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-   -   Gilfillan Prototype Set (http://www.videokarma.org/showthread.php?t=264845)

miniman82 07-29-2015 09:49 PM

Gilfillan Prototype Set
 
Sorry this took so long, been busy as heck at work getting ready for various inspections.

Here's the 21" color prototype I won at this years convention auction, in all its 300lb wood cased glory, enjoy.

http://miniman82.4t.com/images/Gilfillan/IMG_4496a.JPG

Unfortunately the CRT is dead, pay no attention to the tag.

http://miniman82.4t.com/images/Gilfillan/IMG_4493a.JPG
http://miniman82.4t.com/images/Gilfillan/IMG_4495a.JPG
http://miniman82.4t.com/images/Gilfillan/IMG_4497a.JPG
http://miniman82.4t.com/images/Gilfillan/IMG_4503a.JPG

tvcollector 07-29-2015 10:04 PM

I love the style of the set.. Probably one of the most earliest sets I really like.. Just not too crazy about doors being on a TV set... What year you think it's from?

jbivy 07-29-2015 11:04 PM

Shes lovely, great score :)

ChrisW6ATV 07-30-2015 02:00 AM

Very nice-looking set, Nick. Is that a hinged panel giving access to the underside of the chassis on the side? I have seen a similar feature on a Hoffman Colorcaster 4021A from 1955. That appears to be an original design as opposed to a CTC-4 or 21-CT-55 duplicate.

dieseljeep 07-30-2015 10:42 AM

Quote:

Originally Posted by ChrisW6ATV (Post 3139590)
Very nice-looking set, Nick. Is that a hinged panel giving access to the underside of the chassis on the side? I have seen a similar feature on a Hoffman Colorcaster 4021A from 1955. That appears to be an original design as opposed to a CTC-4 or 21-CT-55 duplicate.

Gilfillan was always a higher end product. I didn't remember them making television sets, let alone color sets.
I was surprised to see they used that el-cheapo Sarkes-Tarzian tuner.
The same PITA tuner that Warwick used in the Silvertones in the mid-50's. :sigh:

Jeffhs 07-30-2015 11:56 AM

I am surprised as well to find out Gilfillan made TVs. I see Gilfillan radios every now and then on eBay or CL, but this is the first of their televisions (color, yet!) I have ever seen. Since this set is a prototype, however, I'm not surprised. It may have been manufactured in very limited numbers, so this one is probably one of a very few such sets in existence in the United States. It may have been made very shortly after RCA's NTSC color television system was commissioned here, so I would not expect to have found very many of these TVs anywhere.

How could this Gilfillan TV be an original design, when RCA had a corner on color TV production in this country? :scratch2: It would have had to use inventions of RCA, as no one else was making color TVs at the time (early 1950s). The chassis would almost have to be an early RCA one, such as CTC2 or CTC4.

The CRT should be easy to find, if the original is dead (no emission? Open filaments?). I cannot imagine the 21AXP22 being so rare, even today, however, as to be unobtainable. Worse comes to worst, you could always get one from a junker set, not necessarily RCA; I'm sure other TV manufacturers used round CRTs in their early sets as well until the mid-1960s, when rectangular tubes became popular.

BTW: I had no idea, until I read dieseljeep's post, that Sarkes-Tarzian television tuners were cheap ones. I was under the impression for years that S-T was one of the better makes of tuners. What made them "cheap"? Flimsy designs with cheap plastic parts, underrated components that failed after only a very short time, or . . . ? I can see such tuners being used in cheap 1970s-'90s pre-DTV portables, but good grief, not in high-end sets. After all, I am sure Zenith and other well-known TV manufacturers would not have been caught dead using cheap tuners (or other cheap parts) in their TVs in the '50s.

dtvmcdonald 07-30-2015 01:17 PM

When color TV was new, RCA made available the special needed parts. These
really included only deflection yokes, convergence coils, and horizontal output transformers, though others
could get the color transformers as well. Everything else could be standard parts, at least for sets using 21AXP22s and later CRTs.
RCA actually encouraged others to make their own designs. They didn't care ... they'd
get the royalties anyway. At least, if any of the sets actually sold.

Electronic M 07-30-2015 02:58 PM

Nice score, Nick!

RCA did not hold patent on all possible circuits that could demodulate color. GE had an earlier 15GP22 based set that used their own original chroma demod circuit that did not use an oscillator (and GE kept using that thru the end of the tube era). Look at some of the 60's designs like Zenith's beam gate demodulator or Motorola's (or was it Admiral?) single tube self-oscillating demodulator....The former I would not be surprised if Zenith had designed back in their 1954 prototypes. Magnetic convergence was also a Zenith design (RCA's 15GP22 was electrostatic convergence, and they would have kept making them had others not passed them by). The QAM color signaling method it's self was Philco's idea. The reason most makers went with RCA clones is that it was usually easier/cheaper than to make it your self....At least until profitable volume was selling.

miniman82 07-30-2015 03:52 PM

Quote:

Originally Posted by ChrisW6ATV (Post 3139590)
Very nice-looking set, Nick. Is that a hinged panel giving access to the underside of the chassis on the side? I have seen a similar feature on a Hoffman Colorcaster 4021A from 1955. That appears to be an original design as opposed to a CTC-4 or 21-CT-55 duplicate.

Yes, there's a catch on the inside of the cabinet and you lift it up to open the door. Pretty damn convenient, if you ask me.

It's somewhat of an original design, I'll explain with a bit of a history lesson.


After the CT-100 came out, an almost instantaneous size war erupted between the manufactures of color sets. The only exception was the brief segue into higher technology in the 15" realm with the 15HP22, which printed its phosphor dots directly onto the curved faceplate vice having a flat dot plate as the 15GP22 did. This innovation was quickly put to use by CBS to create the 19VP22 19" CRT, and we were off to the races. This would have been circa mid 1954 or so.

Later that year 19" sets started showing up in the market place (it was CBS and later Motorola and Hoffman making the sets), and it became evident to RCA that something had to be done since 15" sets were now obsolete and no one was buying them. So they embarked on a development program leading to the issuance of a document called LB-962, which was their report on a developmental 21" set in September of 1954. A link to my scanned copy which was included in the Gilfillan documentation is below (warning it's more than 20mb in size):

http://miniman82.4t.com/images/Gilfillan/LB-962.pdf

From the documentation, it's apparent to me that there are stark similarities to the CTC-4 chassis. So why did the CTC-2B show up instead of the one shown in LB-962? I can only assume that RCA knew they had to come up with something fast, because they were being beaten at their own game by other manufactures. Being that the chassis shown in LB-962 was in its developmental stages at that time, I suspect what happened was this (from an earlier email to Steve McVoy):


27 July, 2015:

"My assumption right now is that the reason the 21-CT-55 came before this one was that RCA had piles of Merrill chassis laying around from the CT-100 run, so instead of retooling the entire production line to suit the prototype outlined here they opted to modify the CTC-2 to support a 21" CRT. We have to remember that the 'size war' was in full swing at that period in color TV, and there had to be considerable pressure on RCA to get something to market which could compete with the 19" sets that had come out earlier that year from CBS and others. So I'm assuming they took left over Merrill chassis, slapped in the horizontal section from this prototype (the flyback looks identical to the one in the 21-CT-55), and sent it out the door."



It's the only explanation I can think of that makes sense. Interestingly this LB-962 document still calls the CRT by its developmental designation C-73685, and since the 21-CT-55 came out a few months later and used a 21AXP22, that places the emergence of the 21AXP22 CRT somewhere between Late September and early December of 1954. The date code on the CRT in the Gilfillan is 52nd week of 1954 and it's a 21AXP22 not a developmental tube, so it's in the right ballpark.



Anyhow, back to the topic at hand.

Gilfillan must have applied to get on board with the RCA developmental 21" program at some point, because their circuit is very similar to the one outlined in LB-962. Not identical, but very close. RCA was known to work with other people in developmental programs (see the history of the NTSC color signal, the panels were made up of manufactures across the entire TV spectrum, pun completely intended), so it makes sense. They got a copy of LB-962, changed a few things so as not to get caught up in patent infringement disputes as is still the custom in industry today, and made the set you see here.

Documentation states only 6 were ever built, I'm unaware of any others turning up.

MRX37 07-30-2015 04:03 PM

Quote:

Originally Posted by miniman82 (Post 3139641)

Documentation states only 6 were ever built, I'm unaware of any others turning up.

Holy crap talk about rare!

miniman82 07-30-2015 04:08 PM

Quote:

Originally Posted by Jeffhs (Post 3139621)
The CRT should be easy to find, if the original is dead (no emission? Open filaments?).

It's got next to no emission, even at 8 volts. I just got 3 electron gun assemblies in the mail though and I'm heading to the ETF next week tube in hand... :thmbsp:



Quote:

I had no idea, until I read dieseljeep's post, that Sarkes-Tarzian television tuners were cheap ones. I was under the impression for years that S-T was one of the better makes of tuners. What made them "cheap"? Flimsy designs with cheap plastic parts, underrated components that failed after only a very short time, or . . . ? I can see such tuners being used in cheap 1970s-'90s pre-DTV portables, but good grief, not in high-end sets. After all, I am sure Zenith and other well-known TV manufacturers would not have been caught dead using cheap tuners (or other cheap parts) in their TVs in the '50s.
Can't comment on the quality of the tuner, I'm not a tuner buff. It seems to click solidly when I turn it though, so they at least made the detents decent. lol I suppose we'll find out just how good it is soon enough, I'll probably have to do a full alignment on it when I get the chassis recapped. This one has UHF built in, nice feature for a prototype set to have in 1954.

miniman82 07-30-2015 04:43 PM

First things first, I have to deal with this:

http://miniman82.4t.com/images/Gilfillan/IMG_0101a.JPG

Findm-Keepm 07-30-2015 05:51 PM

Quote:

Originally Posted by miniman82 (Post 3139641)
Documentation states only 6 were ever built, I'm unaware of any others turning up.

Quote:

Originally Posted by MRX37 (Post 3139644)
Holy crap talk about rare.

Yes, rare indeed.

There were 6 space shuttles built, and I've seen three, so rare indeed. :D

Sandy G 07-30-2015 07:06 PM

Looks to me you've got a JIM-DANDY new Playpretty... W/your technical smarts, I expect to see it makin' "Glorious Lollipop Color" very soon... (grin)

dieseljeep 07-30-2015 08:55 PM

[QUOTE=miniman82;3139645]It's got next to no emission, even at 8 volts. I just got 3 electron gun assemblies in the mail though and I'm heading to the ETF next week tube in hand... :thmbsp:
Regarding my opinion of the tuners: the S/T tuners always seemed to be used in the lower end TV's of most of the big manufacturers. The tuners of that era of the Gilfillin color set, the tube sockets would crumble and the tube couldn't be reinserted. The later S/T tuners had the coil sticks, where the plastic retainer would crumble and the sticks would fall loose and the customer would try to turn the selector and break up the individual strips. Most of the time, the tuner was damaged beyond repair. The problem was generally related to the excessive use of tuner spray. :sigh:


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