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Sunday, March 17, 2013
A Beautiful Workshop in Scotland
A nasty Coronal Mass Ejection hit our magnetic field at around 0600 UTC today. The HF bands are now in poor shape. What better time to visit a really impressive workshop in Scotland?
Ian has an interesting site: http://www.ianjohnston.com/
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Saturday, March 16, 2013
Vanguard!
Wow, Vanguard even looks like a QRPp satellite.
I suspected that something was up: I noticed that Mike Rainey, AA1TJ has recently been crossing pond with a QRPp Germanium rig... Then Steve "Snort Rosin" Smith clued me in: The next period of Vanguard QRPp Activity Days begins tomorrow. "Club 72" has a nice write up, and a nice collection of pictures of the Vanguard rigs that have been built around the world:
http://www.club72.su/vanguard.html
Go Germanium! Go Vanguard!
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QRP SSB with a New Rig
Kelly, WB0WQS, was trying out a new KX3 that his wife had given him as a present. The radio gods must like that low-power rig because, in what seems like a deliberate demonstration of the awesome power of QRP phone, Kelly's first QSO was with another QRP operator: me! The sun was going down and taking 17 meters with it, but neither of us missed a word. We talked about SolderSmoke and our mutual friend, Jerry, NR5A -- Kelly had known Jerry when they were teenage hams. Good luck with the new rig Kelly!
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Friday, March 15, 2013
Kludge: Rube-Goldberg Heath-Robinson Ad-Hockery
Wow! "Ad-hockery... verging on being a crock." That sounds like my building technique! I thank Kevin for sending this, but I admit to now being more confused than ever.
Bill:
A snippet from my kluge research. This was a word I learned from my dad who told me he had heard it first used in the 1930s. Here is where I find a divergent meaning with the new word kludge which I have often heard pronounced as rhyming with sludge. I was asked why I pronounced it with the d as silent. I asked why I should pronounce a letter which was not even in the word. Thus my introduction to the new word kludge which means something very different than what I had learned from my father. While a kluge is something clever a kludge is an ad hoc and usually buggy hack.
I found a little supporting evidence for the etymological timeline. To whit:
Source: The Free On-line Dictionary of Computing
(2003-OCT-10)
kluge
The spelling
"kluge" (as opposed to "kludge") was used in
connection with
computers as far back as the mid-1950s and, at
that time, was used
exclusively of *hardware* kluges.
2. A clever programming trick intended to solve
a particular nasty
case in an expedient, if not clear, manner.
defined
"kludge" as "a crock that works".
3. Something that
works for the wrong reason.
In 1947, the
"New York Folklore Quarterly" reported a classic
shaggy-dog story
"Murgatroyd the Kluge Maker" then current in
the Armed Forces,
in which a "kluge" was a complex and
puzzling artifact
with a trivial function. Other sources
report that
"kluge" was common Navy slang in the WWII era for
any piece of
electronics that worked well on shore but
consistently failed
at sea.
However, there is
reason to believe this slang use may be a
decade older. Several respondents have connected it to the
brand name of a
device called a "Kluge paper feeder" dating
back at least to
1935, an adjunct to mechanical printing
presses. The Kluge feeder was designed before small,
cheap
electric motors and
control electronics; it relied on a
fiendishly complex
assortment of cams, belts, and linkages to
both power and
synchronise all its operations from one motive
driveshaft. It was accordingly tempermental, subject to
frequent
breakdowns, and devilishly difficult to repair - but
oh, so clever! One traditional folk etymology of
"klugen"
makes it the name
of a design engineer; in fact, "Kluge" is a
surname in German,
and the designer of the Kluge feeder may
well have been the
man behind this myth.
have developed in a
milieu that remembered and still used some
"kluge"
came to MIT via alumni of the many military
electronics
projects run in Cambridge during the war (many in
building was demolished
in 1999).
Source: Jargon File (4.3.1, 29 Jun 2001)
kluge /klooj/ [from the German `klug', clever; poss. related
to Polish
'klucz' (a key, a
hint, a main point)] 1. n. A Rube Goldberg (or Heath
Robinson) device,
whether in hardware or software. 2. n. A clever
programming trick intended to solve a particular nasty case in an
expedient, if not clear, manner. Often used to repair bugs. Often
programming trick intended to solve a particular nasty case in an
expedient, if not clear, manner. Often used to repair bugs. Often
involves ad-hockery
and verges on being a crock. 3. n. Something
that works for the
wrong reason. 4. vt. To insert a kluge into a
program. "I've
kluged this routine to get around that weird bug, but
there's probably a
better way." 5. [WPI] n. A feature that is
implemented in a
rude manner.
Nowadays this term
is often encountered in the variant spelling
`kludge'. Reports
from old farts are consistent that `kluge' was the
original spelling,
reported around computers as far back as the
mid-1950s and, at
that time, used exclusively of _hardware_ kluges. In
1947, the "New
York Folklore Quarterly" reported a classic shaggy-dog
story `Murgatroyd
the Kluge Maker' then current in the Armed Forces, in
which a `kluge' was
a complex and puzzling artifact with a trivial
function. Other
sources report that `kluge' was common Navy slang in the
WWII era for any
piece of electronics that worked well on shore but
consistently failed
at sea.
However, there is
reason to believe this slang use may be a decade
older. Several
respondents have connected it to the brand name of a
device called a
"Kluge paper feeder", an adjunct to mechanical printing
presses. Legend has
it that the Kluge feeder was designed before small,
cheap electric
motors and control electronics; it relied on a fiendishly
complex assortment of cams, belts, and linkages to both power and
complex assortment of cams, belts, and linkages to both power and
synchronize all its
operations from one motive driveshaft. It was
accordingly
temperamental, subject to frequent breakdowns, and
devilishly difficult
to repair -- but oh, so clever! People who tell
this story also aver
that `Kluge' was the name of a design engineer.
There is in fact a
Brandtjen & Kluge Inc., an old family business that
manufactures
printing equipment - interestingly, their name is
pronounced
/kloo'gee/! Henry Brandtjen, president of the firm, told me
(ESR, 1994) that his
company was co-founded by his father and an
engineer named Kluge
/kloo'gee/, who built and co-designed the original
Kluge automatic
feeder in 1919. Mr. Brandtjen claims, however, that this
was a _simple_
device (with only four cams); he says he has no idea how
the myth of its
complexity took hold. Other correspondents differ with
Mr. Brandtjen's history of the device and his allegation that it was a
Mr. Brandtjen's history of the device and his allegation that it was a
simple rather than
complex one, but agree that the Kluge automatic
feeder was the most
likely source of the folklore.
TMRC and the MIT
hacker culture of the early '60s seems to have
developed in a
milieu that remembered and still used some WWII military
slang (see also
foobar). It seems likely that `kluge' came to MIT via
alumni of the many
military electronics projects that had been located
in Cambridge (many
in MIT's venerable Building 20, in which TMRC is
also located) during
the war.
article mentioned above; it was titled
"How to Design a Kludge"
(February 1962, pp.
30, 31). This spelling was probably imported from
Great Britain, where
kludge has an independent history (though this
fact was largely
unknown to hackers on either side of the Atlantic
before a mid-1993
debate in the Usenet group alt.folklore.computers over
the First and Second
Edition versions of this entry; everybody used to
think kludge was
just a mutation of kluge). It now appears that the
British, having forgotten
the etymology of their own `kludge' when
`kluge' crossed the
Atlantic, repaid the U.S. by lobbing the `kludge'
orthography in the
other direction and confusing their American cousins'
spelling!
The result of this
history is a tangle. Many younger U.S. hackers
pronounce the word
as /klooj/ but spell it, incorrectly for its meaning
and pronunciation,
as `kludge'. (Phonetically, consider huge, refuge,
centrifuge, and
deluge as opposed to sludge, judge, budge, and fudge.
Whatever its failings
in other areas, English spelling is perfectly
consistent about
this distinction.) British hackers mostly learned
/kluhj/ orally, use
it in a restricted negative sense and are at least
consistent. European
hackers have mostly learned the word from written
American sources and
tend to pronounce it /kluhj/ but use the wider
American meaning!
Some observers
consider this mess appropriate in view of the word's
meaning.
I hope this further muddies the definitional waters for you
:)
73,
Kevin. KD5ONSOur book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Thursday, March 14, 2013
Almost forgot! Happy Pi Day!
3-14 Get it?
And happy birthday Albert Einstein!
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
Einstein -- Albert,
mathematics
Autographed SolderSmoke Books
I have some books left over from Winterfest. Please let me know if you'd like a signed copy. Some folks are ordering them as gifts for fellow Knack victims. I will inscribe them with whatever you'd like me to write (within limits, of course!)
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
book
Wednesday, March 13, 2013
The Overview Effect
OVERVIEW from Planetary Collective on Vimeo.
Every once in a while, it's a good idea to step back and consider the big picture.
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
space program,
video
Tuesday, March 12, 2013
Fabio's Direct Conversion Receiver
Fabio, IK0IXI, is an electronic wizard from Civitavecchia, near Rome. Check out his very nice DC receiver. Note that wonderful direct conversion sound. Very cool that has it atop our beloved SPRAT. Below you can hear the effectiveness of the audio filter. Bravo Fabio!
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
direct conversion,
Italy,
SPRAT
Sunday, March 10, 2013
A Ham Radio HackerSpace
Bill - Enjoyed your conversation regarding seeing the Maker guys at a recent hamfest. Thought I'd let you know that, at least on a small scale, we've created a ham hacker space in our club by organizing a "Builders Group" as an adjunct to the Williamsburg Amateur Radio Club (WAARC) here in Williamsburg, VA. I volunteered my QTH as a meeting place and the majority of projects have been either QRP or test equipment related. Folks select their own project and bring their own tools to use. These projects have included the Hendricks tri-band QRP transceiver, NorCal FCC-1 frequency counter, N3ZI digital dial, Tuna Tin II transmitter and others.
I corralled two friends in the club to act as "mentors" to assist less experienced builders with soldering and construction. Once builders complete their projects my workbench upstairs is available to verify correct operation or troubleshooting as required.
Here are a couple of pix of the guys having fun melting solder.
73 - Dino KL0S
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Saturday, March 9, 2013
Richard's Rip-Van-Winkle Barbados Rig
Dear Bill,
Thank you for taking a few minutes to read my email. I recently found your blog and enjoyed reading the entries. However, the most interesting and exciting article I discovered was your "Homebrew Radios in the Age of the Internet." The article reminded me of a project started 30 years ago this month and placed in a box in the attic to wait until I could return to it.
Thirty years of health care management work filled the interim.
The project is the 8P6 Hamcation rig by W1FB from QST of June and November 1982!
I searched through the cob webs in the attic and found that all the boards are completed and I even fabricated a case. The original QST's were there too! In response to a (somewhat strong) suggestion from my wife to "get a winter project going", the rig is back on my retirement work bench. Wahoo.
Progress to date has been instructive and fun. The boards are all cleaned, checked, and 95% wired together in the case and working. I attached 2 photo for your pleasure because you wrote specifically about the receiver in some blog posts.
This is where I am scratching my head. As you say in the article, "receivers are tough". I am confused and a bit frustrated about the correct procedure and sequence to correctly align the Barebones superhet. I can already hear stations and the noise level is acceptable. But I am not quite sure how to proceed in peaking up the receiver (hit a plateau?) Any suggestions for a newly retired ham now with the time to get back to the bench?
Thank you very much for your kind comments and interest in my project.
73's
Richard
WB2PEF
Cherry Valley NY
Wow, what a cool resurrection project! I recognize both the receiver and transmitter boards. The RX is clearly DeMaw's Barebones Superhet on a FAR Circuit board. I am listening to one of those AS I TYPE. Mine was put together by Dale, W4OP, and currently inhales on 17 meters. The TX board is what became known as the VXO 6 Watter. It was (I think) designed by W1VD, and appears in the ARRL book "QRP Classics." This was my first really successful homebrew rig -- I built that transmitter in the Dominican Republic in 1993. I still have most of the board, and the 20 meter Barebones RX that I used with it. Richard's message makes me want to put this old gear back on the air.
I hope Richard will send us an update on his Barbados revival project.
I'm sure Doug DeMaw would be very pleased to know that his projects are still providing radio amateurs with a lot of fun and inspiration.
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
Barbados,
DeMaw--Doug,
Dominican Republic
Wednesday, March 6, 2013
SolderSmoke Podcast #150
SolderSmoke Podcast #150 is now available:
http://soldersmoke.com/soldersmoke150.mp3March 6, 2013
-- SolderSnow!
-- Winterfest Hamfest report
-- N2CQR WINS ARRL INTERNATIONAL DX DSB CONTEST!!!!
-- Homebrew Direct Conversion RX meets PSK-31 and FLDIGI
-- Kludge Controversy II
-- More Q Killing
-- Fixing up old cassettes
-- Pat Hawker, G3VA, SK
-- Mailbag
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
SolderSmoke Podcast
Tuesday, March 5, 2013
VE7BPO on "Killing Q"
I'm still scratching my head a bit about HOW the resistor prescribed by Edgardo, LU1AR, cured the 250 kHz oscillation problem that was plaguing the JBOT amplifier in my 20 meter DSB rig. Earlier I'd posted an excerpt from a CQ article in which Doug DeMaw talks about swamping and Q killing. Last week I got a very thoughtful e-mail from esteemed homebrewer Todd, VE7BPO. Here is an excerpt :
Thoughts and Considerations
Let’s discuss squashing low frequency oscillations in a QRP transmitter; say at 200 KHz or so. A low value resistor across the coil (12t -- FT37-43) often works well to stop these.
Oscillations come from the transistor: gain versus frequency isn’t linear, nor is impedance at transistor ports. We’ll often add negative feedback and such to stabilize an amplifier towards unconditional status. In my Tx circuit that oscillated, no feedback was applied.
In the case of an inductor wound on a FT37-43 or FT50-43, the Q is already low (say 8- 15 or so). Obviously a resistor in parallel with such a coil is not going to lower Q since Q is already quite low. That R will reduce the inductor impedance and thus may serve to decrease the low frequency gain of the RF amplifier to stop any low frequency oscillations. This might not work so well with a way-high fT transistor where decoupling might be hampered if UHF oscillations are singing.
Doug DeMaw often referred to the parallel resistor as a Q-killer. If we examine the equations describing parallel, or series resonant circuits -- if the Q of a tank is high enough, we can practically ignore the effect of resistance at resonance. Conversely if we add a resistance and make it high enough, we might even obliterate the resonant frequency or “kill the Q”. Engineers have long placed an R into a parallel-tuned circuit to drop Q and stop oscillations — they refer to it as damping. 1 example might be in old TV sets where a variable resistance was added to peaking coils to prevent a tank from ringing at a frequency determined by the coil L and distributed C. This applies to higher Q inductors and not our FT37-43 inductor.
Decoupling
Our teacher, Wes, teaches us in EMRFD that coupling often occurs along the DC power supply lines. Further, he’s taught us to decouple AC by placing high impedance in this path. Often the impedance is a low-pass filter with series element(s) of a high Z and shunt element(s) with a low Z. The filter must present a simple short circuit (or perhaps just a resistance) at low frequency so DC flows to the amplifier.
Final
Oscillations should likely be identified and treated according their frequency. This topic looks advanced and all RLC networks deserve more attention from us.
Todd, VE7BPO --- Feb 27, 2013
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Thoughts and Considerations
Let’s discuss squashing low frequency oscillations in a QRP transmitter; say at 200 KHz or so. A low value resistor across the coil (12t -- FT37-43) often works well to stop these.
Oscillations come from the transistor: gain versus frequency isn’t linear, nor is impedance at transistor ports. We’ll often add negative feedback and such to stabilize an amplifier towards unconditional status. In my Tx circuit that oscillated, no feedback was applied.
In the case of an inductor wound on a FT37-43 or FT50-43, the Q is already low (say 8- 15 or so). Obviously a resistor in parallel with such a coil is not going to lower Q since Q is already quite low. That R will reduce the inductor impedance and thus may serve to decrease the low frequency gain of the RF amplifier to stop any low frequency oscillations. This might not work so well with a way-high fT transistor where decoupling might be hampered if UHF oscillations are singing.
Doug DeMaw often referred to the parallel resistor as a Q-killer. If we examine the equations describing parallel, or series resonant circuits -- if the Q of a tank is high enough, we can practically ignore the effect of resistance at resonance. Conversely if we add a resistance and make it high enough, we might even obliterate the resonant frequency or “kill the Q”. Engineers have long placed an R into a parallel-tuned circuit to drop Q and stop oscillations — they refer to it as damping. 1 example might be in old TV sets where a variable resistance was added to peaking coils to prevent a tank from ringing at a frequency determined by the coil L and distributed C. This applies to higher Q inductors and not our FT37-43 inductor.
Decoupling
Our teacher, Wes, teaches us in EMRFD that coupling often occurs along the DC power supply lines. Further, he’s taught us to decouple AC by placing high impedance in this path. Often the impedance is a low-pass filter with series element(s) of a high Z and shunt element(s) with a low Z. The filter must present a simple short circuit (or perhaps just a resistance) at low frequency so DC flows to the amplifier.
Final
Oscillations should likely be identified and treated according their frequency. This topic looks advanced and all RLC networks deserve more attention from us.
Todd, VE7BPO --- Feb 27, 2013
Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20
Labels:
amplifier theory,
Canada,
DeMaw--Doug,
Hayward--Wes,
troubleshooting
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