Red and Fuzzball on Convergence
January 1958 Radio-Electronics Article
not sure when storytelling as a style of technical writing went the
way of vacuum tubes (probably about the same time, come to think of
it), but this article from the January 1958 edition of Radio-Electronics
is a prime example of how such prose was utilized. Two characters, Red
and Fuzzball, meet at a coffee counter and discuss the intricacies of
color convergence in color television sets. Such issues are not a concern
with today's electron-beam-less displays, but back in the day, it made
the difference between an acceptable picture and frustrating images
with color fringing. Maybe you remember those days. After having read
many articles on troubleshooting, repairing, and aligning TV sets prior
to LCD and LED displays, I have a real appreciation for the knowledge
of really good repairmen. In some ways the vacuum tube sets were easier
to troubleshoot because the tech could easily pull tubes from sockets
to make voltage and resistance readings rather than needing to unsolder
transistors or ICs.
January 1958 Radio-Electronics
of Contents]These articles are scanned and OCRed from old editions of the Radio & Television News magazine.
Here is a list of the Radio-Electronics articles I have already
posted. All copyrights (if any) are hereby acknowledged.
See all available
vintage Radio-Electronics articles.
Red and Fuzzball on Convergence
By Robert G. Middleton
Fuzz is still learning about color TV - the hard way
Fig.1 - (left) Blue lateral corrector separates blue and green
lines for easier checking.
Fig.2 - (center) Make the red
and blue lines parallel.
Fig.3 - (right) Red, green and
blue vertical center lines must all be parallel.
still got a job?" asked Fuzzball anxiously, as he sat down beside Red
at the counter. "Take it easy," Red replied. "Old Fatpants is late himself
this morning - he don't even know that you didn't show."
hand shook visibly as he reached for the cup of coffee. "So where you
been, anyhow?" Be asked curiously.
"It worked out to be sort
of a lost weekend for me," Fuzzball explained. "I took one too many
"There are times," Red chuckled, "when Fuzz lives in
a world of his own."
"There ain't no such world," Bess snorted,
and flounced off.
"There was a good reason for me falling off
the wagon though," Fuzz said in self-defense.
"Always is," Red
agreed. "What's yours?"
"It's that installation out on the South
Side," said Fuzz. "Line voltage drifts up and down so much that I can't
converge the picture tube for sour apples."
"That's easy," replied
Red. "All you got to do is put in an automatic line-voltage regulating
"That's easy?" Fuzzball asked. "This guy won't
even buy an outdoor antenna. I can't get him off my back."
have mercy," Red breathed. "The penny-pinching public again."
"What can I do?" Fuzzball asked helplessly.
"Suppose he calls up Old Fatpants and complains?"
"Let him. I'll talk to Fatpants. I been on these hey-rube runs
"Can you cash me
"The answer is no. Here's a fin I'll give you. That
way nobody ain't kidding nobody."
"Thanks, Red. I dunno what
I'd do without a buddy like you."
"I know what you'd do - and
so do you."
Not to change the subject but
I got a new way to converge a picture tube that I like better."
"When I start making the vertical dynamic,
I kill the red gun and line up the green dots with the blue dots."
"Nothing wrong with doing it that way, if you want to."
"The way you started me out," explained Fuzzball, "I left the red
gun on. It's less complicated to adjust the green by itself."
"At the beginning, yes," Red agreed. "But it's a sure bet that after
you get some more experience, you'll be leaving the red gun on."
"I suppose you're right," Fuzzball remarked. "Right now, it seems
easier to work with two colors at a time."
"After you get experience,"
Red explained, "you'll learn to pay no attention to the colors you're
not working with. It will just be a bother to you, then, to be turning
guns off and on."
"I see what you mean," Fuzz replied. "Tell
me this," said Red, "do you keep the green and blue dots converged in
"I took your hint before, Red. I use crosshatch
to start the job and I found it's easier that way."
"But I don't keep the green and blue lines converged
at the center unless I'm working in a real dark room."
"Hope so," Fuzz replied. "I found that when
there's light shining on the screen, it's easier to judge if the green
and blue lines are straight with each other if I keep them separated
a little bit." (See Fig. 1.)
"Most techs would agree with you
on that one," Red assured him.
"One thing the set manufacturers
have done that really helps on this convergence, though."
"They are either mounting the dynamic controls on the front
of the set or on a box that you can bring around to the front."
"You can say that again. It's cut convergence time just about in
"OK. I will say it again," Fuzzball grinned.
"You're a real character," Red replied disgustedly. "But what are you
doing after you line up the green and blue vertically?"
then I kill the green gun and turn the red gun back on."
"I adjust the red beam magnet or the blue lateral corrector
to separate the red and blue lines a little bit."
"Just like the green. I adjust the red vertical amplitude and
tilt controls to make the red and blue lines straight with each other
up and down the screen." (See Fig. 2.)
"I hope you mean you
are watching just the vertical center column on these vertical adjustments,"
"What do you think I am. Stupid?" Fuzzball
"I'd rather not answer that question yet," Red observed.
"Then what next?"
"That's when I turn the green gun back on
and check to see whether the green light is still straight." (See Fig.
"A little green touchup might be in order," Red agreed.
"Finally, I adjust the beam magnets and
the lateral corrector to bring the three color lines together and make
a white line."
"How's your luck running?" "Sometimes there's
a little tattle-tale color showing at the top or bottom," Fuzzball admitted.
"You'll never get it 100% perfect," Red reassured him. "We discussed
"But you can't see it very far back from the set,"
"Better hadn't, at viewing distance anyhow."
"It's a funny thing," Fuzzball mused, "when there's a little color
showing at the top of the white line, the dynamic adjustments will shift
the color fringing to the bottom of the line, or to the middle. But
you got to leave a little fringing somewhere."
hep," Red remarked, "and just where do you leave the fringing?"
"Does it make a difference?" Fuzz asked innocently.
does. You'll have lots less complaints if you leave the final fringing
at the bottom."
"But why should that be?" asked Fuzz.
"Simply because programming usually carries the action above center
screen - that's where John Q. Public looks the
got to admit it makes sense," Fuzzball agreed.
"Now what next?"
"That's when I switch over to white dots and work on the blue
amplitude and tilt controls."
"You can keep on with the crosshatch
if you want to," Red advised.
"How would you do that?"
"Well, the crossovers on the hatch give you the same use as dots."
"I guess they would, at that."
"So you can look up and
down the vertical center line, and see how the crossovers are doing."
"It always looks OK at the center of the screen," Fuzzball reminded
"That's right. The static adjustments make it easy to bring
the center in."
"But the crossovers are pretty cruddy at the
top and bottom of the screen."
Now the blue
So you should open up the blue vertical amplitude control wide and adjust
the blue vertical tilt to get the same blue separation at both the top
and bottom of the screen."
"You get away from the dot routine
on this deal," Fuzz remarked.
"Naturally, because you're working
with a different type of pattern."
"Well, after I get equal
blue line spacing at the top and bottom, where do I go from there?"
"Next thing you do is turn down the blue amplitude to get equal
blue line spacing all the way up and down the vertical center column."
"But I might have to touch up the blue tilt adjustment," Fuzzball
"Only a miracle could save you," Red agreed. "There's
quite a bit of interaction."
"And, then, when the blue lines
are spaced exactly the same amount from the yellow lines all the way
up and down the center column, the static adjustments would give final
"Fuzzball, there are times when you are
so bright you dazzle me," Red said effusively. "Permit me to buy you
another cup of coffee."
"That's coffee?" Fuzzball exclaimed,
ducking agilely as Bess heaved a creamer at him.
"We can use
crosshatch all the way on the horizontal dynamic convergence too, if
we want to," Red added.
"How about giving me a rundown?" Fuzzball
"Well, you started off by telling me how you kill
the red gun when you start the vertical. So you can start the horizontal
the same way, killing the red gun."
"Makes it easier to remember
that way," Fuzz observed.
"Then," continued Red, "turn the green
horizontal amplitude and the green horizontal phase at the same time
and get the green crossovers on the same side of the blue crossovers.
Get the crossovers the same, all the way along the horizontal center
"Guess I might need to hit the beam magnets or lateral
corrector a little to separate the green and blue," Fuzzball suggested.
"But definitely," Red agreed, "and positively if there is much
light in the room."
"So after I get the green crossing all on
the same side of the blue crossings, where do I go from there?" Fuzz
"Then you get down to fine points," Red explained. "Look
at the spacings between the green and blue crossings. You'll find it's
dollars to doughnuts that the spacings aren't all exactly equal amounts."
"So I suppose I got to touch up the green amplitude and phase
to make all the crossover spacings the same."
you do exactly the same thing for the red crossovers. Kill the green
gun and turn on the red gun. Adjust the red amplitude and phase to get
equal crossover spacings, with all the red crossings on the same side
of the blue crossings."
"That makes a pretty good routine for
remembering," Fuzzball remarked. "What do I do next?"
the green gun back on. Both the red and green crossovers will be pretty
near even from the blue crossovers. A little touchup on the red and
green controls should do it about right."
"What about the blue
horizontal dynamics?" Fuzz asked.
"I'm getting to that," Red
"But, first, you want to make sure you are satisfied
with the job so far. Get on the static adjustments and make the pattern
white in the center of the screen. Then, you might want to do just a
little more touching up to get real good crossovers at the same points
all along the horizontal center line."
"Then I go to the blue
horizontal controls?" asked Fuzz.
"Absotively. Now we straighten
up the blue line and bring it in with the yellow line."
far, I've always been resonating the blue phasing coil," Fuzz ventured.
"Saves time," Red agreed. "You should do it on this all-crosshatch
routine also. Open up the blue horizontal amplitude and adjust the blue
horizontal phasing coil for a peak, smack in the center of the screen."
"That's just like we were using dots." "Right. Then, back off
on the amplitude until the blue line is as near parallel with the yellow
"But I'll probably need to touch up the blue phasing
"You're reading my mind," Red stated. "The touchup will
give the parallel spacing you're looking for between the blue and yellow
"And the static controls will give me final overall
convergence," Fuzz suggested.
"Just about," Red agreed. "But
there are a couple of little points to keep in mind."
"Look carefully at the vertical convergence. You might
have knocked it out a trifle, and need to touch it up a wee bit."
"Anything else?" asked Fuzz.
"Yep. Check the corners
of the screen. There's no adjustment here, but sometimes if you see
a little fringing in the corners, you can compromise a little to improve
it, without hurting other parts of the screen noticeably."
exclaimed Fuzzball, blowing hard. "And I took up television for a living.
I could of had a job in a putty-knife factory and nothing to worry about."
"Maybe you could get a job as a pilot on a rocket to the moon,"
Fuzzball rose to his feet. "Give the gal her
money, Red, and let's get out of this booby trap."
another creamer on the door behind the fast-moving Fuzzball's back.
Posted February 4, 2014