxM (watt per mile, or mile per watt... anyway we call it, it's the same thing) contest.
Go on with your good job

73 from Italy
Stefano IZ1OQU 

Light weight 2 x 10 dB attenuator IZ1OQU 

Stefano will use the attenuator on SOTA and portable operation. FB.
To read more, visit Stefano's interesting QRZ page by clicking on the link.

Lowest possible power

In WSPR analyses I use the lowest possible power to compare the signal strength of WSPR spots.
The lowest possible power is calculated from the transmitted power and the SNR of the receiving station. The lowest possible power is an excellent propagation indicator.

Click on the Tab: WSPR propagation analysis at the top of the Blog for a new explanation on the lowest possible power and a easy to use beatiful table.

Lowest possible power  -  Click to enlarge PA1B

I am proud at the beautiful table. hi.

What is QRPpp

QRPpp is the (not official) term that I use for a power of less than 100 milliwatt.
Here is a nice diagram on QRPpp, QRPp and QRP.

How is it possible to use QRPpp?
Read the post QRPp How is it possible

QRPpp eQSLs

Here are some eQSLs' from the last batch.

The QSO's are all made with QRPpp and while using the Lowest Possible Power.

QRPpp is the (not official) term, that I use for a power of less than 100 milliwatts.
Also known as two digit milliwatting.

Making QSO's with very  low power is not that difficult.
It´s all a matter of propagation.

The changes in propagation can be hugh.

So when the S-meter goes 20 dB up, the power can be reduced by 20 dB.

Look for a station that is calling CQ,with an earsplitting S⁺⁺ signal.
Answer with low power, with the excellent timing, that you always use.
Don´t suspect anything, but be prepared, after you give your call.
Most of the time, other stations are answered.
But than suddenly, when the frequency is clear, then you will be heard.
It´s possible that you are surprised, that you hear your call, being send immediately correct.
And before you know it, you also get an exchange. What was that? What number did he gave? hi.

9H1XT    1205 Miles   3.6 mW   334841 Miles per Watt

IV3ZXQ   550 Miles   22 mW   25002 MPW

SM5QU   740 Miles   36 mW   20549 Miles per Watt

SV1ENG   1318 Miles   98 mW   13453 Miles per Watt

S56M   588 Miles   80 mW   7349 Miles per Watt

OE2008S   445 Miles   98 mW   4698 Miles per Watt

See me smile, from ear to ear, after such a QSO.  

CQ WW WPX CW 2013

In every contest it is possible to make QSO's with very low power.
The stronger the signal, the less power is needed, to answer a CQ.
I had very much fun with low power.
Many of the QSO's are good for more than 1000 Miles per Watt.

REF CW contest 2013

This year I only participated for a total of 45 minutes on Sunday.

In a relaxed way, I used search and pounce with the use of the lowest possible power in each QSO.

The conditions were good for the use of low power on 14 MHz.
On 14 MHz all QSO are good for 1000 Miles per Watt.

Despite the short distance to France, 5 out of 6 QSO's are made with QRPpp*.

On 7 MHz I had to use the maximum power of 2.7 watts in most QSO's.

The changes in propagation can be very large.

In the afternoon, I met a station from Corsica, that I had worked earlier with 360 mW.

I tried to make an second QSO with 36 mW. His signal was S9 + 10 dB. He recognized my call and gave QSO B4. I gave a new report. But then we ended up, transmitting at the same time. So.....this QSO will probably not make it into the log. hi

I enjoyed the opportunity to work with very low power in the REF CW contest.

QRPpp* is the (not official) term that I use for a power of less than 100 mW. Bert PA1B QRPpp

HA-DX contest 2013

I enjoyed working with my new Inverted Vee in the HA-DX contest. At the end of 2012 Walle PE2WJW repaired my antenna which was damaged in a storm late November. The HA-DX contest was the first DX contest,  in which I could test the new antenna.
The new antenna works well.

When I started on Saturday afternoon on 20 m, I heard HA8MD with S8 +20 dB, so I immediately made a QSO with just 8 mW. This first QSO was also the QSO with the lowest power in this contest.
After that I made 4 more QSO's with very low and very low power: HA8IB - 36 mW, RA3RFA - 800 mW, UA2FL - 36 mW and HA1ZH - 360 mW.
A very good start. After that I got on the bike, because it was sunny whether.

On Sunday mornong I made QSO's on 40 m, 20 m and 15 m.
After the contest I went for a walk in the park. Not because it was sunny. It was snowing and there was wind. The very small snow flakes were moving almost vertically, so I could'nt resist. hi

In all QSO's I used the Lowest Possible Power with search and pounce in CW. So the used power in each QSO, is a very good indication of the propagation at that moment.
When I use the lowest possible power, it not always easy. Sometimes I have to give my call many times before my weak signal is heard. The frequency must be absolutely clear.

26 Out of 34 QSO's are made with more than 1000 Miles per Watt, considering the distance to the worked stations.  hi

LZ2HR

Click to enlarge   

I received an other beautiful QSL card from Hristo LZ2HR via the mail. This time the card had 3 QSO's on it. The QSO with the lowest power was made in the UBA contest 2010 in CW on 14 MHz. I used a power of 98 mW and a Inverted Vee, over a distance of 1180 miles resulting in 12041 Miles/Watt. Thanks, Hristo for the beautiful card.

Attenuators and tuning

50 Ohm attenuators
The attenuators shown on the PA1B Attenuator page are all very accurate 50 ohm attenuators. The accuracy is obtained by placing two, or more,  resistors in parallel, to form the required ohmic values very accurately, with resistors from the E12-series.
But the accuracy of the attenuators is also dependent on the termination of the attenuators. 
When the attenuator is terminated with 50 ohms, the attenuator will show also an input impedance of 50 ohms and most important, will give the right attenuation.

Setup

The attenuator will be placed behind the set. The SWR-meter is not shown in the drawing, but is placed between the attenuator and the tuner (transmatch). I work with this setup, as long as I work with the attenuators and by doing so, I made many fine QRPpp QSO's, using an inverted Vee as antenna.

The right setup.        Tune, as accurate as possible, for a SWR of 1:1,

Tuning

Tuning is done with the attenuator on bypass (0 dB). Tune carefully to get a SWR of exactly 1 : 1. When the SWR is 1:1, the input of the tuner will show an impedance of 50 ohms, so later with the attenuator switched on, the attenuator is terminated with 50 ohms and the attenuator will give the right attenuation. It's very important to tune for 1:1 as accurate as you can, to get a termination with 50 ohms for the attenuator.

SWR

I got an e-mail from a follow Blogger, Mike VE3WDM. He was using the autotuner of the Elecraft K3. The K3 is connected to  the SWR-meter, which is connected to the attenuator, which is connected to coax to the antenna. Mike wrote that he had a SWR of 1.6 : 1, with the attenuator on by-pass. Since the autotuner is in the set and the SWR-meter is behind the set, this means that the coax to Mike's attic antenna shows an impedance of 31.25 ohms or 80 ohms. (50/1.6 or 50x1.6)

The e-mail of Mike made me realize, it is not possible to use the autotuner in the set, together with the attenuators. The tuner has to be behind the attenuator. However, it is always possible to use another (homebrew) tuner behind the attenuators. Mike later said that he will place a tuner behind the attenuators and will turn off the tuner in the set . 

So place the tuner behind the attenuator and tune as accurate as you can to get a SWR of 1 : 1, to get the right attenuation. 

K3WW with 100000 Miles per Watt

When I went into the ARRL international DX contest, the first station that I heard was K3WW. K3WW is a station with Excellent Ears.
The signal of Charles was stronger than the usual S8.
The signal was over S9, so I decided to try a lower power than the usual 360 mW and I switched to 36 mW, using a 10 dB attenuator. I expected that I had to use more power, but to my surprise we made the QSO with just 36 mW in CW, using an Inverted Vee.
My FT-817 only gives 360 mW instead of 500 mW after a serious mismatch, but I still have great fun with low power and 1000 MPW.

The distance between my QTH JO22na and K3WW in FN20ii is 3725 miles.
With 36 milliwatts this gives 103000 Miles per Watt.
Thank you Charles for the fine QSO. Hpe cuagn in the next contest.

CQMM DX 2012

I just sent in my Cabrillo file for the CQMM DX contest. I had some trouble to make the entry. I logged on paper and made a Cabrillo file in Excel. But the robot refused my entry based on version 2. So I used an online webform to make the Cabrillo file in version 3.

We were invited out for a birthday, so I only had time on Saturday and only made one QSO before we left on Sunday. I used the Lowest Possible Power in each QSO.
I started, late around 19:45 local time, so the propagation to Europe was good. At first I made some more than 1000 Miles per Watt QSO's in Europe. About one hour later the signals from North and South America came through.
The signal of N2MM was stronger than S9. Carol was S8 through the 10 dB attenuator, so the QSO could be made with 80 mW. The exchange was 599 NAY . The Y means YL.  Later AA3B was also worked with 80 mW.
It is years ago that I met AA3B with just less than 100 mW, so you don't hear me complaining about the propagation. hi.

This CQMM DX contest brought 3 new DXCC's: FM, OX and CE.  
Martinique with 360 mW, gives a very nice QRPp more than 1000 Miles per Watt QSO.

This survey, showing the bands is also interesting. To North America was slightly less power needed at 15 m than on 20 m. Notice that the difference between 80 mW and 360 mW is just ONE S-point. 4x is 6 dB is one S-point.
By comparing the info in both tables, you can find out, on what band each DXCC was worked.
21 out of 28 QSO's were more than 1000 Miles per Watt QSO's. This is a staggering 75%.

QRPp How is it possible

When I started as a HAM, 20 years ago, I used my homebrew transceiver HM7, from Solid State Design, page 214...218, with an Inverted Vee, to work many different DXCC countries in Europe in CW. Because my power was only 500 mW, I had to look for stations, that I received with 599 or more, so the other station could hear my QRPp signal of 500 mW.
During daylight hours my RST would be 559, or even lower.
Please notice that a power of 500 mW is only four S-points weaker than 100 Watts.
See the PA1B QRPp page.

D and E layer
The radio wave is not attenuated when it is reflected by the E-layer. (Total reflection) But during daytime the signal is attenuated by the D-layer, when it passes through the D-layer.

During daylight hours, the signals are attenuated by the D-layer, which is absorbing

I discovered, that when darkness fell, the signals from the south of Europe would be very loud. So this made it easy, to make QSO's over a distance of 1000 km or more. When the D-layer disappears during the night, the signal can reach the the E-layer without attenuation in the D-layer.

The E-layer reflects the signal without attenuation

When the D-layer disappears, there is no attenuation in the radio path. The signal is reflected by the E-layer without attenuation. The attenuation of this sky wave is (only) 6 dB for a doubling of the distance. So the signal will be very strong.
At first, I did not realize, that my own QRPp signal, could also be an earsplitting 599, until I got genuine report from Italy, that my signal was S9, while using just 500 mW.

How low can you go

I was wondering, what the lowest possible power would be, if I would reduce my power in that situation with this excellent propagation.

If I reduced my power, so my RST would be 559, the difference is 4 S-point. This is a reduction in power of 4 x 6 dB = 24 dB which is 4 x 4 x 4 x 4 = 256.
So I could reduce the the power from 500 mW to about 2 milliwatts.

I was surprised by the low value, that I calculated, but this value is very realistic.
From 2001 on, I made many CW contest QSO's over more than 1000 Miles with 2.5 mW and 5 mW,
using PA1B homebrew attenuators.

I discovered that the frequency must be absolutely clear, when you use very low power.

CQ WW DX CW 2011

I started Saturday morning at 0015 UTC and stayed on until 0140 UTC, to make 18 QSO's on 80 meters. It was terrible. I felt it for a few days and the next day I could not wake up. I should have gone to sleep before midnight, to start early Saturday morning.

On Saturday the 26th, I went back on the air, as late as 1100 UTC, to find good propagation on 21 MHz. I used the Lowest Possible Power in each QSO, with a power of 18 mW to 800 mW, with stations in Europe and later in North America. (See table 21MHZ 26th).
At first I used 360 mW, but later the S-meter went up and I was very pleased to work N2NT and VO1TA, with a QRPpp power of 80 mW.
I also made a few QSO's on 28 MHz.

When 21 MHz and 28 MHz closed, I went to 14 MHz, to make a few QSO's with 80 mW to 800 mW and then continued on 3.5 MHz. Most of the time, I use the maximum power of 2.7 watts on this band.
On Sunday morning I continued on this band and even made a QSO with KC1XX. The propagation on 7 MHz was bad, so all QSO's with Europe were made with full power. A few years ago it was possible to make QSO's with 100 mW or even less, on this band. After half an hour, I switch to 14 MHz, to work stations from Europe and a few stations from north America. Over time the propagation got better, so I could reduce the power gradually.
Later in the afternoon I shifted the emphasis from the Lowest Possible Power to the highest QSO rate.

On Saturday I had to glue myself to my chair. Many times I walked out of the the shack to go down stairs after a few QSO's. On Sunday I could stay on the air for long periods of time.

QSO's per continent

After making this analysis per continent, I realized that all QSO's to North America, South America and Asia are more then 1000 Miles per Watt QSO's.
A quick count revealled another 70 "1000 MPW"

QSO's in Europe, so I estimate that the total of 1000 MPW QSO's will be around 170.
Since I did not use the lowest possible power in each QSO this number would be lower, if my FT-817 could give 5 watts, instead of the current maximum of 2.7 watts. hi

Other 1000 Miles per Watt hunters
It is great to see, that other Bloggers also have used QRPp in the CQ WW DX CW contest. More FUN with lower power.
Steve MW0BBU hunted for new DXCC entities with just 500 mW. Click here to visit the QRP Pembrokeshire Blog. Steve noted in the Blog that he noticed that despite the low power, his call was copied immediately correct. hi
Mike VE3WDM also used 500 mW with an indoor attic fan dipole. Click here to check out the list of 1000 MPW QSO's, made with 500 mW.
Well done, gentlemen.

9H1XT in LZ DX with 3.6 mW

The propagation on 10 m is getting very good. Earlier this morning the signals were S9 in the LZ DX contest. When I came back on 10 m, the signal of 9H1XT was S9 + 20 dB and sounded very strong. I repeatedly used 3.6 mW to answer. I had to force myself NOT to increase the power, every time John did not hear me, but answered an other stations. After 7 or more times my perseverance payed off and the QSO was made with 3.6 mW. Tnx John.
It is a long time ago that a power of 5 mW or less could be used. This reminds me of the propagation in 2001, when I could frequently work over thousand miles with 2.5 mW or 5 mW.

OK-OM DX Contest

Last weekend I participated in the OK-OM DX contest. Saturday I started on 80 m and made 23 QSO with 2.7 W. Sunday morning I made just more than 10 QSO's on 40 m. The propagation was disappointing on 40 m. Often I can use just 80 mW on 40m in the morning. But in nearly all the QSO's, I had to use 2.7 W. Only one QSO could be made with 360 mW.

Then I went to 20 m. It was fabulous. I started with 360 mW and later I could reduce to 8 mW in a QSO with OM3IAG. The stronger the received signal, the further the power can be reduced.
I received OL2W and OK7T with 20 dB over S9. This is S9 through the 20 dB attenuator. I noticed that OL2W and OK7T are great listeners with Excellent Ears and both really took the time to answer my 8 mW signal.

The frequency must be absolutely clear, when I answer with this low power. I was hunting for OM3RRC, calling him more then 10 times in vane. Suddenly I was the only caller and he immediately answered to my 36 mW signal. hi

NAQCC 1000 Miles per Watt Award

For years I am a member of the NAQCC. (#2038) The NAQCC club activities are dedicated to QRP and QRPp operation, using CW. When I visited the Award page in August 2011, I got excited by the extensive Award program for QRP and QRPp. Over the years I have made hundreds of confirmed QSO's with more than 1000 Miles per Watt, but untill now, I had not yet applied for an award.
So I decided to apply for the 1000 MPW Award. I choose to apply for the QSO with the highes Miles per Watt. This QSO with RT6A was made in the Russian DX contest in August 2007. A few days later, I recieved the beautifull NAQCC Simple wire antena 1000 Milies per Watt Award, sent by e-mail, from the Award manager, Rick AA4W.

NAQCC Awards Manager, Rick AA4W wrote in the NAQCC Newsletter 153:
Bert, PA1B (NAQCC # 2038), claimed our most popular award in August. The 1000 Mile Per Watt award. But Bert didn't stop at 1000 miles/watt or even 3000 miles/watt, he worked RT6A, from his home in the Netherlands, at a distance of 1584 miles while transmitting .000085 watts (0.85 mW). This calculates to 1,863,803 miles/watt! And he has the QSL card to confirm the contact. Bert has been experimenting and operating at the Milliwatt level for quite a few years. His motto is: "As the S-meter goes up, my power goes down". He uses step attenuators on the output of his Yaesu FT-817 transceiver to give him accurate stepped outputs from 5 watts down to 5 mW. His web page http://a29.veron.nl/pa1b-07.htm tells a wonderful story of his exploits at the Milliwatt power level and he has loads of information about his homebrew attenuators at http://a29.veron.nl/pa1b.htm.
Bert has set the bar for any of us to try some Milliwatt operating.

Ukrainian DX 2011

I had great fun in the Ukrainian DX contest with low power. The 20 m, 15 m and 10 m bands were doing very well. I used a power of 2.7 W down to 36 mW and an Inverted Vee. I used the lowest possible power in each QSO.
I love these DX contests, in which I can work any station that I want.

I found out that 20 meters is still the best band for milliwatting.