Best wishes for 2017

Best wishes for 2017

Best wishes for 2017

Blik over het weiland naast de oprijlaan naar Rhijnauwen. 

Door de mist heeft landschap een sprookjesachtige aanblik gekregen.

De dooi had al ingezet, waardoor het onder de bomen zeer licht leek te sneeuwen.

De bomen zelf waren nog steeds prachtig wit.

Weiland bij Amelisweerd

Koetshuis Rhijnauwen

Cylinder dipole in CQ magazine

Cylinder dipole in
CQ Magazine

In the CQ WW WPX CW contest 2016 I used two indoor cylinder dipoles. After I sent in my log for the CQ WPX, Terry N4TZ noticed my soapbox. Terry asked my to send in a picture of my cylinder dipole to include in the write up of CQ Magazine. I thank Terry for the nice and beautiful write up.

Click to read

The CQ WW contests generate a lot of activity.
I use contests to make QSO's with very low power.
And. . it is good opportunity to test your antennas.


Soapbox PA1B in CQ WW WPX CW 2016
X-RADIOS:           FT-817
X-ANTENNAS:    Cylinder dipole
SOAPBOX:            I had great fun with QRP and two cylinder dipoles
SOAPBOX:           On 20m I made 3 QSO's and on 15m 4 QSO's with a 15" cylinder dipole 
SOAPBOX:           On 40m I made 3 QSO's with a 22" cylinder dipole 
SOAPBOX:           The PA1B cylinder dipole consists of two cylinders and a coil
SOAPBOX:           The coil acts as a impedance transformer
SOAPBOX:           The QSB and the good activity, did not make it easy to answer CQ's - hi
SOAPBOX:           Thanks for the activity in the contest

PA1B with cylinder dipole in CQ Magazine

The cylinder dipole shows a large capacity between the cylinders.
Although the coil and the capacity  are tuned to the band of interest, the cylinder dipole can be used as a multi-band antenna. Two taps at the center of the coil provide a low impedance feeding point to connect the twin lead.  Match for a SWR of 1:1 with your symmetrical tuner.

  Energy  Booster  cans or not, a cylinder dipole will radiate better than a wire dipole of the same length.

Thank you, Terry for the very nice write up. 

36dB Attenuator for 20 W by PH2LB

This beautiful attenuator is designed and built by Lex PH2LB.

0...36 dB attenuator built by PH2LB  -  Click to enlarge the pictures

Power
The attenuator can handle a maximum power of 20 watt.
At first I did not realized why Lex designed the attenuator for 20 W. Like many HAMs I thought, that 20 W is QRO. But please notice that 20 W is the Maximum power.  The chosen maximum power of 20 watts for the attenuator is an excellent choice. The attenuator can easily handle a power of 5 watts, without getting hot. The nominal power of the attenuator is 5 Watt.

This was an eye-opener for me. hi.

0...36 dB attenuator by PH2LB
with 2 W resistors 

Derating
A resistor that  dissipates its maximum power will get very hot.
So it is good practice to choose the maximum power 4 times higher then the continuous power.
Lex choose for  a maximum power of 20 watts, to reduce a power of 5 watts.
The resistors have a maximum power of 2 watts. With a power of 1/4 of the maximum power, the resistors will dissipate about 500 mW each and they will get warm, but they will not get hot.

The 20 dB section

Visit the article on the 36 dB attenuator on the web site of Lex PH2LB.

PA1B Power Attenuator Calculator
Lex used the PA1B Power Attenuator Calculator to design his 36 dB attenuator for 20 watts.
This unique spreadsheet in Excel calculates the number of resistors and the values of the resistors from the E12-series for an attenuator section.

In the picture below I show the input values for the section of 20 dB, for a maximum power of 20 watts, that is built with resistors of 2 watts.

PA1B Power Attenuator Calculator - Input values for the 20 dB section

Just download the PA1B Power Attenuator Calculator and play with the values. The calculator has no restriction on the power.

Meeting Lex PH2LB

Lex - PH2LB

Last week I visited the HAM convention 2016 - Dag voor de Radioamateur 2016 in Apeldoorn.
I was very pleased to meet Lex PH2LH.
Lex has designed a 0 - 36 dB attenuator for 20 watts, using the
PA1B Power attenuator calculator.

When I approached the stall of Lex, I immediately recognized the 0 - 36 dB Attenuator that Lex has designed and build.
Further Lex showed the beautiful build OZ2CPU digital RF mW / dBm / mV meter.

OZ2CPU digital RF mW / dBm / mV meter
   and the  0 - 36 dB attenuator

40 dB attenuator built by DK5LH

40 dB attenuator built by DK5LH
Click to enlarge  

I received a very interesting email from Hartmut DK5LH, in which he informed me that he successfully built the
PA1B  40 dB attenuator.    Click for schematic. 
He is very pleased with the excellent accuracy of the attenuator, that makes this attenuator suitable for measuring purposes.

Hartmut uses the attenuator to measure the power of his transmitter (2 watts) with a power meter for -80 dBm to -10 dBm
The attenuator is used to reduce the output power of the set to a value that is less than 0.1 milliwatt. (-10 dBm)

40 dB attenuator with metal film resistors of  2 watt and 600 mW  -  DK5LH  

Resistors
Hartmut has used resistors, that he ordered at the firm Reichelt.   Resistors 2 watts.
In his email Hartmut writes:
Ich habe diese widerstände nicht ausgemessen, sondern einfach so genommen. 
Offensichtlich sind dieses sehr genau. 
which means:
I did not measure the resistors, but just used them. 
Obviously  they are very accurate.

Accuracy
The attenuator is built with good available metal film resistors from the E12-series, with an accuracy of  5%. It shows an  excellent accuracy, because in practice the resistors show a accuracy of 1.5 %, or better.
The picture below shows the excellent accuracy of each of the four attenuator sections.

Hartmut is very pleased with the excellent accuracy of his 40 dB attenuator. His attenuator shows an attenuation of 40,5 dB, with the maximum attenuation, with all sections switched to ON. He has calculated the attenuation with the method of measuring DC voltages.

Thank you, dear Hartmut for emailing the beautiful pictures and additional info.
It's my pleasure to show your beautifully built attenuator.

Aboriginal Art Museum

Klik om te vergroten

Al weer een week geleden zijn Tjeerd PA3GNZ en ik naar het Aboriginal Art Museum in Utrecht geweest. Het museum toont hedendaagse Aboriginal kunst uit Australië. Naast de permanente tentoonstelling zagen wij ook de tentoonstelling Remember Me Stories in print, die liep tot 21september.

In de moderne Aboriginal kunst worden geen afbeeldingen gemaakt van de mythische verhalen, maar hebben kleur, vorm en compositie een belangruike rol.

Kruis arcering
Er zijn natuurlijk vele details te zien in de kunstwerken.
Maar één bijzonder detail is het gebruik van de kruis arcering.
Hier door ontstaat een krachtig beeld.

Twee voorbeelden van kruis arcering

Grafpalen

Door termieten
uitgeholde grafpalen

De moderne grafpalen worden uitgehold met een lange boor.

Centraal museum

In het Centraal Museum in Utrecht bezocht ik, onder andere, een expositie met 4 foto's die genomen zijn van af de Domtoren.
Deze enorme foto's zijn elk opgebouwd uit een 60-tal losse foto's, die gemaakt zijn van af een hoogte van 40 meter, 70 meter en 95 meter.

De foto's zijn heel bijzonder.
Het zijn prachtige compositie foto's, met een enorme diepte.
Vooral van dichtbij zie je een veelheid aan details.

Gedeelte van de begeleidende tekst

Panorama Domtoren van Hans Wildschut

Kanoen naar Rustpunt

Koeien.   Klik om te vergroten

Vandaag zou het erg warm worden, dus ben ik gaan  kanoen i.p.v. fietsen. Bij de brug naar Merwestein, de Doorslagbrug, ben ik gestart. De Doorslag af en dan aan het eind links af, de Kromme IJssel op. Een prachtig, rustig riviertje met aan beide zijde hoge bomen.  In de onderstaande foto linksboven. Onder de bomen was de temperatuur behagelijk.

Op de Kromme IJssel werd ik vergezeld door een ijsvogel. Deze blauwe schicht, leidde mij weg van het nest, door eerst opzichtig op een tak boven het water plaats te nemen en als ik dicht bij kwam zo'n vijftig meter voor mij uit te vliegen. Na 5 keer het zelfde kunstje vertoont te hebben, vloog het vogeltje in een flits het bos in en vermoedelijk terug naar het nest. Fantastisch.

Na het verlaten van het IJsselbos kom je in een mooi, kleinschalig wijde gebied. Foto rechtsboven. Daar voer ik door tot aan de Looije brug. Dit is de naam van de brug en van de boerderij die er naast ligt. Deze boerderij was "Boerderij van het jaar" in 1991. Foto linksonder.

Mijn einddoel was het gezellige  Rustpunt aan de Lage Dijk Zuid(38). Ik heb de kano bij de boerderij laten liggen en ging te voet naar het Rustpunt voor koffie en zelfgemaakte appeltaart. Ook weer fantastisch.

De foto rechtsonder toont het viaducht over de Kromme IJssel onder de drukke A2. Het punt is makkelijk herkenbaar vanaf de A2.

Al met al een heerlijke, zonnige relaxte middag. Bij het bewaren van het evenwicht, gebruik je andere spieren dan bij het fietsen. Dus had ik 's avond natuurlijk wel spierpijn. Er moet dus meer gekanood worden.

Klik om te vergroten

Vanfleteren en Armando

Armando door de lens van
Vanfleteren

Het Museum Oud Amelisweerd is een zeer bijzonder museum en ligt voor mij nog op fietsafstand ook.


De brochure van de huidige tentoonstelling vermeldt:
Voor Stil Leven liet Vanfleteren zich inspireren door de collecties van Museum Oud Amelisweerd. In nieuw fotowerk, dat speciaal voor de tentoonstelling tot stand kwam, treedt Vanfleteren in dialoog met het oeuvre van Armando, het landhuis Oud Amelisweerd en de omringende natuur. De tentoonstelling is een ode aan de stilte; een fotografische reis langs thema’s als schoonheid, melancholie en herinnering.

 Armando - Vanfleteren - Armando     (Click to enlarge)   

De tentoonstelling is zeer smaakvol en met oog voor detail ingericht. In de bovenstaande, door mij gemaakte compositie foto, zie je in de Grote blauwe kamer twee werken van Armando. (links en rechts) en door de deur zie je de onderstaande foto van Vanfleteren. Armando was aangenaam verrast door deze bijzondere opstelling, vertelde Vanfleteren in Kunstuur van de Avro.

Vanfleteren liet zich op zijn beurt weer geinspireren door het werk van Armando en de natuur rond het museum.

De tenstoonstelling loopt nog tot en met 18 september 2016

Jaarmarkt Noordeloos

Zaterdag morgen hadden we eerst regen, maar later brak de zon door. Dus op naar Noordeloos, voor de jaarmarkt.
Het allereerst tentje dat we tegen kwamen, was een tentje met leuk geprijste kleding.

Click

Er tegen over stond de Ambachtelijk Palingrokerij 't Tonnetje uit Wijk en Aalburg. Terwijl mijn vrouw aan het passen was, had ik zéér ruim de tijd om een paar foto'te maken.

Ambachtelijke palingrokerij 't Tonnetje

Er worden zo'n 15 palingen aan een ijzeren pin geprikt en dan worden ze gerookt. Dit gebeurt achter de twee deurtjes van de rookkast. Het handvat, om de deurtjes te sluiten, is loeiheet en wordt met een houtje aangeduwd,

Palingfuik

De fuik zit slim in elkaar. het verticale net zit in het midden van elk van de twee fuiken. Een paling die van de ene kant of de andere kant tegen het verticale net zwemt, eindigt in één van de twee fuiken en uiteindelijk achter de twee deurtjes.

Rustpunt

Gisteren avond scheen na het eten in eens de zon,

Na een middag met wat flinke buien.

Dus ben ik er met de fiets, nog een uurtje op uit geweest.

Op de Lage Dijk-zuid (38) passerde ik een Rustpunt.

Het zag er heel gezellig uit.

Vanmiddag was het mooi fietsweer, dus ben ik langs gefietst.

Het Rustpunt is eenvoudig te vinden.

Bij knooppunt 9 op de Lekdijk ten zuiden van IJsselstein, 

staat het hier  naast afgebeelde bord. Dat wijst in de richting van knoopunt 8.

Via knoopunt 8 bereik je het Rustpunt.

Zoals je op de foto's ziet, is het heel gezellig in gericht.

De koffie is lekker en de appeltaart zeer smakelijk.

Rustpunt.   Klik om te vergroten

Stefano IZ1OQU makes SSB QSO's with 5 mW

Stefano IZ1OQU 5 mW SSB
with light weight VHFantenne

Hi Bert,

One year passed since our last email and now I write to tell you some recent news about my experiences with power attenuators in QRPp.
Last Sunday, during the Italian Apulia Contest VHF on 2 meters, I made 19 QSO's.
11 QSO's were completed with 5 mW, 4 with 50 mW and 4 with 500 mW. 

I never needed to repeat my callsign. No propagation, no e-sporadic: just directs. 

The best QSO was with a French station over 312 km, good for 62.400 kms per watt. 

My operating location was 500 m asl, with good opening to the sea and the French coast. I'm forgetting to say... That it was SSB!

The antenna is a personal design, low weight very easy to use on portable: two rectangles vertically linked to each other, with nice gain and good front/side. You can see it on my qrz.com. But I attach a photo for your comfort.

What an unbelievable experience! The first time with 5 mW drove me crazy. Surely VHF offers big chances to play with micro-powers, thank to big-gain antennas both on tx and rx sides, and global low power absorption. It is a test that I want to repeat as soon as possible, looking for DX.

Every time I think back to the day that I found your website: my life changed and my passion for QRPp now flies on golden wings. Thank you again, my friend.

Best regards

'73 de IZ1OQU Stefano

Tiny frogs

Frog  -  1 cm  -  0,4 inches

Today my wife discovered two cute tiny frogs in the garden in front of the house. They were not able to jump to a height of 6 inches (15 cm) to escape from the tile floor to the actual garden, so they could take cover, under need the plants. So I helped them both a little to reach the garden.

PA1B Attenuator

I developed attenuators that very accurate and fast to operate. In order to get the best power distribution, the attenuator section with the lowest attenuation is placed in front. I use these attenuators in very low power CW QSO's.

PA1B Fast and accurate power attenuator for CW QSO's

Line up of the sections
While testing and making measurements with 5 watts, I noticed that the attenuator section of 20 dB gets warm with in 10 or 20 seconds. So I changed the line up of the sections. By placing the attenuator section of 3 dB  in front, this sections will dissipate half of the input power. This line up and the choice of the attenuation, makes it possible to get an attenuation of 10 dB, with the sections of 3 dB and 7 dB switched ON. An extra 10 dB gives an attenuation of 20 dB.

10 dB = 3 dB + 7 dB 
20 dB = 3 dB + 7 dB + 10 dB

Cylinder dipoles in the UBA CW 2016

In this UBA DX contest I experimented with  the new built Booster cylinder dipole.

Wingspan 55 cm
The Booster antenna is called Booster, because each cylinder is made out of 6 Energy Booster cans, that are cut open and bolted together. The length of the cylinders is 22 cm (9") and the wingspan of the antenna is 55 cm (22")
The booster is hanging in the dormer window at the second floor. The coil is wound on a 110 mm PVC tube and has 15 turns. The Booster resonates on 10 MHz.

The Booster - One cylinder is made of 4 cut open cans - PA1B

It took my a long time to discover the right setting of the tuner for the Booster on 20 m. At first I could not get a good matching at all on 20 m. The SWR was too high. At the end of the contest, I discovered the right setting for the tuner to get a SWR of 1:1  This is the setting that I always use on 10 m, with the inverted Vee. hi.

The Booster - Wing span 22" - PA1B

The table below shows the QSO's in chronological order.

Booster on 20 m 
The table shows that in the first 5 QSO's, I used the Booster on 20 m. The Booster is longer than the Monster, so I expected much of the Booster on 20 m. But I could not get a SWR of 1:1.

Taps at the center  - ONE turn apart - Click to enlarge

Monster (35 cm) on 20 m
After 5 QSO's, I was a bit disappointed. Just to make some QSO's, I decided to switch the shorter Monster energy can antenna, which is located in the the shack, also on 20 m . This antenna is easy to match. I could easily make two QSO's with UA.

Booster on 40 m

On Sunday morning I went to 40 m. I started with the twin lead two turns apart. I ended up with the twin lead connectors ONE turn apart to get a SWR of 1:1 

Monster on 15 m

The monster is doing fine on 15 m. A total of 8 QSO's were made on 15 m. The signals in QSO number 14 were very strong so I reduced to 800 mW.
QSO number 16 was with R0AA over a distance of 5200 km and was very easy to do.
<<  Read the details of the  QSO with R0AA >>  Click

Booster again on 20 m

My experimenting payed off. I found out by desperately playing around with the tuner, that I had to use a very strange setting of the tuner to get a SWR of 1:1   - Finally I got the Booster working on 20 m. With this setting the last two QSO's were easily made. hi.

UBA CW - Booster - Monster - PA1B

Wat een gein

De blikjes komen van de straat. Ik drink het niet zelf.

 Energy Booster  is verkrijgbaar bij Trekpleister voor 39 Eurocent.

Contest QSO's with the cylinder dipole

Is it really THAT simple?

The cylinder dipole has proven to be a indoor HF-antenna with the size of a VHF/UHF-antenna.  The cylinder dipole with Monster energy cans is working fine on 15 m.

Build  - Work  -  Analyse

This table gives an inside on the number of CW contest QSO's that I made with cylinder dipoles per band and per contest. In the table, QSO means a single QSO outside a contest. All QSO's were made with 4 W or less.

Most of the QSO's were made with the cylinder dipole with two Monster cans.
I noticed that there is NO sharp boundary, but the the Monster seem to work better on 21 MHz than on 14 MHz.
It is not easy to compare antennas on different bands or in different contests, because the propagation has much more influence than the used frequency.

Number of QSO's per band with Cylinder Dipoles  -  PA1B

Easy to build indoor antenna

The Monster cylinder dipole, made of two Monster energy cans of 500 ml is a good, easy to build indoor antenna for 15 m, but also works on 10 m and 20 m. If you want to get acquaint with the indoor cylinder dipole, I suggest to build the cylinder dipole with Monster cans and a coil with 9 turns on a coil former of 80 mm. The cylinder dipole is fed on two taps at the center of the coil that are ONE turn apart.

More construction info here Click

Transmission of SAQ

I never heard the transmission of SAQ on 17.2 kHz in CW, my self on the air. So last December I wanted to install my active loop antenna with 12 turns and a the frequency converter to listen, but . . . I was to late. It would take hours to figure out, how to connect the circuits, that were last used, years ago. I thought that I had all day to prepare, on the 24th of December. But when I looked it up, on internet, I noticed that the transmission would start within 15 minutes. hi.

I immediately decided to follow the transmission on internet and I liked it very much. I watched the live stream. The live stream shows what is happening at the machine. You can see the operators in their blue shirts. At 7:47 utc I saw the CW operator take his place behind the key. You could hear that the text  vvv de SAQ now was given by hand. 

When I started to watch there were already 66 persons watching. At the end of the transmission 119 persons were watching.

I sharpened my pencil and wrote down the text. I enjoyed it very much. I like the live stream and just taking the Morse code by hand behind the computer in the shack. hi.

The machine at SAQ      In the shack of PA1B

Thanks to the SAQ team for the interesting transmission.

Up date
SAQ is special station from Sweden which operates on 17.2 kHz. The power is generated by a generator. Please visit www.alexander.n.se for info.

Here is the video of the transmission that I followed.
https://www.youtube.com/watch?v=cMgIFo7SQFU

In the video at 5:40  vvvv vvvv de SAQ SAQ starts, automatically keyed, until 16:53 min.
At 17:00 minutes in the video, the CW operator takes over. 

Cylinder dipole construction

Constructing a cylinder dipole
The cylinder dipole consist of two open aluminium cylinders and a coil. The coil is connected between the cylinders and is hanging below the cylinders. I constructed my first cylinder dipoles from aluminium energy drink cans that I found on the street. To get open cylinders, I remove the top and the bottom of the cans.

Cylinder dipole  -  PA1B

Energy drink cans
The cylinder dipole, that is tuned to 15 m, but also works very good on 10 m, consists of two aluminium energy drink cans of 500 ml. The top and the bottom of the cans were removed. 
The two cylinders form the radiators of the cylinder dipole. The current on the surface of the cylinders, causes the radiation.
The coil has 9 turns and is wound on a PVC tube with a diameter of 80 mm. The taps are one turn apart. 
I have a lot of fun with this cylinder dipole in the shack at the first floor, 4 meter above the ground. This cylinder dipole can also be used on 20 m, with lower efficiency.

Parallel resonance
The cylinders show a large self capacity. This capacity is much larger than the capacity of a wire of the same length as the cans. The capacity of the cylinders and the induction of the coil form a parallel LC resonant circuit. The impedance of this LC circuit is high at resonance. 
Please notice, that this parallel resonance, is what makes the difference between the cylinder dipole and a dipole with very short wires.

Tuning
The cylinder dipole is tuned by choosing the number of turns of the coil.

Feed point
I made taps, at the center of the coil. The connection on the taps of the coil, form a feed point with low impedance, to which the 300 ohm twin lead is connected. The lower the number of turns between the taps, the lower the impedance will be. I had good results with the taps just ONE turn apart. 
Please notice, that because the taps are placed at center the coil, the ribbon will not radiate it self.

Matching
The cylinder dipole is matched (not tuned) by the symmetrical tuner in the shack. The tuner is adjusted to the lowest SWR. 

Multi band antenna
The cylinder dipole can be used as a multi band antenna, simply by matching the antenna to a SWR of 1:1 on the band that you want to use. That's all. 

Build - Work - Analyse 
I am curious about your results.

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.

Quite a distance

The 15" cylinder dipole amazes me time and time again.

Today I was surprised by the cylinder dipole that is made of two  Monster  energy  cans  and a coil that hangs inside the shack, on the first floor. This antenna with a length of 15 inches, has proven before, that it is doing fine on 21 MHz. After a number of QSOs's with Russia and the Ukrain, I made a QSO deep in to Russia.

An hour before the end of the UBA DX contest, I met Alexander R0AA from Atsjinsk. (Ачинск) My paper notes states that the QSO was easy. (makkelijk). This was QSO number 16 in the contest.

Later I realized that R0 must be deep in to Russia. On the map I saw that Atsjinsk lays east of Kazakhstan and north of Mongolia. hi. The distance is 5223 km or 3245 Miles. WOW.

R0AA - PA1B - 5223 km  - Cylinder dipole 15" - 4 watts 

One coil and Two Monster cans
Really amazing. HI.

140 QSO's with the cylinder dipole

Since the ARI contest in May 2015, I made 140 QSO's with 3 types of cylinder dipoles. The table shows the 3 different cylinder dipoles that I used, in several contest in 2015 and 2016.

Build  - Work - Analyse

I made this table to show the number of QSO's, that were made, with each of the three types of cylinder dipoles that I have build.

Number of QSO's with different Cylinder Dipoles - PA1B

I used the Red Bull antenna in the ARI contest on 20 m and 40 m. At that moment 15 m and 10 m showed no activity. But the propagation on 20 m and 40 m  was excellent.
The 6 QSO's on 10 m were made in two different 10 m contests.

The Monster antenna, made of two Monster cans of 500 ml is an excellent, easy to build indoor antenna for 15 m, but also works on 20 m. The table show that it works better on 15 m that on 20 m.

The Booster with it's wingspan of 55 cm (22") is build for 20 m and 30 m and is until now, only used in the PACC.
In the PACC I made 27 QSO's on 40 m. The Booster works on 40 m and 20 m. In the PACC there was more activity on 40 m than on 20 m. But I suspect that the booster works best on 20 m,

The used the cylinder dipoles indoor from the shack or from a dormer window at the second floor, with a power of 4 W or less.