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From: John Larkin on 11 Feb 2010 23:43

---

A 955 acorn tube:

ftp://jjlarkin.lmi.net/Acorn.JPG

John

From: Tim Williams on 12 Feb 2010 01:16

---

So? Light it up and get to work! Should be roughly comparable to a 2N5179,
I'd guess.
http://www.mif.pg.gda.pl/homepages/frank/sheets/049/9/955.pdf
Plate resistance is slightly high and Gm noticably low, but capacitance is
quite small and the plate curves look nice (mu and Rp are fairly constant in
the operating range). Offhand, give it a ~20k plate resistor and you'll get
around 7k || 1.4pF = 16.2MHz -3dB point if driven hard (not counting miller
or probe C). Okay, I suppose a 2N5179 will switch faster than that, but in
terms of fundamental performance, once it cuts off at fT, it doesn't really
do anything anymore; with tubes, add some L to cancel the C and you'll get
narrow-band performance for another decade or two.

Funny how tubes do that. BJTs don't, they kind of just stop working, fT
limited by recombination more than circuit parameters. Do FETs do that? I
know power MOSFETs are typically limited by gate spreading resistance (~a
few ohms, so IRF540 stops being practical at ~10MHz). Do JFETs? What's the
step response of a JFET?

Good MOSFETs, too, but they're hard to find. You'd think a few more microns
of sputtered aluminum over the gate connection wouldn't be worth $20 more,
or whatever it is they do with 'em.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms

"John Larkin" <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in message
news:m1n9n5dokeg2obl8vfj99rd0mresa8783f(a)4ax.com...
>
> A 955 acorn tube:
>
> ftp://jjlarkin.lmi.net/Acorn.JPG
>
> John
>
>

From: Greegor on 12 Feb 2010 01:59

---

On Feb 11, 10:43 pm, John Larkin
<jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote:
> A 955 acorn tube:
>
> ftp://jjlarkin.lmi.net/Acorn.JPG
>
> John

http://en.wikipedia.org/wiki/955_acorn_triode

It doesn't say when these were first made or when they stopped making
them.

They use a reference book from 1954 though.

I got some surplus computer boards once in the 1970's
that had some tiny tubes that might have been peanut tubes.
They layed parallel to the G10 epoxy PC board with
a small metal holding clip riveted to the G10.

A lady friend made jewelry using some that were
new and so the glass had no blackening and the
shiney guts were visible.

The first transister oscillator project I built about 1970
(I was 10 or 11) used two old blue CK722's.

I had the specs but had no idea they were
vintage 1955-1957, about 14 years old or
that they were such a historical part.

http://transistorhistory.50webs.com/ck722.jpg

http://spectrum.ieee.org/biomedical/devices/the-irresistible-transistor

The Irresistible Transistor
Fifty years ago this month, a man embraced his inner hobbyist and gave
thousands of engineers their first transistor

Image: Jack Ward

With this ad, Raytheon Co. introduced the CK722 and slightly better
CK721 (less noise, higher gain) in 1953.

BY Harry Goldstein // March 2003

Is it possible to love a transistor? Certainly what Jack Ward feels
for the Raytheon CK722, the first transistor sold to the general
public, goes beyond casual affection. He's collected thousands of
early transistor specimens, including dozens of CK722s. His stately
yellow Victorian home on a quiet, tree-lined street in Brookline,
Mass., has a basement crammed with enough code oscillators, Geiger
counters, radios, hand-wrought circuit boards, transistorized hearing
aids, subminiature vacuum tubes, diodes, resistors, and capacitors to
make any collector of vintage electronic gear drool. He's written one
book about the CK722 and has started another about early transistor
history at RCA. When he's not working as associate director of quality
for the Bedford, Mass., facility of gene-chip maker Affymetrix Inc.,
he's busy maintaining his virtualTransistor Museum on the Web and is
widely acknowledged by fellow collectors as a techno-anthropologist
par excellence .

"My wife's very supportive, and my younger two children think it's
fairly amusing, and probably not a bad way to have a mid-life crisis,"
says Ward of his family's reaction to his passionate pursuit of
transistor history. Far from thinking that his dad's a square, Ward's
oldest son, Nick, who is pursuing a B.A. in physics, is learning a lot
from his old man. "Nick can't believe how fast technology changes and
that the people I talk to have changed the world," adds Ward, who as
curator of the online museum has shifted his focus from collecting
early transistors to collecting oral histories from the engineers who
sparked the Semiconductor Era.

For Ward and the CK722, it was love at first sight. The year was 1959:
Fidel Castro had just taken Cuba, John F. Kennedy was campaigning for
U.S. president, Buddy Holly was flying around on what would be his
last tour, and Texas Instruments and Fairchild Semiconductor had both
filed patent applications for something called an integrated circuit.
Recalling himself as a boy of 10 marching into his local radio
distributor and plunking down his allowance for his first transistor,
Ward [ see photo] taps into the same wonder that gripped him when he
laid eyes on the CK722, which Raytheon Co. (Lexington, Mass.) made
available to hobbyists through RadioShack stores starting in March
1953.

"They were probably only a couple bucks at the time, but just the
excitement of actually owning one of these was intense. The package is
quite spectacular, you know, the actual shape of the device and the
color," he says. "The blue ones, for instance, the iridescent blue
color is just gorgeous."

With his new transistor, Ward built a radio, just a simple tuned
circuit with a germanium diode to detect a signal and a CK722 as an
audio amplifier. "I turned it on in my room at night after lights out,
and listened to rock and roll or a baseball game," he says wistfully.
"For sheer excitement, I can't think of a parallel with another thing
in technology. I'm tempted to say the PC, but that doesn't quite
capture it. You see, it's different than that."

Love potion No. 722

Ward wasn't the only boy smitten. Tens of thousands of CK722s were
sold between 1953 and the mid-1960s. The irresistible transistor cast
a spell over even die-hard vacuum tube enthusiasts like Terry Hosking.
By the ripe old age of 12, Hosking, now a senior application and
design engineer with SB Electronics Inc. (Barre, Vt.), had concluded
that vacuum tubes were the only way to go.

"I told some of my relatives that I didn't think that transistors were
going to amount to much," Hosking told me. "A few weeks later, I got a
care package from them with a blue CK722 and a Sylvania 2N35
transistor and a couple books that showed how to hook them up. I was
amazed to find that the transistor radio I built would pick up the
local stations without an external antenna and ground like I had to
use with the tube radio."

Transistors weren't just sensitive devices, they were the mysterious
oracles of a new age—"Just a little solid block of black plastic with
three thin wires sticking out," says Tom Lee, associate professor of
electrical engineering at Stanford University. Lee started fooling
around with transistors when he was only five. At that time, in the
mid-1960s, RadioShack sold "blister packs" of five transistors for a
dollar. "They were the only transistors a kid could easily obtain with
saved-up pocket change," he says. "The CK722 is the first recollection
I have of that transistor type, indeed, of any transistor type at all.
The things seemed magical."

And messy in a way tinkerers love. Junior engineers constructing
projects out of transistors and circuit boards had to hone basic shop
skills: measuring, cutting, drilling, and assembly. "Of course, the
most important skill to master was soldering," says Bob McGarrah, now
staff system planning engineer at Central Illinois Light Co. (Peoria,
Ill.).

What madeleines were to Proust, solder is to McGarrah. "The unique
smell of the hot flux still brings back happy memories," he says, one
of which is a of small audio amplifier that he discovered had an
impedance high enough not to draw a dial tone when connected to a
telephone line. A huge fan of the TV spy drama "The Man from
U.N.C.L.E.," young McGarrah used the amplifier to practice his
surveillance skills by listening in on family members' phone calls.

Connecting on the Internet

Like old high school chums who reunite on Classmates.com and realize
that they shared a crush on the same girl way back when, Hosking, Lee,
Ward, McGarrah, and dozens of others linked up on the online auction
site eBay in the late 1990s and began swapping stories along with
vintage transistors.

"Old transistor collectors tend to be a small, close-knit bunch," says
McGarrah, who runs his own transistor history Web site. "The power of
the Internet to bring together such a narrowly focused group of
hobbyists is amazing."

Ward concurs: "Without the Internet, none of this interaction would
really be possible." Inspired by the online communities he saw
sprouting up around vacuum tubes, Ward decided to use the Internet to
research the history of early transistor radios. He soon became more
interested in radio components than the radios themselves, "in how
these little devices were developed, and what a profound impact they
had on society."

In 1999, Ward scratched an itch to write and took as his subject his
first transistor. He began working on The Story of the CK722, and put
up the http://www.ck722.com Web site. Here he posted the fruits of his
research—pictures of the CK722 and other early Raytheon transistors,
charting the 722 through its three case colors, silver, black, and
that iridescent blue [see " Transistor Family Tree,"]. He also posted
pictures of old ads, circuit schematics, packages, and devices people
made with the CK722 that they sent him for his growing collection.

Deep into his yearlong project, Ward attended the Cambridge-based
Massachusetts Institute of Technology's (MIT's) monthly hamfest, a
flea market for the "geek to the max," as he puts it. He made known to
fellow collectors his eagerness to find out more about the origins of
his favorite transistor. "Someone mentioned that they thought Raytheon
had a historian," Ward remembers. "So I called up Raytheon, and sure
enough, there was one. A gentleman named Norman Krim."

Krim's tale

It turns out that 89-year-old Norm Krim is not only Raytheon's
archivist, he's a living link to the roots of the electronics
industry. He's also the father of the CK722 [see photo].


Photo: LARRY VOLK


Norman Krim, father of the CK722 that Jack Ward bought as a child, is
now curator of the Raytheon archives. Here he sits at his kitchen
table and plays with a CK722 radio made and presented to him by Ward.
Late one chilly night this past October, as he and I sat in the
kitchen of his Newton, Mass., home sipping green tea and munching on
roasted almonds, Krim spun his story. Having been a student of
Raytheon founder Vannevar Bush at MIT, Krim took a job with his
mentor's company as an engineer in the receiving tube division in
1935. By 1938, Krim had developed subminiature tubes for hearing aids.

The expertise gained in that work earned six patents on the
subminiature tubes found in the proximity fuses used in U.S. Army
artillery and antiaircraft shells, credited by some historians with
turning around the Battle of the Bulge in late 1944. After the war,
under Krim's steady hand, Raytheon's receiving tube division dominated
the market for hearing-aid tubes with a 90 percent share through the
1940s.

As the industrial war machine was winding down, the semiconductor
revolution was just revving up. At Raytheon's archives in Lexington,
the morning after our late night bull session, Krim showed me a
letter. Dated 9 July 1948, it was addressed to Laurence K. Marshall,
then president of Raytheon, inviting him to Bell Telephone
Laboratories Inc. (Murray Hill, N.J.) to see a demonstration of "a new
device called a Transistor," specifically the point-contact transistor
invented by Walter Brattain, John Bardeen, and William Shockley.
Marshall was busy that day and tapped Krim to go in his place. What he
saw shook him to his very core.

"I was worried that my success had been with tubes, and this was
threatening my job," Krim recalls. "So what the hell was I going to
do? I was going to get into transistors."

Krim's crash program eventually led to the introduction of the world's
first commercially available transistor, the CK703 in 1948, less than
six months after the Murray Hill demonstration.

But the CK703 had some problems. The germanium point-contact transistor
—actually two pointed wires, 125 µm in diameter and 25-50 µm apart, in
contact with the signal-amplifying semiconductor—had to be handmade
with watchmaker precision, which precluded cost-effective mass
production. And they were none too robust. The slightest shock could
ruin them, which made them useless for hearing aids and just about
everything else.

So Krim shifted gears and leveraged his division's growing expertise
in semiconductor technology to make germanium diodes, which had a
ready market as signal detectors in TV sets. By 1950, Raytheon was
cranking out 20 000 diodes a day and Krim was promoted to vice
president of the receiving tube division, where the diodes were being
made.

Double jeopardy

Meanwhile, as germanium diodes and subminiature tubes poured out of
Raytheon's plants, William Shockley was about to jolt the world again,
this time with the junction transistor. Krim was fortunate enough to
room with Shockley for over a week in the spring of 1951, while both
were serving on a military procurement advisory board known as the
Baker Committee.

"Shockley would be proofreading a paper after dinner every night. He
told me, 'I'm going to publish an article in the Physical Review, and
you should remember, pick up that article.' When I got a copy of his
article on junction transistors, that was it for me. The light bulb
went on." And Krim's engineers swung into action.

Their junction transistors were simple devices made of two indium dots
(emitter and collector) alloyed to either side of a germanium chip.
But the germanium wasn't pure enough and the initial devices failed.
Later in 1951, at a symposium conducted by Bell Labs, Krim's team
learned the value of zone refining: passing an RF coil over a quartz
tube containing a large block of germanium crystal and melting
portions of it in sequence. That got the impurities to migrate to the
end of the ingot, which could then be lopped off, leaving a pure
crystal behind.

Knowing that quartz tubes were key to making germanium pure enough for
junction transistors, the crafty Krim cornered the market on quartz
tubing. "And I did one other thing," he says with a sly smile. "There
was a company in Missouri called Eagle-Picher, at the time the
country's biggest zinc refiner. They threw out germanium as a
byproduct of zinc refining. So I bought it all up."

But as Raytheon prepared to introduce its germanium junction
transistor, dubbed the CK718, yields stayed stubbornly low. Water
vapor and other environmental contamination occurring during the
manufacturing process were to blame. To get around the problem, Krim's
team used infant incubators as "clean boxes," so technicians wearing
rubber gloves could reach in and assemble transistors while minimizing
exposure to ambient conditions. Yields went up, and by the end of
1952, Raytheon released 10 000 CK718s to its commercial customers, the
hearing-aid manufacturers.

Kids' stuff

Still, the manufacturing process wasn't perfect, and Krim was stuck
with a mound of noisy, low-gain CK718s that weren't good enough for
hearing aids. Faced with the prospect of destroying thousands of
rejects, Krim, who a decade later as CEO of RadioShack would sell the
electronic hobby retailer to leather craft store chain Tandy Corp.
(Dallas), wondered: could what was scrap to a company be gold to a
hobbyist? As a youth in the late 1920s, he had built a mechanical TV
set. It included a radio receiver and a Bakelite disk drilled with 16
strategically placed holes to scan a Raytheon Kino neon lamp that
projected the picture. Resourceful even then, he used his mother's
milkshake mixer to rotate the disk and obtain an image.

"I thought, jeez, wouldn't these rejects make a hell of a good thing?
So when the guys wanted to break them up, I said, you can't do that—
they're worth something," recalls Krim. "I loved to build experimental
stuff and I just wanted the kids to have these. And nobody had ever
seen a transistor."

Not even editors of the major electronics publications at the time. So
in February 1953, Krim invited the editors of all the major
electronics magazines, including Electronics and the now defunct Radio
and TV News, to his office for a demonstration of CK718 rejects that
were relabeled CK722. "Their tongues were hanging out," recollects
Krim.

From the pens of those amazed editors the word spread about what the
ordinary hobbyist could do with a transistor. And kids across the
United States started putting together radios and oscillators and
speakerphones, a few of which are now enshrined in the Transistor
Museum.

Infatuation contagion

After visiting the Raytheon archives, Norm and I drove over to Jack's
house to see the Transistor Museum collection [ see photos]. It was
the first visit for both of us, and I was curious to see how Norm
would react to seeing bits of the history he helped create.

Our first stop was the kitchen table, where Jack presented each of us
with a single-transistor CK722 radio kit he had made especially for
this occasion. It featured a gleaming silver CK722, a Raytheon CK705
germanium diode, an ancient pair of magnetic headphones, a vintage
comb-tuning capacitor, a variable inductor loopstick to fine-tune
reception of a station, and, appropriately, two RadioShack AAA
batteries.

The delight on Norm's face erased 80 years, and for a few minutes he
was that same precocious boy who'd built his own crude TV. Norm hung
on Jack's every word as he showed us how he'd converted a double CD
case into the kit's rudimentary circuit board. I marveled at Jack's
ingenuity, but was frankly more interested in the components, the
smooth twisting action of the comb tuning capacitor, the bright red of
the CK705 diode, and, of course, the beguiling silver CK722, my first
transistor.

Then we followed Jack down to the basement to see where the virtual
Transistor Museum makes its real home.

We passed his son's matte-black Alien computer setup and an Altair
computer resplendent in all of its toggle-switched glory before
entering the inner sanctum. Here in this meticulously arranged room,
Jack had everything he needed to make the museum run, including his
server, scanner, digital camera, and broadband connection. The room
was lined with shelf after shelf of plastic containers, each packed
with hundreds of diodes, ICs, transistors, and other devices that Jack
had bought on eBay. Norm, it's safe to say, was dumbstruck. The father
of the CK722 was standing in the delivery room of the Semiconductor
Era.

For an hour, Jack dazzled us with objects and stories that put
everything we saw in historical context, right down to the dozens of
packages for different transistors and vacuum tubes he brought out. He
discussed the nuances of different transistors, identified according
to year and lot number, and how, precisely, they were stamped. He
displayed handmade gadgets people had sent him for his collection,
including a one-transistor radio on a wooden board made by Terry
Hosking, which, with its beautifully hand-wound antenna coil, looks
like something you might see in a SoHo art gallery [see photo].

Jack placed tiny chips of germanium in our hands, revealing the
mystery at the heart of the junction transistor. And he told Norm what
a marketing genius he was for maintaining the CK722's brand identity
for so long. As Raytheon got better at making transistors, they got
smaller. While Norm could have housed the devices in a smaller
package, that would have changed the look and the form factor of a
familiar friend to hobbyists. So Norm potted the smaller transistors
in the same size package and extended the CK722's brand life.

And while it might sound as if the hobbyist version of the Stockholm
syndrome had set in, as I stood there listening to the stories flowing
back and forth between Jack and Norm, one archivist to another, the
warm fuzzies came on, my own love for the CK722 blossoming right there
in Jack Ward's basement.

To Probe Further
To visit Jack Ward's Transistor Museum on the Web, see the site at
http://www.transistormuseum.com.

The original CK722 site is at

http://www.ck722.com.

For Bob's Virtual Transistor Museum and History Web Site, go to
http://users.arczip.com/rmcgarra1.

From: Robert Baer on 12 Feb 2010 05:22

---

John Larkin wrote:
> A 955 acorn tube:
>
> ftp://jjlarkin.lmi.net/Acorn.JPG
>
> John
>
>
I give up; where is the oak?

From: Robert Baer on 12 Feb 2010 05:41

---

Greegor wrote:
> On Feb 11, 10:43 pm, John Larkin
> <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote:
>> A 955 acorn tube:
>>
>> ftp://jjlarkin.lmi.net/Acorn.JPG
>>
>> John
>
> http://en.wikipedia.org/wiki/955_acorn_triode
>
> It doesn't say when these were first made or when they stopped making
> them.
>
> They use a reference book from 1954 though.
>
> I got some surplus computer boards once in the 1970's
> that had some tiny tubes that might have been peanut tubes.
> They layed parallel to the G10 epoxy PC board with
> a small metal holding clip riveted to the G10.
>
> A lady friend made jewelry using some that were
> new and so the glass had no blackening and the
> shiney guts were visible.
>
> The first transister oscillator project I built about 1970
> (I was 10 or 11) used two old blue CK722's.
>
> I had the specs but had no idea they were
> vintage 1955-1957, about 14 years old or
> that they were such a historical part.
>
> http://transistorhistory.50webs.com/ck722.jpg
>
> http://spectrum.ieee.org/biomedical/devices/the-irresistible-transistor
>
> The Irresistible Transistor
> Fifty years ago this month, a man embraced his inner hobbyist and gave
> thousands of engineers their first transistor
>
> Image: Jack Ward
>
> With this ad, Raytheon Co. introduced the CK722 and slightly better
> CK721 (less noise, higher gain) in 1953.
>
> BY Harry Goldstein // March 2003
>
> Is it possible to love a transistor? Certainly what Jack Ward feels
> for the Raytheon CK722, the first transistor sold to the general
> public, goes beyond casual affection. He's collected thousands of
> early transistor specimens, including dozens of CK722s. His stately
> yellow Victorian home on a quiet, tree-lined street in Brookline,
> Mass., has a basement crammed with enough code oscillators, Geiger
> counters, radios, hand-wrought circuit boards, transistorized hearing
> aids, subminiature vacuum tubes, diodes, resistors, and capacitors to
> make any collector of vintage electronic gear drool. He's written one
> book about the CK722 and has started another about early transistor
> history at RCA. When he's not working as associate director of quality
> for the Bedford, Mass., facility of gene-chip maker Affymetrix Inc.,
> he's busy maintaining his virtualTransistor Museum on the Web and is
> widely acknowledged by fellow collectors as a techno-anthropologist
> par excellence .
>
> "My wife's very supportive, and my younger two children think it's
> fairly amusing, and probably not a bad way to have a mid-life crisis,"
> says Ward of his family's reaction to his passionate pursuit of
> transistor history. Far from thinking that his dad's a square, Ward's
> oldest son, Nick, who is pursuing a B.A. in physics, is learning a lot
> from his old man. "Nick can't believe how fast technology changes and
> that the people I talk to have changed the world," adds Ward, who as
> curator of the online museum has shifted his focus from collecting
> early transistors to collecting oral histories from the engineers who
> sparked the Semiconductor Era.
>
> For Ward and the CK722, it was love at first sight. The year was 1959:
> Fidel Castro had just taken Cuba, John F. Kennedy was campaigning for
> U.S. president, Buddy Holly was flying around on what would be his
> last tour, and Texas Instruments and Fairchild Semiconductor had both
> filed patent applications for something called an integrated circuit.
> Recalling himself as a boy of 10 marching into his local radio
> distributor and plunking down his allowance for his first transistor,
> Ward [ see photo] taps into the same wonder that gripped him when he
> laid eyes on the CK722, which Raytheon Co. (Lexington, Mass.) made
> available to hobbyists through RadioShack stores starting in March
> 1953.
>
> "They were probably only a couple bucks at the time, but just the
> excitement of actually owning one of these was intense. The package is
> quite spectacular, you know, the actual shape of the device and the
> color," he says. "The blue ones, for instance, the iridescent blue
> color is just gorgeous."
>
> With his new transistor, Ward built a radio, just a simple tuned
> circuit with a germanium diode to detect a signal and a CK722 as an
> audio amplifier. "I turned it on in my room at night after lights out,
> and listened to rock and roll or a baseball game," he says wistfully.
> "For sheer excitement, I can't think of a parallel with another thing
> in technology. I'm tempted to say the PC, but that doesn't quite
> capture it. You see, it's different than that."
>
> Love potion No. 722
>
> Ward wasn't the only boy smitten. Tens of thousands of CK722s were
> sold between 1953 and the mid-1960s. The irresistible transistor cast
> a spell over even die-hard vacuum tube enthusiasts like Terry Hosking.
> By the ripe old age of 12, Hosking, now a senior application and
> design engineer with SB Electronics Inc. (Barre, Vt.), had concluded
> that vacuum tubes were the only way to go.
>
> "I told some of my relatives that I didn't think that transistors were
> going to amount to much," Hosking told me. "A few weeks later, I got a
> care package from them with a blue CK722 and a Sylvania 2N35
> transistor and a couple books that showed how to hook them up. I was
> amazed to find that the transistor radio I built would pick up the
> local stations without an external antenna and ground like I had to
> use with the tube radio."
>
> Transistors weren't just sensitive devices, they were the mysterious
> oracles of a new age�"Just a little solid block of black plastic with
> three thin wires sticking out," says Tom Lee, associate professor of
> electrical engineering at Stanford University. Lee started fooling
> around with transistors when he was only five. At that time, in the
> mid-1960s, RadioShack sold "blister packs" of five transistors for a
> dollar. "They were the only transistors a kid could easily obtain with
> saved-up pocket change," he says. "The CK722 is the first recollection
> I have of that transistor type, indeed, of any transistor type at all.
> The things seemed magical."
>
> And messy in a way tinkerers love. Junior engineers constructing
> projects out of transistors and circuit boards had to hone basic shop
> skills: measuring, cutting, drilling, and assembly. "Of course, the
> most important skill to master was soldering," says Bob McGarrah, now
> staff system planning engineer at Central Illinois Light Co. (Peoria,
> Ill.).
>
> What madeleines were to Proust, solder is to McGarrah. "The unique
> smell of the hot flux still brings back happy memories," he says, one
> of which is a of small audio amplifier that he discovered had an
> impedance high enough not to draw a dial tone when connected to a
> telephone line. A huge fan of the TV spy drama "The Man from
> U.N.C.L.E.," young McGarrah used the amplifier to practice his
> surveillance skills by listening in on family members' phone calls.
>
> Connecting on the Internet
>
> Like old high school chums who reunite on Classmates.com and realize
> that they shared a crush on the same girl way back when, Hosking, Lee,
> Ward, McGarrah, and dozens of others linked up on the online auction
> site eBay in the late 1990s and began swapping stories along with
> vintage transistors.
>
> "Old transistor collectors tend to be a small, close-knit bunch," says
> McGarrah, who runs his own transistor history Web site. "The power of
> the Internet to bring together such a narrowly focused group of
> hobbyists is amazing."
>
> Ward concurs: "Without the Internet, none of this interaction would
> really be possible." Inspired by the online communities he saw
> sprouting up around vacuum tubes, Ward decided to use the Internet to
> research the history of early transistor radios. He soon became more
> interested in radio components than the radios themselves, "in how
> these little devices were developed, and what a profound impact they
> had on society."
>
> In 1999, Ward scratched an itch to write and took as his subject his
> first transistor. He began working on The Story of the CK722, and put
> up the http://www.ck722.com Web site. Here he posted the fruits of his
> research�pictures of the CK722 and other early Raytheon transistors,
> charting the 722 through its three case colors, silver, black, and
> that iridescent blue [see " Transistor Family Tree,"]. He also posted
> pictures of old ads, circuit schematics, packages, and devices people
> made with the CK722 that they sent him for his growing collection.
>
> Deep into his yearlong project, Ward attended the Cambridge-based
> Massachusetts Institute of Technology's (MIT's) monthly hamfest, a
> flea market for the "geek to the max," as he puts it. He made known to
> fellow collectors his eagerness to find out more about the origins of
> his favorite transistor. "Someone mentioned that they thought Raytheon
> had a historian," Ward remembers. "So I called up Raytheon, and sure
> enough, there was one. A gentleman named Norman Krim."
>
> Krim's tale
>
> It turns out that 89-year-old Norm Krim is not only Raytheon's
> archivist, he's a living link to the roots of the electronics
> industry. He's also the father of the CK722 [see photo].
>
>
> Photo: LARRY VOLK
>
>
> Norman Krim, father of the CK722 that Jack Ward bought as a child, is
> now curator of the Raytheon archives. Here he sits at his kitchen
> table and plays with a CK722 radio made and presented to him by Ward.
> Late one chilly night this past October, as he and I sat in the
> kitchen of his Newton, Mass., home sipping green tea and munching on
> roasted almonds, Krim spun his story. Having been a student of
> Raytheon founder Vannevar Bush at MIT, Krim took a job with his
> mentor's company as an engineer in the receiving tube division in
> 1935. By 1938, Krim had developed subminiature tubes for hearing aids.
>
> The expertise gained in that work earned six patents on the
> subminiature tubes found in the proximity fuses used in U.S. Army
> artillery and antiaircraft shells, credited by some historians with
> turning around the Battle of the Bulge in late 1944. After the war,
> under Krim's steady hand, Raytheon's receiving tube division dominated
> the market for hearing-aid tubes with a 90 percent share through the
> 1940s.
>
> As the industrial war machine was winding down, the semiconductor
> revolution was just revving up. At Raytheon's archives in Lexington,
> the morning after our late night bull session, Krim showed me a
> letter. Dated 9 July 1948, it was addressed to Laurence K. Marshall,
> then president of Raytheon, inviting him to Bell Telephone
> Laboratories Inc. (Murray Hill, N.J.) to see a demonstration of "a new
> device called a Transistor," specifically the point-contact transistor
> invented by Walter Brattain, John Bardeen, and William Shockley.
> Marshall was busy that day and tapped Krim to go in his place. What he
> saw shook him to his very core.
>
> "I was worried that my success had been with tubes, and this was
> threatening my job," Krim recalls. "So what the hell was I going to
> do? I was going to get into transistors."
>
> Krim's crash program eventually led to the introduction of the world's
> first commercially available transistor, the CK703 in 1948, less than
> six months after the Murray Hill demonstration.
>
> But the CK703 had some problems. The germanium point-contact transistor
> �actually two pointed wires, 125 �m in diameter and 25-50 �m apart, in
> contact with the signal-amplifying semiconductor�had to be handmade
> with watchmaker precision, which precluded cost-effective mass
> production. And they were none too robust. The slightest shock could
> ruin them, which made them useless for hearing aids and just about
> everything else.
>
> So Krim shifted gears and leveraged his division's growing expertise
> in semiconductor technology to make germanium diodes, which had a
> ready market as signal detectors in TV sets. By 1950, Raytheon was
> cranking out 20 000 diodes a day and Krim was promoted to vice
> president of the receiving tube division, where the diodes were being
> made.
>
> Double jeopardy
>
> Meanwhile, as germanium diodes and subminiature tubes poured out of
> Raytheon's plants, William Shockley was about to jolt the world again,
> this time with the junction transistor. Krim was fortunate enough to
> room with Shockley for over a week in the spring of 1951, while both
> were serving on a military procurement advisory board known as the
> Baker Committee.
>
> "Shockley would be proofreading a paper after dinner every night. He
> told me, 'I'm going to publish an article in the Physical Review, and
> you should remember, pick up that article.' When I got a copy of his
> article on junction transistors, that was it for me. The light bulb
> went on." And Krim's engineers swung into action.
>
> Their junction transistors were simple devices made of two indium dots
> (emitter and collector) alloyed to either side of a germanium chip.
> But the germanium wasn't pure enough and the initial devices failed.
> Later in 1951, at a symposium conducted by Bell Labs, Krim's team
> learned the value of zone refining: passing an RF coil over a quartz
> tube containing a large block of germanium crystal and melting
> portions of it in sequence. That got the impurities to migrate to the
> end of the ingot, which could then be lopped off, leaving a pure
> crystal behind.
>
> Knowing that quartz tubes were key to making germanium pure enough for
> junction transistors, the crafty Krim cornered the market on quartz
> tubing. "And I did one other thing," he says with a sly smile. "There
> was a company in Missouri called Eagle-Picher, at the time the
> country's biggest zinc refiner. They threw out germanium as a
> byproduct of zinc refining. So I bought it all up."
>
> But as Raytheon prepared to introduce its germanium junction
> transistor, dubbed the CK718, yields stayed stubbornly low. Water
> vapor and other environmental contamination occurring during the
> manufacturing process were to blame. To get around the problem, Krim's
> team used infant incubators as "clean boxes," so technicians wearing
> rubber gloves could reach in and assemble transistors while minimizing
> exposure to ambient conditions. Yields went up, and by the end of
> 1952, Raytheon released 10 000 CK718s to its commercial customers, the
> hearing-aid manufacturers.
>
> Kids' stuff
>
> Still, the manufacturing process wasn't perfect, and Krim was stuck
> with a mound of noisy, low-gain CK718s that weren't good enough for
> hearing aids. Faced with the prospect of destroying thousands of
> rejects, Krim, who a decade later as CEO of RadioShack would sell the
> electronic hobby retailer to leather craft store chain Tandy Corp.
> (Dallas), wondered: could what was scrap to a company be gold to a
> hobbyist? As a youth in the late 1920s, he had built a mechanical TV
> set. It included a radio receiver and a Bakelite disk drilled with 16
> strategically placed holes to scan a Raytheon Kino neon lamp that
> projected the picture. Resourceful even then, he used his mother's
> milkshake mixer to rotate the disk and obtain an image.
>
> "I thought, jeez, wouldn't these rejects make a hell of a good thing?
> So when the guys wanted to break them up, I said, you can't do that�
> they're worth something," recalls Krim. "I loved to build experimental
> stuff and I just wanted the kids to have these. And nobody had ever
> seen a transistor."
>
> Not even editors of the major electronics publications at the time. So
> in February 1953, Krim invited the editors of all the major
> electronics magazines, including Electronics and the now defunct Radio
> and TV News, to his office for a demonstration of CK718 rejects that
> were relabeled CK722. "Their tongues were hanging out," recollects
> Krim.
>
> From the pens of those amazed editors the word spread about what the
> ordinary hobbyist could do with a transistor. And kids across the
> United States started putting together radios and oscillators and
> speakerphones, a few of which are now enshrined in the Transistor
> Museum.
>
> Infatuation contagion
>
> After visiting the Raytheon archives, Norm and I drove over to Jack's
> house to see the Transistor Museum collection [ see photos]. It was
> the first visit for both of us, and I was curious to see how Norm
> would react to seeing bits of the history he helped create.
>
> Our first stop was the kitchen table, where Jack presented each of us
> with a single-transistor CK722 radio kit he had made especially for
> this occasion. It featured a gleaming silver CK722, a Raytheon CK705
> germanium diode, an ancient pair of magnetic headphones, a vintage
> comb-tuning capacitor, a variable inductor loopstick to fine-tune
> reception of a station, and, appropriately, two RadioShack AAA
> batteries.
>
> The delight on Norm's face erased 80 years, and for a few minutes he
> was that same precocious boy who'd built his own crude TV. Norm hung
> on Jack's every word as he showed us how he'd converted a double CD
> case into the kit's rudimentary circuit board. I marveled at Jack's
> ingenuity, but was frankly more interested in the components, the
> smooth twisting action of the comb tuning capacitor, the bright red of
> the CK705 diode, and, of course, the beguiling silver CK722, my first
> transistor.
>
> Then we followed Jack down to the basement to see where the virtual
> Transistor Museum makes its real home.
>
> We passed his son's matte-black Alien computer setup and an Altair
> computer resplendent in all of its toggle-switched glory before
> entering the inner sanctum. Here in this meticulously arranged room,
> Jack had everything he needed to make the museum run, including his
> server, scanner, digital camera, and broadband connection. The room
> was lined with shelf after shelf of plastic containers, each packed
> with hundreds of diodes, ICs, transistors, and other devices that Jack
> had bought on eBay. Norm, it's safe to say, was dumbstruck. The father
> of the CK722 was standing in the delivery room of the Semiconductor
> Era.
>
> For an hour, Jack dazzled us with objects and stories that put
> everything we saw in historical context, right down to the dozens of
> packages for different transistors and vacuum tubes he brought out. He
> discussed the nuances of different transistors, identified according
> to year and lot number, and how, precisely, they were stamped. He
> displayed handmade gadgets people had sent him for his collection,
> including a one-transistor radio on a wooden board made by Terry
> Hosking, which, with its beautifully hand-wound antenna coil, looks
> like something you might see in a SoHo art gallery [see photo].
>
> Jack placed tiny chips of germanium in our hands, revealing the
> mystery at the heart of the junction transistor. And he told Norm what
> a marketing genius he was for maintaining the CK722's brand identity
> for so long. As Raytheon got better at making transistors, they got
> smaller. While Norm could have housed the devices in a smaller
> package, that would have changed the look and the form factor of a
> familiar friend to hobbyists. So Norm potted the smaller transistors
> in the same size package and extended the CK722's brand life.
>
> And while it might sound as if the hobbyist version of the Stockholm
> syndrome had set in, as I stood there listening to the stories flowing
> back and forth between Jack and Norm, one archivist to another, the
> warm fuzzies came on, my own love for the CK722 blossoming right there
> in Jack Ward's basement.
>
> To Probe Further
> To visit Jack Ward's Transistor Museum on the Web, see the site at
> http://www.transistormuseum.com.
>
> The original CK722 site is at
>
> http://www.ck722.com.
>
> For Bob's Virtual Transistor Museum and History Web Site, go to
> http://users.arczip.com/rmcgarra1.
"A couple of bucks"???
Bullsh*t!
The first time i saw the CK722 on the market, the price was $12 - way
too much for mere curiosity to justify.
I waited past at least two price drops and bought my first one at
$199 and a few weeks later kicked myself as the price dropped to the
$0.99 level, where it stayed.

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