Marconi's House in London

In London, the places where famous people lived are marked with Blue Plaques. I knew that Marconi's name was on the list, but I had never actually seen his plaque. When we were up in London last month we were staying in Marconi's old neighbourhood (Bayswater) so and Billy and I decided to take a look. Video by Billy.

This house is mentioned in the book Thunderstruck by Eric Larson and in Peter Jensen's wonderful Early Radio. Marconi lived here as a young man. His mother took him to London in order to get patent protection for his wireless invention. The way in which Marconi's mom watched out for her son's intellectual property rights reminds me of the way Bill Gates' dad watched out for his.

Marconi's arrival in the UK was a bit difficult. British customs officers were apparently very suspicious of the strange device being brought in by the young Italian. One book hinted that they might have thought that Marconi was involved in some plot to kill Queen Victoria. During the inspection serious damage was done to Marconi's rig.

Dover update: Falling from tree, B2 inheritance?, HB variometer

That's me (the new boy in the workshop) at the key of Ian G3ROO's B2 spy set. Beautiful rig. You will all, I'm sure, understand Nigel M0NDE's question to Ian (see below). The Dover variometer project is very interesting (picture at the bottom). Thanks Nigel! (Try to keep Ian at ground level, OK?)

Hi Bill, a Dover construction club update:

Ian was cutting down some trees in the garden this weekend, and took a tumble. As he fell I asked him if I could be left the B2, I can't tell you exactly what he said but you can imagine. Fortunately he was not injured as the ground was soft with all the rain we have had. The B2 remains in the museum for now.

The black hole has taken the variometer from us forever so a new one was made Thursday night at club. You got the blame tonight for anything that was not in its proper place when sought, the new boy in the workshop always takes the blame!

A length of plastic drain pipe was selected. A coil of about ten turns was wound around a large capacitor as a former and tied off with beeswaxed rafia then mounted onto a plastic rod. The plastic rod had a hacksaw slot put in it lengthwise to facilitate the copper wire exiting the plastic pipe. The plastic pipe was drilled and squeezed and the coil inserted into the pipe. The rod was held in place by friction fit brass washers. Two coils were wound around the plastic pipe,in similar directions. The wire is just tensioned by being passed though holes and threaded in and out of the pipe at each end. A plastic screw allows the inner coil to move through just 180 degrees. The first test showed two inductance ranges were possible 6-12 micro Henries and 12 to 21 mH. We will add additional coils up the pipe to give 21 to 30, 30 to 40 etc. A ten meter fishing rod will form the vertical element, with this variometer and switched coils providing the tuning. The experiment continues next Thursday night.

73 de Nigel Evans M0NDE QTH Dover

African WSPRs -- Homebrew, QRP, and International Brotherhood

Jeff, K07M, and others have noticed that the WSPR system's maps show very few stations in Africa. Gernot, OE1IFM, has launched a fascinating project to help fill this WSPR-gap. He has designed and built a stand-alone WSPR transmitter. No computer is required. It is all in two little boxes. It pumps out 1 watt of WSPR signal. And -- get this -- it jumps around from band to band, transmitting a sequence of WSPR signals on all of the HF ham bands. WSPR requires good synchronization. How, you might ask, does Gernot keep these rigs in synch without a computer and without the internet? No problem: He uses time signals from GPS satellites! Bravo Gernot! One of these rigs is currently on the air from Namibia (V53ARC). You can see it in the screen shot above (taken this morning).
Here is Gernot's creation. Isn't that beautiful? Note the "Homebrewed by OE1IFM" markings on the boards. Truly inspiring stuff!
But there's more: A while back we had a blog entry on Jack Dunigan, 5X7JD. Jack is in Uganda, helping kids who are living with AIDS. Today, one of Gernot's WSPR rigs is scheduled to be delivered to Jack. So soon we should be seeing WSPRs out of Uganda.

You guys should check out Gernot's web pages on this project:
http://www.oe1ifm.at/index.php?option=com_content&view=article&id=52&Itemid=53
His site is filled with really interesting technincal info on this amazing rig.

I found this endeavor to be inspiring at many levels: There is obviously a lot of Knack here, and this is a very good example of what the "International Brotherhood of Electronic Wizards" can do.

Book Review (and a price reduction)

Lulu is having a sale this month. Just enter the coupon code IDES at checkout and save 10% on SolderSmoke -- The Book
http://stores.lulu.com/store.php?fAcctID=3999032

Dale, G4IPZ wrote this review of the book:

It's not often that I've come across a book that combines the fun of Amateur radio along with understandable explanations of difficult technical concepts as well as being a damn good read.
This book not only achieves this but does it perfectly.
It's described on the back cover as "... the story of a secret, after-hours life in electronics." Why after hours? Well because the author, Bill Meara (N2CQR, M0HBR, CU2JL) is a diplomat, a consul for the United states of America, having been posted to such diverse locations as Rome, London, Panama, El Salvador, the Dominican republic and many other places.
During his career as a diplomat his hobby of ham radio and in particular QRP and home-brewing has followed him around the world.
He admits that he did take time out for a while on meeting his future wife and then marrying her. Then, as so many of us have done before, he began to be drawn back into the hobby; the warmth of the shack, where on a cold night, he could sit clutching a hot coffee, listening to the bands, talking to friends and surrounded by the smell of solder smoke.
During his years as a diplomat-ham he has spent much of his free time trying to understand some of the whys and wherefores of the circuits he was building, attempting to build and attempting to fault find when they didn't work. And so many of us have been right down that road!
And that explains what this book is; it's a form of diary of Bill's Eureka moments combined with an insight into his travels and life as a diplomat.
The technical range covered is quite large and despite all my years in electronics I found many of his eureka moments clarified some of my ingrained foggier thinking.
For example we all know how mixers work. Or do we? How many of us can actually explain what goes on even in the simplest of two diode balanced mixers? Most of us just accept that, by the black necromancy of radio in which we dabble, fearing the release the magical smoke at the wrong moment, it just mixes and that's that.
But Bill took time to ask, query and eventually, by making notes to himself, come to understand what was going on. And his explanations of mixers and other such subjects are indeed highly illuminating. He explains semiconductor principles (Do you really understand hole flow versus electron flow?). And how about resonant circuits for example? Bill explains these and much more in a refreshing new way along with capacitors, crystals, and a host of other often accepted but often not fully understood truths that we, as amateurs just take for granted.
This is an ongoing life's trip through the hobby which we all share with Bill, and remember that he is not a professional electronics engineer; he is a radio ham who wants to be more than an "appliance operator".
He enjoys tinkering and has stuck with some pieces of equipment for more years than I will mention but it hasn't stopped him working through the satellites and bridging the oceans on less watts than a nightlight.
And as well as his obvious love of his hobby, he introduces us to many of the other amateurs he has met on his travels and at his various postings. He paints a wonderful picture of the people that many of us may get to meet on the air but he's been lucky enough to meet face to face.
And as well as doing all this he also ventured into the world of Pod-casting and blogging, the outputs which has reached thousands world-wide on his SolderSmoke website.
I cannot recommend this book too highly and I found that it was one which I couldn't put down until I'd finished.
Dale Haines G4IPZ

Black Holes in Workshops?

Nigel (M0NDE), Ian (G3ROO), Tony (G4WIF) at Dover CC HQ

When I was out in Dover (UK) last week the fellows in the Dover Construction Club alerted me to a problem that has been affecting their workshop, and that may be causing trouble in yours: black holes. Apparently through some strange quirk of quantum physics, small black holes are sometimes generated in electronics workshops. They cause parts and tools to disappear. The quantum element of all this is readily apparent: only those parts and tools that you REALLY need disappear. If you don't need a particular part or tool, it will not be affected. The guys out in Dover recently lost a variometer this way, and while I was there a telegraph key briefly disappeared into the quantum mist. In a variation of this phenomenon, very small black holes sometimes pop out of the quantum vacuum when small parts are dropped to the floor -- that's why you often can't find them! SMT parts are especially susceptible to this (obviously because some of the damn things are getting down to quantum scale) . I don't really know what can be done to counteract this problem -- if you have any suggestions, please post a comment.

On a related subject, Jim Miller sent us this:

Tools Explained DRILL PRESS : A tall upright machine useful for suddenly snatching flat metal bar stock out of your hands so that it smacks you in the chest and flings your beer across the room, denting the freshly-painted project which you had carefully set in the corner where nothing could get to it. WIRE WHEEL : Cleans paint off bolts and then throws them somewhere under the workbench with the speed of light. Also removes fingerprints and hard-earned calluses from fingers in about the time it takes you to say, "Oh, shit!" SKILL SAW : A portable cutting tool used to make studs too short. PLIERS : Used to round off bolt heads. Sometimes used in the creation of blood-blisters. BELT SANDER : An electric sanding tool commonly used to convert minor touch-up jobs into major refinishing jobs. HACKSAW : One of a family of cutting tools built on the Ouija board principle. It transforms human energy into a crooked, unpredictable motion, and the more you attempt to influence its course, the more dismal your future becomes. VISE-GRIPS : Generally used after pliers to completely round off bolt heads. If nothing else is available, they can also be used to transfer intense welding heat to the palm of your hand. OXYACETYLENE TORCH : Used almost entirely for lighting various flammable objects in your shop on fire. Also handy for igniting the grease inside the wheel hub out of which you want to remove a bearing race. TABLE SAW : A large stationary power tool commonly used to launch wood projectiles for testing wall integrity. HYDRAULIC FLOOR JACK : Used for lowering an automobile to the ground after you have installed your new brake shoes, trapping the jack handle firmly under the bumper. BAND SAW : A large stationary power saw primarily used by most shops to cut good aluminum sheet into smaller pieces that more easily fit into the trash can after you cut on the inside of the line instead of the outside edge. TWO-TON ENGINE HOIST : A tool for testing the maximum tensile strength of everything you forgot to disconnect. PHILLIPS SCREWDRIVER : Normally used to stab the vacuum seals under lids or for opening old-style paper-and-tin oil cans and splashing oil on your shirt; but can also be used, as the name implies, to strip out Phillips screw heads. STRAIGHT SCREWDRIVER : A tool for opening paint cans. Sometimes used to convert common slotted screws into non-removable screws and butchering your palms. PRY BAR : A tool used to crumple the metal surrounding that clip or bracket you needed to remove in order to replace a 50 cent part. HOSE CUTTER : A tool used to make hoses too short. HAMMER : Originally employed as a weapon of war, the hammer nowadays is used as a kind of divining rod to locate the most expensive parts adjacent to the object we are trying to hit. UTILITY KNIFE : Used to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on contents such as seats, vinyl records, liquids in plastic bottles, collector magazines, refund checks, and rubber or plastic parts. Especially useful for slicing work clothes, but only while in use. Son of a bitch TOOL : Any handy tool that you grab and throw across the garage while yelling, "Son of a bitch" at the top of your lungs. It is also, most often, the next tool that you will need. No trees were killed in the sending of this message. However, a large number of electrons were terribly inconvenienced

Mars Express Phobos Fly-by (Wednesday)

The European Space Agency's Mars Express probe will be doing the closest ever approach to the Martian moon Phobos. On Wednesday night the spacecraft will come within 67 km of Phobos. They will use a very cool radio technique to gather data about the internal structure of the object (see below).
Mars Express carried the Beagle II lander to the red planet. I was in the UK when they made that brave attempt to put the probe on the surface, and shared in the disappointment when no signals came back. Later, I had the privilege of meeting Beagle II's creator, Colin Pillinger. Colin gave me signed copies of his wonderful books on Mars.

Here's some more info on Wednesday's fly-by (from ESA):

1 March 2010
ESA’s Mars Express will skim the surface of Mars’ largest moon Phobos on Wednesday evening. Passing by at an altitude of 67 km, precise radio tracking will allow researchers to peer inside the mysterious moon.

Mars Express is currently engaged in a series of 12 flybys of Phobos. At each close pass, different instruments are trained towards the mysterious space rock, gaining new information. The closest flyby will take place on 3 March at 21:55 CET (20:55 GMT).

From close range, Mars Express will be pulled ‘off-course’ by the gravitational field of Phobos. This will amount to no more than a few millimetres every second and will not affect the mission in any way. However, to the tracking teams on Earth, it will allow a unique look inside the moon to see how its mass is distributed throughout.

How will the ground teams make these tremendously sensitive measurements? Ironically, they will turn off all data signals from the spacecraft. The only thing that the ground stations will listen out for is the ‘carrier signal’ – the pure radio signal that is normally modulated to carry data.

	Preparing for closest approach to Phobos

With no data on the carrier signal, the only thing that can modulate the signal is any change in its frequency caused by Phobos tugging the spacecraft. The changes will amount to variations of just one part in a trillion, and are a manifestation of the Doppler effect – the same effect that causes an ambulance siren to change pitch as it zooms past.

After the closest flyby, the work is not over. Mars Express will sweep past Phobos a further seven times before the campaign is complete. In addition to the tracking experiment, known as MaRS for Mars Radio Science, the MARSIS radar has already been probing the subsurface of Phobos with radar beams. “We have performed a preliminary processing of the data and the Phobos signature is evident in almost all the data set,” says Andrea Cicchetti, Italian Institute of Physics of Interplanetary Space, Rome, and one of the MARSIS team.

The MARSIS radar is already taking data

“All the experiments on Mars Express have something to say about Phobos,” says Olivier Witasse, Mars Express Project Scientist, ESA. This is a bonus for science, considering that none of them were originally designed to study Phobos the moon, only Mars the planet. The science results from these flybys are expected in subsequent weeks or months, when the various teams have had time to analyse the data.



All photos from ESA.

SolderSmoke Podcast #122

Bill (N2CQR) and Ian (G3ROO) in Dover, England (with hydrogen balloon spark key)

SolderSmoke!
A SHOW FOR ELECTRONICS HOMEBREWERS!
Listen at: http://www.soldersmoke.com
SolderSmoke #122

Feb 28, 2010
Snow in Rome!
In London: A visit to Marconi's house, Maplins, and Faraday's lab
A visit to the Dover Construction Club
Computer problems resolved
A short period of QRSS, then back to WSPR
Putting the Drake 2-B into WSPR mode
The Rome-Norway WSPR pipeline
Increased solar activity
50 years of SETI with Frank Drake
QQ Review
Work Bench Eye Candy
Movie Review: UP! (Five Soldering Irons)
MAILBAG

KNACK IN THE SHACK: N5ITU

Jeff, N5ITU, clearly has The Knack.

The mug and the bumper sticker are available at the SolderSmoke Cafe Press store: http://www.cafepress.co.uk/SolderSmoke

Jeff is in Texas. We had a feeling that this particular bumper sticker would appeal to those the Lone Star State.

Reverse Polarity Protection -- Words of Wisdom from K7QO

Words of wisdom from Chuck Adams, K7QO:

Wednesday, February 24, 2010 12:11 AM

From:

"chuck adams"

Add sender to Contacts

To:

qrp-l@mailman.qth.net

This posting due to the traffic on the SST reverse
voltage application.

Here is what I do. There is a diode, the 1N5817,
a Schottky Diode. Will take 20V peak reverse voltage,
will handle 1A continuous with 25A surge and has only
a 0.45V forward drop and the reverse current is 500uA.

I put one of this in series with the 12V line input of
every electronic device I build. If the designer used
a 1N4001-7 in series, I replace it.

I am not a fan of the diode across the voltage input
line and having it short out when reverse voltage is
applied. What if the applied voltage is a gel-cell
without a fuse? You blow the diode and you blow the
rig. IMHO is this not an ideal way to do it. Should
be using fuses too, but I don't. Haven't found a way
to use the flat auto fuses with gel-cells in a handy
low-profile way and inexpensive parts. I'd appreciate
the education, if someone has film and photos of great
arrangements.

I buy the diodes from Mouser.Com for about $26 per 250.
For a dime a rig it is a real cheap way to protect your
equipment from yourself and others.

With the limit of 1A at 13.8V, it is well within the
QRP operating limits. And why do you need more than
1A anyway?????? :-) And the low forward voltage
drop means that the finals (which are usually fed
direct from the B+ line anyway) don't lose much
in applied voltage and you get pretty much the
same output as without the diode. And you protect
those expensive parts for a dime. A quarter if you
buy just one diode from Mouser.

Hope this helps. Just the way I do it, and I'm
not always right. But I've only lost a few parts
and that was before I started using 1N5817's on
everything.

The 1N4001 through 1N4007's are fine if you are
feeding 9-12V to a 78L08 regulator.
FYI
chuck
--
chuck adams, k7qo
http://www.k7qo.net/
chuck.adams.k7qo@gmail.com

F8CKH: The Knack, 747s, and Homebrew QRP

Here is some further evidence that The Knack is a global phenomenon. I'm sure our readers will find Antoine's story quite familiar. Looking at his QSL (below) we can see that he has a special reason to be interested in QRP: After a full workday of operating a very high-powered rig (!), a simple little QRP rig must represent an appealing contrast. And even if that 747 is very QRO, I think we will all agree that Antoine has the kind of job that most knack victims dreamed about when they were kids.

Hi Bill,

I have been listening to your podcasts for a while now after I heard about them in one of the Amateur Logic TV shows. I picked up one podcast randomly and I got to say that I really enjoyed the tone and content of your talks. Very informative and interesting. I like also the fact that your amateur radio experience is based on homebrewing and experimenting. Back in 1997, I earned my French amateur radio license at the age of 16 (extra and big CW lover). I have been always amazed by what we could do with very little and go very far. My family is Hamradio friendly: my grandfather was F8KE back in 1930s and he has been around the hobby for most of his life. At 7 or 8 I remember times where we were at his place and I would ask for permission to leave the table early to go upstairs and visit my grandfathers shack. Everything there was homebrew and I was really pleased to see that the magic of Radio was achievable with only few components, homebrew antennas and a bit of luck. He encouraged me to learn the Code and at 12 I was already up to 20 wpm! My dad used to be 6W8FC while he was in the service and he gave me the passion for weak signal and DXing. Technically speaking, I HAD to become a Ham Radio operator.

I am really fascinated by your level of dedication to homebrewing and also that you share that we us, fellow operators addicted to -soldersmoke-. Just like you, I have been all over the place since I am an Airline Pilot qualified on the Airbus and Boeings... UK, New Zealand, US, I got a chance to operate from couple of places and something got the pleasure to be behind the scene and become the reason of a pile up. Operating from down under from Kiwi lands was a wild and exciting experience, indeed!

Finally I am about to move permanently to the US, in Pennsylvania. I applied for a Vanity Callsign (NY3G) and hopefully I will hear from the FCC soon.

I wanted to mention also that I got rid of almost all my regular Yaesu, Kenwood rigs to start from scratch. My project? To design, build, operate an HF station from scratch. No more commercial rigs for me! Well I will try! I am really happy to finally make use of a workbench that I just cleaned at home. I will set up a blogspot account to illustrate my projects... I think that would be great to make QSO with you Bill, sometime!

Thanks again for bringing some much enthusiasm into this fascinating side of Ham Radio, Homebrewing.

Best Regards,

73

Antoine Pierre GAMET F8CKH