kx250rider
03-28-2006, 11:57 AM
I have this article from Modern Electronic Service Dealer magazine; April 1963... By Irv Tjomsland. I had known about "The Iron Monster of Burbank" through a SCARS member who had been part of the experiment, Bruce McCalley. This was a very neat account of how an early color TV prototype experiment would have been!
Be it known that I am reproducing this article FOR EDUCATIONAL PURPOSES ONLY, and hope I don't get yelled at for a copyright issue :tears:
http://home.earthlink.net/~crosleycars/IronMonstor.jpg
The Story of California's
IRON
MONSTER
By
IRV. TJOMSLAND
The tempo of Color talk picked up in mid 1953. Follow the short-lived CBS Color Wheel approval in 1950 of the industry had worked together to produce a system and gradually the impression developed that the FCC would approve the new standards about Dec. 17th.
At that time I was working for the Burbank division of Dean Electronics of Long Beach, under Andy Futchik, branch manager.
In our efforts to provide something more than an extra discount on tubes we had conducted a series of information meetings on such subjects as Scope Interpretation. Alignment, and Sweep Systems, and it was natural that we would think of devoting a meeting to information on the new color system. I am sure if either Andy or I had known what would follow the decision to hold that meeting we would have had reason to hesitate!
As soon as I started to plan material for the meeting I realized that I knew almost nothing about the new color system. Much of the material which had appeared had been of a publicity nature and certainly not very helpful in a technical presentation.
In this position I turned to the man who had always been the solution to such a problem, Pete Pedersen. A few days after I mentioned the project he showed up with a nice fat book entitled "A Review of NTSC Committee Findings." and he started to outline the points of the new system.
In two or three nights of reading he had digested the material in the book and presented a working outline of the transmission and receiver operation of the new system.
It was immediately apparent that we had not only all the material needed for one meeting, but also enough for many more monthly meetings.
In addition, since the book contained a complete schematic of the industry receiver we realized that we might build a color demonstrator to follow up the theoretical material.
Andy and I discussed the problems of developing a demonstrator. We naturally felt that the color tube and sweep system would be the main hurdles.
Walt Lessing and Ed Mann of RCA were contacted and it was determined that a Color CRT and Sweep Component Kit were in the L.A. warehouse. For obvious reasons these
could not be sold until the FCC formally approved color, but we were assured that we could depend on delivery if the FCC took favorable action. Wth this promise we decided to launch the project.
PRELIMINARY PLAN
Pete and I were quite sure that we could rework a black and white receiver for the RF, IF, and Sync functions. With the Sweep Kit we planned to build from scratch, and improvise on the balance.
About this time Larry Vickers of Bell Radio offered to furnish a black and white chassis, and somehow he and his bench man Armond Rea located the RCA T-100 Pete and I had felt would be most suitable for this portion.
Pete undertook a custom alignment project, and by apply every bit of his experience he was able to adjust coupl. capacitance, and resonance to a point where the overall response curve closely approached the ideal as outlined in the manual. This was to remain stable for several years, and never caused a moment's trouble.
The Vertical sweep was rebuilt to the new standards and the horizontal and video systems removed. A cathode follower was installed to couple the video to the color processing system.
About this time I received a call from Glenn Gossard, in charge of Quality Control at Standard Coil. He said, "When you build that color set you are going to need a set of inductances. We `just happen' to have a complete set of experimental units that you can have." I hadn't realized it, but when he brought in the kit there were more than fifty different items, including peaking coils, convergence controls, band-pass couplers, traps, and many other assoiated items. I am sure this kit reduced our working time by 50%, and I hadn't been aware of the problem until Glenn called!
Bill Barron and Chet Jur were associated those days, and they turned up with "samples" of delay lines and solved another problem.
John Colbert of Triad came drifting in one morning and said that. if we were strong enough to carry it in, he had a power transformer for the job. The 200 volt secondary winding had a resistance of less than 1/2 ohm and appeared able to furnish 2000 milliamperes of plate current without ever heating. In addition by mounting it in the center of the assembly it determined the center of weight and practically insured the job against being tipped over.
THE CONSTRUCTION' PERIOD
On the morning of Dec. 17th Ed and Walt delivered the color CRT and the sweep kit.. and immediately the Tjomsand garage became a prototype construction site.
By Christmas the outline of the Iron Monster had taken shape. As the photo on our front cover indicates the black and white T-Ip0 chassis is mounted vertically at the left. The horizontal sweep system, rectifier and regulator is at the right, and the color processing circuits are in the front center panel. The bottom panel contained the bandpass. phase lock, crystal oscillator, and killer circuits.
Left center is the video or luminence pave). center is the "L"' and right the "Q" panel. At the top is a horizontal panel containing the matrix and adder circuits. plus the operating and temperature controls.
By taking advantage of the holidays I vas able to devote several hundred hours to the construction and "firing of the project. Pete spent every minute he could spare from his job preparing for the time we would "'fire up."
One problem was obvious: we were sure +m would need test equipment. first to make the Monster operational and second for use in lecture demonstration work.
Some years previously I had built a "count-down" sync train similar to the circuit employed by RCA in their closed circuit TV equipment. Pete dusted off this equipment and proceeded to design a color bar generator circuit around it.
As he worked on the test equipment project and I struggled with the Monster we encountered many problems that required extra information. Pete seemed to ham e unlimited lines of communication within the network. station. and RCA organizations. Many times we were to comment on the assistance that was extended by people we hardy_- knee. and the cooperative spirit of people in the industry.
Of course; during all this I had to take off time for my job. and I expect my weeks were split with about 45 hours going to my sales work and 50 hours to the Monster.
FIRING UP
Rv January 20th we were too ways ready for the big moment. Pete had a working model of lest gear. and the Iron Monster was due to be "fired up."
We had the greatest respect for the safety of our Color CRT so all our preliminary tests were made using a 17HP-I connected in turn to each gun circuit. II have often wondered how the 17HP4 withstood the more than 30.000 volts we fed it from the horizontal sweep system.)
Pete picked up the information that CBS would be on the air at d A.M. with a color test, and came over to work on evaluation. The temperature in the garage stood at -I0 degrees, and we had a futile 3-hour wait. Later in the day we found out that network difficulties had prevented the test. and itt had been rescheduled for the next morning. We were tired. and a little short of enthusiasm. but still managed to make it up in time.
When the test started we were able to make the phase detector lock in and the demodulators deliver color. It wasn't correct as far as color was concerned- but who cared: it worked. It was at this point that I realized that I did not have full information of polarity relations in the coils I was using and that I faced at least six possibilities of polarity reversal.
Pete drew numerous charts to indicate the relative luminance values of the color signals. and with this at hand I ran dozens of tests which involved alignment for amplitude balance. phase- delay. and band-pass characteristics.
Gradual)- the system smoothed out and I was pretty sure I had "plus" I and Q identified, that I had enough gain for the burst keyer and phase lock to operate, and a fe+~ days later NBC presented a half hour of live color.
Sure enough. when the program came on we had color. It was a bit on the "pretty" blue side. hut the girls in the musical comedy had nice flesh tones- the roses in the vase were red_ and we thought we had it made.
FIRST PUBLIC SHOWING
Friends in the field were starting to ask when they could see "Color," so when NBC announced that they would , arr+ their "Fights" in color we knew the time had come. A fter all the set had received several programs without much trouble and we were a little over confident.
We moved the Monster from the garage to the Dean warehouse where we could accommodate a crowd. About a hundred people were on hand for the show.
The show came on. the fighters fought, but no color. Pete called the network and was assured that the program was in color.
When I studied the picture closely I could see that fine horizontal bars were dimly visible and reasoned that the crystal oscillator was far off frequency. The oscillator frequency control changed the many bars to three or four and we plugged in a new 6AN8 color locked in and for the remaining minute of the show the hundred spectators saw yellow blood on rose colored fighters!
It was at least a year before I realized that the antenna we had on top of the Dean building was slightly less than good for color work. The response of that particular antenna at the suhcarrier frequency was so bad that we had less than l0 Jr of normal signal for operation.
Color programs were desperately scarce, but we had an audience whenever a show was announced. and we estimated that more than three thousand people saw their first color show on the Monster.
SERVICE DElIONSTRATION
Color test equipment became availabe from several sources. so we planned a series of service familarization meetings. Our attendance problems became acute: we had room for a hundred at the most and often had two hundred show up for a meeting, Before color was made official we had found it necessary to repeat each month's lecture material four times to accom crowd.. and due to limitations of color programs we found it impractical to follow this procedure.
One discovery we made early: there was little or no useful purpose served by trying to teach convergence via the lecture and demonstration method. To make sense the serviceman had to develop the feel for control, no[ just believe it could be done. After two or three demonstrations to large audiences we changed the format and invited service people. in groups of three to five, in for an evening of setup drill. and felt we enjoyed much better results.
CONVERSION TO 21"
Our original 15GP22A had cost $26.00, and late in 195 the 21AXP22 was announced at $125.00. The natural result was that we converted to the new tube, and adapted the convergence circuitry of the CT-55. To our delight x+°e found that the original -I0 degree Ryback would readily sweep the 70 degree tube when we re-arranged the tap system. What we didn't notice was that the high voltage tended to go to 37.000 volts. and if the regulator was not carefully adjusted a glow tended to surround the tube when the room was darkened.
The first 21" tube was troubled by gun shorts. so Andy stocked a replacement color tube. probably the first distributor in the territory to do so. and in the course of backing up the demonstrator sold several.
Norb Dean had scheduled a meeting in Long Beach on the fifth floor of a public building and about two hours before the meeting was to start. the CRT shorted, the high voltage system cracked like a gun shot- and the blue gun went out with an open heater winding.
Fortunately it was about five minutes before closing time at Burbank, and Bruce McCallev made the run down with the new tube. It took a change -in the brightness circuit to make it operate, but ten minute, before show time it was on the air.
SALE TO THE SRTT
Late in 1956 the Monster was sold to the Society of Radio and Television Technicians of Van Nuys. For about a year -Stan Auerbach of Chroma TV carried on the training work in connection with the other SRTT and RTA organizations.
Following this Morris Bloombaum moved the demonsttor to Pierce College for use in connection with his classes. Last seen, the -Monster reposed in the Reseda shop of Hugh McClellan and Dudley Andrews.
During its many travels it could always be counted on to produce a 270 line picture (maximum resolution where color take out traps are employed), and when an alignment project was properly completed on the color circuits could produce an excellent color picture.
The "P"channel gain was always a little low so it took careful adjustment to avoid excess green in flesh tones. but this condition is common in many later receivers.
Because of the inside out circuit arrangement nearly all test points and adjustments were readily accessible for training and instruction.
As Pete and l worked on the project in late `S3 and early 'Sf- we felt quite sure that color would catch on. but I doubt if either of us thought that the first big year would not come for nine more years.
It always seemed to its that color sales and service were just a little hit ahead in the San Fernando Valley. and I think we liked to believe that the Iron Monster might have been connected in a small way with that activity.
(END)
Charles
Be it known that I am reproducing this article FOR EDUCATIONAL PURPOSES ONLY, and hope I don't get yelled at for a copyright issue :tears:
http://home.earthlink.net/~crosleycars/IronMonstor.jpg
The Story of California's
IRON
MONSTER
By
IRV. TJOMSLAND
The tempo of Color talk picked up in mid 1953. Follow the short-lived CBS Color Wheel approval in 1950 of the industry had worked together to produce a system and gradually the impression developed that the FCC would approve the new standards about Dec. 17th.
At that time I was working for the Burbank division of Dean Electronics of Long Beach, under Andy Futchik, branch manager.
In our efforts to provide something more than an extra discount on tubes we had conducted a series of information meetings on such subjects as Scope Interpretation. Alignment, and Sweep Systems, and it was natural that we would think of devoting a meeting to information on the new color system. I am sure if either Andy or I had known what would follow the decision to hold that meeting we would have had reason to hesitate!
As soon as I started to plan material for the meeting I realized that I knew almost nothing about the new color system. Much of the material which had appeared had been of a publicity nature and certainly not very helpful in a technical presentation.
In this position I turned to the man who had always been the solution to such a problem, Pete Pedersen. A few days after I mentioned the project he showed up with a nice fat book entitled "A Review of NTSC Committee Findings." and he started to outline the points of the new system.
In two or three nights of reading he had digested the material in the book and presented a working outline of the transmission and receiver operation of the new system.
It was immediately apparent that we had not only all the material needed for one meeting, but also enough for many more monthly meetings.
In addition, since the book contained a complete schematic of the industry receiver we realized that we might build a color demonstrator to follow up the theoretical material.
Andy and I discussed the problems of developing a demonstrator. We naturally felt that the color tube and sweep system would be the main hurdles.
Walt Lessing and Ed Mann of RCA were contacted and it was determined that a Color CRT and Sweep Component Kit were in the L.A. warehouse. For obvious reasons these
could not be sold until the FCC formally approved color, but we were assured that we could depend on delivery if the FCC took favorable action. Wth this promise we decided to launch the project.
PRELIMINARY PLAN
Pete and I were quite sure that we could rework a black and white receiver for the RF, IF, and Sync functions. With the Sweep Kit we planned to build from scratch, and improvise on the balance.
About this time Larry Vickers of Bell Radio offered to furnish a black and white chassis, and somehow he and his bench man Armond Rea located the RCA T-100 Pete and I had felt would be most suitable for this portion.
Pete undertook a custom alignment project, and by apply every bit of his experience he was able to adjust coupl. capacitance, and resonance to a point where the overall response curve closely approached the ideal as outlined in the manual. This was to remain stable for several years, and never caused a moment's trouble.
The Vertical sweep was rebuilt to the new standards and the horizontal and video systems removed. A cathode follower was installed to couple the video to the color processing system.
About this time I received a call from Glenn Gossard, in charge of Quality Control at Standard Coil. He said, "When you build that color set you are going to need a set of inductances. We `just happen' to have a complete set of experimental units that you can have." I hadn't realized it, but when he brought in the kit there were more than fifty different items, including peaking coils, convergence controls, band-pass couplers, traps, and many other assoiated items. I am sure this kit reduced our working time by 50%, and I hadn't been aware of the problem until Glenn called!
Bill Barron and Chet Jur were associated those days, and they turned up with "samples" of delay lines and solved another problem.
John Colbert of Triad came drifting in one morning and said that. if we were strong enough to carry it in, he had a power transformer for the job. The 200 volt secondary winding had a resistance of less than 1/2 ohm and appeared able to furnish 2000 milliamperes of plate current without ever heating. In addition by mounting it in the center of the assembly it determined the center of weight and practically insured the job against being tipped over.
THE CONSTRUCTION' PERIOD
On the morning of Dec. 17th Ed and Walt delivered the color CRT and the sweep kit.. and immediately the Tjomsand garage became a prototype construction site.
By Christmas the outline of the Iron Monster had taken shape. As the photo on our front cover indicates the black and white T-Ip0 chassis is mounted vertically at the left. The horizontal sweep system, rectifier and regulator is at the right, and the color processing circuits are in the front center panel. The bottom panel contained the bandpass. phase lock, crystal oscillator, and killer circuits.
Left center is the video or luminence pave). center is the "L"' and right the "Q" panel. At the top is a horizontal panel containing the matrix and adder circuits. plus the operating and temperature controls.
By taking advantage of the holidays I vas able to devote several hundred hours to the construction and "firing of the project. Pete spent every minute he could spare from his job preparing for the time we would "'fire up."
One problem was obvious: we were sure +m would need test equipment. first to make the Monster operational and second for use in lecture demonstration work.
Some years previously I had built a "count-down" sync train similar to the circuit employed by RCA in their closed circuit TV equipment. Pete dusted off this equipment and proceeded to design a color bar generator circuit around it.
As he worked on the test equipment project and I struggled with the Monster we encountered many problems that required extra information. Pete seemed to ham e unlimited lines of communication within the network. station. and RCA organizations. Many times we were to comment on the assistance that was extended by people we hardy_- knee. and the cooperative spirit of people in the industry.
Of course; during all this I had to take off time for my job. and I expect my weeks were split with about 45 hours going to my sales work and 50 hours to the Monster.
FIRING UP
Rv January 20th we were too ways ready for the big moment. Pete had a working model of lest gear. and the Iron Monster was due to be "fired up."
We had the greatest respect for the safety of our Color CRT so all our preliminary tests were made using a 17HP-I connected in turn to each gun circuit. II have often wondered how the 17HP4 withstood the more than 30.000 volts we fed it from the horizontal sweep system.)
Pete picked up the information that CBS would be on the air at d A.M. with a color test, and came over to work on evaluation. The temperature in the garage stood at -I0 degrees, and we had a futile 3-hour wait. Later in the day we found out that network difficulties had prevented the test. and itt had been rescheduled for the next morning. We were tired. and a little short of enthusiasm. but still managed to make it up in time.
When the test started we were able to make the phase detector lock in and the demodulators deliver color. It wasn't correct as far as color was concerned- but who cared: it worked. It was at this point that I realized that I did not have full information of polarity relations in the coils I was using and that I faced at least six possibilities of polarity reversal.
Pete drew numerous charts to indicate the relative luminance values of the color signals. and with this at hand I ran dozens of tests which involved alignment for amplitude balance. phase- delay. and band-pass characteristics.
Gradual)- the system smoothed out and I was pretty sure I had "plus" I and Q identified, that I had enough gain for the burst keyer and phase lock to operate, and a fe+~ days later NBC presented a half hour of live color.
Sure enough. when the program came on we had color. It was a bit on the "pretty" blue side. hut the girls in the musical comedy had nice flesh tones- the roses in the vase were red_ and we thought we had it made.
FIRST PUBLIC SHOWING
Friends in the field were starting to ask when they could see "Color," so when NBC announced that they would , arr+ their "Fights" in color we knew the time had come. A fter all the set had received several programs without much trouble and we were a little over confident.
We moved the Monster from the garage to the Dean warehouse where we could accommodate a crowd. About a hundred people were on hand for the show.
The show came on. the fighters fought, but no color. Pete called the network and was assured that the program was in color.
When I studied the picture closely I could see that fine horizontal bars were dimly visible and reasoned that the crystal oscillator was far off frequency. The oscillator frequency control changed the many bars to three or four and we plugged in a new 6AN8 color locked in and for the remaining minute of the show the hundred spectators saw yellow blood on rose colored fighters!
It was at least a year before I realized that the antenna we had on top of the Dean building was slightly less than good for color work. The response of that particular antenna at the suhcarrier frequency was so bad that we had less than l0 Jr of normal signal for operation.
Color programs were desperately scarce, but we had an audience whenever a show was announced. and we estimated that more than three thousand people saw their first color show on the Monster.
SERVICE DElIONSTRATION
Color test equipment became availabe from several sources. so we planned a series of service familarization meetings. Our attendance problems became acute: we had room for a hundred at the most and often had two hundred show up for a meeting, Before color was made official we had found it necessary to repeat each month's lecture material four times to accom crowd.. and due to limitations of color programs we found it impractical to follow this procedure.
One discovery we made early: there was little or no useful purpose served by trying to teach convergence via the lecture and demonstration method. To make sense the serviceman had to develop the feel for control, no[ just believe it could be done. After two or three demonstrations to large audiences we changed the format and invited service people. in groups of three to five, in for an evening of setup drill. and felt we enjoyed much better results.
CONVERSION TO 21"
Our original 15GP22A had cost $26.00, and late in 195 the 21AXP22 was announced at $125.00. The natural result was that we converted to the new tube, and adapted the convergence circuitry of the CT-55. To our delight x+°e found that the original -I0 degree Ryback would readily sweep the 70 degree tube when we re-arranged the tap system. What we didn't notice was that the high voltage tended to go to 37.000 volts. and if the regulator was not carefully adjusted a glow tended to surround the tube when the room was darkened.
The first 21" tube was troubled by gun shorts. so Andy stocked a replacement color tube. probably the first distributor in the territory to do so. and in the course of backing up the demonstrator sold several.
Norb Dean had scheduled a meeting in Long Beach on the fifth floor of a public building and about two hours before the meeting was to start. the CRT shorted, the high voltage system cracked like a gun shot- and the blue gun went out with an open heater winding.
Fortunately it was about five minutes before closing time at Burbank, and Bruce McCallev made the run down with the new tube. It took a change -in the brightness circuit to make it operate, but ten minute, before show time it was on the air.
SALE TO THE SRTT
Late in 1956 the Monster was sold to the Society of Radio and Television Technicians of Van Nuys. For about a year -Stan Auerbach of Chroma TV carried on the training work in connection with the other SRTT and RTA organizations.
Following this Morris Bloombaum moved the demonsttor to Pierce College for use in connection with his classes. Last seen, the -Monster reposed in the Reseda shop of Hugh McClellan and Dudley Andrews.
During its many travels it could always be counted on to produce a 270 line picture (maximum resolution where color take out traps are employed), and when an alignment project was properly completed on the color circuits could produce an excellent color picture.
The "P"channel gain was always a little low so it took careful adjustment to avoid excess green in flesh tones. but this condition is common in many later receivers.
Because of the inside out circuit arrangement nearly all test points and adjustments were readily accessible for training and instruction.
As Pete and l worked on the project in late `S3 and early 'Sf- we felt quite sure that color would catch on. but I doubt if either of us thought that the first big year would not come for nine more years.
It always seemed to its that color sales and service were just a little hit ahead in the San Fernando Valley. and I think we liked to believe that the Iron Monster might have been connected in a small way with that activity.
(END)
Charles