Hi All, Within the past few weeks our family has relocated to Canada. In the Toronto Craigslist I found what turned out to be an RCA CTC5 colour TV. I duly purchased it and carted it home. (I specifically use the Canadian spelling of "colour" here for it appears this set was made for the Canadian market.)

From the back cover, the receiver was manufactured in Camden. But note the 25Hz power. A separate enormous power transformer was mounted on a subsidiary chassis beneath the main chassis. There is no power transformer on the main chassis. Note that the subsidiary chassis has 80mfd Canadian manufactured capacitors.

RCA Victor had a Montreal plant which manufactured US designed receivers with minor variations. I have an RCA 8T243 receiver made in Montreal which has different IF transformers and a 25Hz power transformer.

Colour broadcasting in Canada began in September 1966. Hence any receivers sold in Toronto prior to 1966 received colour programming from the US networks affiliates in Buffalo New York. WBEN TV (now WIVB) purchased RCA TK41 cameras in 1954 and WGR TV later became the NBC affiliate carrying the NBC colour programming. So a colour set in Canada as early as a CTC5P would be quite rare.

The interior of the cabinet has a whitewash paint sloppily applied. It looks as if the white wash may have been done in the factory. I would suggest that the set came to Canada by way of the Montreal RCA Victor company, where it was modified and interior whitewashed. I shall research this.

Anyhow, the set has been stored well. The cabinet is in good shape and the marks are mainly acculmulated dirt. The set seems to have had an easy life: all the receiving tubes are factory RCA and the 21AXP22 tests strong without any rejuvination or even waking up.

This will be a fun project once we have settled!

Really nice find there. Is the electrical service still operating at 25Hz in Canada?

Wow what a great find. It is a perfect new house warming present to yourself lol!
Beautiful Whitby, that was always one of my favorites without doors. The Wingate is my favorite with doors. I can't wait to see a picture on it, I bet it don't take much either.

Yes I was lucky to find this. It only goes to show that these sets are still lurking about and one never knows when they will pop up.

Toronto power was 25 Hz for many years. Being close to Niagara Falls, AC power reached Toronto in the 1890's. It was 25Hz from the 1890's until the 1950's. The swich to 60 Hz occurred i thought in about 1952-53 but I expect there were still 25 Hz spots in Southern Ontario Canada in the late '50's.

Incidently, the last 25Hz alternator at Niagara, the William Rankine plant closed just a few years ago.

Here is a link to the history of 25 Hz power:

http://www.ieee.org/organizations/pes/public/2008/jan/peshistory.html

You lucky Dawg !

That 25Hz 120VAC power transformer in theory would be happy at 240V at 60Hz. Except that all the secondaries would produce twice their rated voltages (like 12.6V instead of 6.3V). However, the high voltage secondary may get overvoltaged, if it's rated say 500V centertapped, it would produce 1000V centertapped, but the insulation might not take it. Of course the rest of the set won't like it either. :nono:

All of North America is now 60hz(with a few exceptions I'm sure). Probably best to look for a transformer that is rated at 117V 60Hz. Someone here with a junk chassis may have one. Probably wont be a direct fit size wise but can be made to work easily. Congrats on the 5. pretty rare there!

Green with envy here!

Really nice find there. Is the electrical service still operating at 25Hz in Canada?

The CTC5 25Hz power transformer will run perfectly well on 60 Hz. In fact it will probably run as cool as a cucumber. It doesn't need replacing as long as it checks OK.

I have an Admiral 7 inch 19A11 set that was built in Canada with a HUGE!!! 25 Hz power transformer and it runs very cool on 60 Hz here in PA.

Cliff

The CTC5 25Hz power transformer will run perfectly well on 60 Hz. In fact it will probably run as cool as a cucumber. It doesn't need replacing as long as it checks OK.

I have an Admiral 7 inch 19A11 set that was built in Canada with a HUGE!!! 25 Hz power transformer and it runs very cool on 60 Hz here in PA.

Cliff

That's what I was thinking. You can always go up in frequency, but you need the larger core size to pass 25Hz and stay cool. No need to change the primary voltage, that is always primary to secondary turns ratio dependent.

Seems to me I recall another Canadian modified CTC-5 posted here on VK, or AK at the time, some years ago. Not sure why they would whitewash the inside of the cabinet? Of course Canadians could also pick up the Detroit area early color broadcasts from Windsor, Ont. Would be interesting to see if U.S. color sets were advertised by RCA or dealers in these Canadian border cities in the 50's & early 60's.

-Steve D.

thats something i never hurd of, all of the utility service in canada was operating on 25 hz in the early yrs , learn something new everday. i want one of those cool sets someday.

That is a NICE find! Especially with the like-new CRT.

Is the "black box" in the location of a power transformer on the chassis empty?

Colour, indeed! I would hurry up and unpack so that I could start playing with that wonderful TV.

Phil Nelson

The CTC5 25Hz power transformer will run perfectly well on 60 Hz. In fact it will probably run as cool as a cucumber. It doesn't need replacing as long as it checks OK.
Correctomente bro. The set should be virtually 'plug and play' (after the usual pre-powerup procedures, cap replacements etc.). The big tranny will be very happy on 60 cycle. :guitar:

And its a DELUXE, with the 7-tube color stages. Nice treasure there!

Very curious! It appears that the original US Factory power transformer is on the main chassis. So just exactly how does this 25hz transformer chassis interface with the main chassis. Is the original 60hz transformer just sitting there disconnected? or is the 25hz chassis interconnected in some way as a step up to supply the primary of the 60hz trans on the chassis.

I don't understand why they would leave the original 60hz trans on the chassis.

cancel post. bad info.

Bravo!:banana: Another early RCA Colour set saved! And the fact its got a strong CRT is even better. If Miniman hasn't seen this thread yet, when he does I'm sure he will be grinning from ear to ear! What an awesome find! Congrats! :D

Wow. Excellent find. You wonder how many more are yet to be discovered. Maybe I'd better to move to Canada, it seems there has been a lot good stuff found up there this summer.

Very curious! It appears that the original US Factory power transformer is on the main chassis. So just exactly how does this 25hz transformer chassis interface with the main chassis. Is the original 60hz transformer just sitting there disconnected? or is the 25hz chassis interconnected in some way as a step up to supply the primary of the 60hz trans on the chassis.

I don't understand why they would leave the original 60hz trans on the chassis.

I'm going to guess that's just an empty can acting as a hole plug on the main chassis.

The spot where the US transformer sat does appear to be just an empty can. I haven't taken the set apart yet but the can is held in place by the unique Canadian Robertson head screws. The rest of the chassis has Philips, slot or hex head screws but the dummy can has the Robertson head screws.

I have a number of other early Canadian manufactured sets from the '30's onwards with massive 25Hz transformers. They now run a cool life on 60Hz with no problem. But I am curious for a set this late (1956-7) with a 25Hz power transformer implies that there were still pockets of 25Hz regions as late as then.

The set seems to have spent all of its life in an older section of Toronto which was perhaps late to switch to 60Hz. I suppose the only difference with this CTC5 is that an already heavy TV set is that much heavier (by about 10 to 15 pounds).

Nice.

It's a nice scroe, a la AK. lol

Glad that you got it. I really like the results on the CRT tester ;)

25hz right into the 50s ! what were they thinking ?
Could have been worse: Canada could have adopted PAL :eek:

25hz right into the 50s ! what were they thinking ?
ek:
Surprizingly, the town of Roosevelt, AZ was on 25 cycle from the adjacent Roosevelt Dam hydro plant until 1974.
Some kinda interesting notes on the Salt River Project's upgrade to their antiquated hydro system..
https://www.srpnet.com/gallery/trd/1971.aspx

25hz right into the 50s ! what were they thinking ?
Could have been worse: Canada could have adopted PAL :eek:

You have to consider that Toronto was one of the first electrified cities in the world. 25Hz was the first alternating current frequency. Once you establish a standard, it is always difficult to later change.

The availability of Niagara hydroelectric energy was very early (before 1900). Niagara power was transported via perhaps the world's first long distance high voltage corridor to Toronto. It was an enormous undertaking to make the switch to 60Hz in the '50's. I am surprised that 25Hz lasted into the color tv era!

In Toronto, the street railway system was fully electrified by 1893. I recall reading that the last horse drawn street railway car retired in that year. Eaton's Department Store building on Queen Street in Toronto, built in 1892-1893, was also fully wired for electrical lighting.

And also consider that the Rogers Radio company in Toronto was the first to sell fully 25Hz AC powered radio receivers in 1925: this was two years before RCA sold their first AC powered sets.

In hindsight 25Hz was a poor choice. But when you are an early adopter you must pay the price.

I got around to pulling the chassis on this set today. It is pretty well preserved with no tar on the HV components.

I looked at the power transformer(s) on the main chassis and second chassis. The main chassis mounted box is indeed a transformer and not an empty box. This being a 25Hz set, it appears as if the outboard transformer augments the main chassis transformer. I'll trace out the power supply circuit to see what modifications the Montreal factory did. Perhaps the Toronto Reference Library has the notes for the Canadian version of the CTC5-P?

The "Series 700 Notes" posted on the earlytelevision.org website suggests that to service the set, extension cables be employed between the removed chassis and the CRT. I am sure this has been discuused before in this forum: does anyone here know of the thread?

The cables look as if they should be easy to fabricate except for the convergence socket and plug. Does anyone have an extender to loan? Or alternatively, does anyone have the socket and plug to spare from a scrapped CTC5 chassis?

Cheers, Terry

Try to find an early Admiral scrapped chassis from a model 30A14CC1 or similar with the separate power supply chassis. The cable that connects the power supply chassis to the main chassis on that set uses the same plug and the socket. The one on the chassis can be removed to use as the female end. This is a very common B&W set and there are probably a number of parts chassis around. Else you will need to find a CTC5 parts chassis and a CTC5 convergence yoke to obtain both the socket and the plug to make up the needed cable.

Try to find an early Admiral scrapped chassis from a model 30A14CC1 or similar with the separate power supply chassis. The cable that connects the power supply chassis to the main chassis on that set uses the same plug and the socket. The one on the chassis can be removed to use as the female end. This is a very common B&W set and there are probably a number of parts chassis around. Else you will need to find a CTC5 parts chassis and a CTC5 convergence yoke to obtain both the socket and the plug to make up the needed cable.

Thanks Bob.

In the meantime until I find the appropriate connectore I shall extend the CRT and yoke leads and just leave the convergence coils attached to the chassis and off the CRT until I have confirmed a sensible picture.

I had a chance to work on the CTC5 today. I am methodically going through the chassis. I traced the 25Hz power supply and this is what I found.

The main chassis transformer was exchanged for a filament transformer only. The box on the chassis is indeed a transformer with 3 secondary windings: two for the 6.3v strings and 5v for the rectifiers. Note the Montreal factory substituted the unique Canadian Robertson head screws to hold the main chassis transformer.

The auxillary chassis has a whopping 20 pound transformer for the B supply only. The auxillary chassis also has a big filter choke and a pair of 80mfd 450v electrolytics which parallel with the 80mfd filters on the main chassis.

The 25Hz transformer will run cool at 60Hz and the extra filtering should make the B supply really clean.

There is evidence of the history of the set's manufacture. The date codes on the main chassis run from the 20th week of 1956 through to the 39th (the latest I could find on a component). The auxillary chassis electrolytics are dated December 1956 so the set's delivery was probably early 1957.

I was amused by the somewhat sloppy modification in one regard: some of the added connections were not soldered! The wire that attached to the rear socket for the primary of the B supply transformer was not soldered as was the B transformer lead that attached to the 5U4 rectifier plates. The connection to the 5U4 actually is burnt from arcing. I suspect the previous owner must have found the set unreliable hence it appears it was not used much. All of the receiving tubes, including the 6CB5 Horizontal Output and the 5U4 rectifiers appear original.

That chassis cleaned up nice. Looks like a nice project.

Some progress has been made with this set. I was lucky because this color TV receiver was not stressed or hammered during its life. Apart from a capacitor change on the vertical sweep board in 1965 (assumed from the 1964 capacitor date code and the 1965 repair tag on the HV cage) it looks as if it hasn't been touched. Oh yes, it had the contrast control mod. and from the look of it with same type paper capacitor, it was done at the same time.

I am currently reforming the electrolytics. It appears as if this set had not been powered for many years because the electrolytics were almost a dead short. By slowly reforming the dielectric, it is important to limit the current to about 5ma. Each capacitor took about 15 minutes to come up and at full rated voltage the current is about 0.1 mA. Because this is a Toronto set for 25Hz, two additional 80mfd capacitors were added to reduce the ripple. These are Canadian made Mallory electrolytics and they are taking much longer to reform. If the current does not drop below 1mA, I will be inclined to replace these.

Paper dielectric capacitor leak current and I will replace all paper capacitors which are in high impedance circuits and/or have above 20VDC across them. The larger 0.47ufd in the convergence circuit I will likely leave unless I have problems with convergence.

There was an interesting RCA modification made to the later CTC5N chassis: this involved changing the source of the plate voltage to the bandpass amp. and the plate supply to the color difference amplifiers. This was to prevent grey scale changes between color and B&W programs (color burst on vs off from the broadcaster). My set has the 10kohm dropper resistor which replaced a 6.8kohm unit. The 10kohm 10watt resistor dissipates about 8.5 watts! In the closed container chroma circuit, the heat melt the wax on the paper capacitors and burnt the insulation of wires running about half and inch away from the resistor. I plan to mount a 10k 20watt resistor outside the chroma can near the rectifiers.

I have attached the drawing of the chroma chassis highlighting the modifications RCA made on the later chassis. I have also attached the Radio College of Canada note of the Toronto 25Hz power conversion modification.

Lastly, I was curious to find that the static convergence is governed by the the DC obtained from the 6CB5 Horizontal Output cathode current. It would seem that investigating using a separate outboard DC supply would be more suitable. Would this element of the design possibly account for the frequent reports I have read about the drifting CTC5 convergence?

The Canadian Mallory electrolytics (80 ufd @ 450V) eventually reformed okay. Leakage current for each eventually dropped to 0.1mA at 450v after an hour for each. These capacitors were initially reluctant to come back: at first, when only 20VDC was applied, the leakage current was already 5mA and the current initially didn't appear to drop significantly. However, as these capacitors woke up the currently dropped right down.

I am now confident all the electrolytics have reformed okay and are fine. I am grateful the previous owner did not power up the set.

I today removed the components from the neck of the 21AXP22A for cleaning and examination. After reading the previous posts about disintegrating yoke covers, I was expecting the worst. Somehow the yoke on my set survived. I simply removed the yoke, cleaned off the dust and wiped it over with a damp cloth and found no problem with it. Curious why this one has survived and others I have seen are totally shot.

The cold in the Great White North preserved it, ehh ?!? (grin)

I suspect moisture has a lot to do with it. Better make a cast of that thing and get it reproduced before it falls apart!

Interesting, the one on my Wingate is ok too. It was produced in 1956, while my CTC4 was made in '55. The 4's cover has turned to dust. Both sets were from their original homes in a similar climate. I wonder if there was a change in material somewhere in production?

I have nearly replaced all the paper capacitors. I have gathered from an earlier thread that there are paper capacitors masquerading as mica look-alikes which should be changed.

I examined some of the paper capacitors for leakage and they are all bad! What is worse is when they are heated: I tried applying a little heat at the leakage increased at an alarming rate. Maybe I could use them as a temperature sensor in a thermometer.:thumbsdn: Boy, RCA must have really skimped on quality to keep the cost down!!!

I checked the electrolytics again and they have remained good apart from the additional Canadian Mallory 80mfd units for the 25Hz modification. These capacitors have become very leaky again and have lost the dielectric reforming I did a few weeks back. They will have to go... time to repack.

Going through the chassis (it is a CTC5 Deluxe) I have found an RCA factory modification which I feel was poorly executed. Mine is a "P" chassis and the later factory runs had the modification to improve grey scale between color (burst on) and black and white (burst off) programming. The plate supply for the first chroma bandpass amplifier was originally attached to the +300 vdc line through a 6.8kohm resistor dropping resistor. The modification moved the supply to the +385vdc line dropped through a 10kohm resistor. The modification meant that the power dissapation for the dropping resistor increased substantially (to 8.5 watts). This left charred insulation and components near the resistor. Because the chroma unit is enclosed, the ventilation is poor which made a bad situation worse. All the wax capacitors showed evidence of melting!

I decided to split the resistance: I installed a terminal strip near the rectifier ventilation and installed a 6.8k 10 watt resistor there. This was in series with a 3.3kohm 5 watt resistor mounted in the chroma chassis exactly where the 10kohm resistor was. The 3.3kohm resistor will dissipate now just over two watts.

Note the photo of the charred remains of the old terminal strip. I had already replaced the charred wiring. The original terminal strip was a miniature unit and I went to the trouble of modifying a larger terminal strip to fit. (I would not expect to make money on a CTC-5 anyhow:no:).

My set otherwise looks lightly used. I would be curious to hear from others who have the earlier versus the later deluxe chassis and this issue. There must be others with this problem...

which look alike paper mica are there, I did not change any thing but the tube paper caps on mine?

I had to replace a charred terminal strip/resistor, etc, in mine. I was thinking it was beneath the video board, under the removeable shield, but I might be wrong. I haven't noticed a problem with my yoke cover, either, but have plenty of other sets with that disease.

Yep. I think that is the same resistor and terminal strip. The video amplifier hasn't the shield underneath but the chroma demodulator chassis does.

This is plain bad design.:thumbsdn:

there are paper capacitors masquerading as mica look-alikes which should be changed.There were flat molded paper capacitors that resemble mica caps with colored dots. You can generally tell by the capacitance value whether it's paper or mica (micas usually have considerably smaller values). This article should help you tell them apart:

http://www.antiqueradio.org/recap.htm

My CTC-7 had a number of tubular paper caps, but none of the flat molded paper kind.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

I can't remember if mine had that burnt up resistor in it or not, but the chroma section was very waxy from all the caps melting.

I can't remember if mine had that burnt up resistor in it or not, but the chroma section was very waxy from all the caps melting.

I believe you'd be referring to your Wingate? It would depend whether it was the early or later chassis.

The melted capacitors certainly sounds like it.

I also checked the 2watt resistors nearby. The 22k (10%) measured 33k and the 82k (10%) measured 96k. They were right next to the resistor dissipating 8.5 watts. These are well out of tolerance and I am beginning to suspect a lot of the other resistors have drifted as well...

My CTC-7 had a number of tubular paper caps, but none of the flat molded paper kind.

Thanks for the information. There is a large slab on the horizontal osc. board that looks like it may be one. I'll check.

I recall trying to find a vertical sync. problem on my RCA 9TC275 for quite a while and I eventually traced it to a mica look-alike paper capacitor.

After recapping the chassis and after the preliminary checks, I applied power for my first time. The chassis is on the bench with deflection yoke, convergence coils and tuner attached but without the CRT.

The set powered up and appeared healthy. The first check is horizontal output performance: I checked the horizontal drive: RCA notes says 180p-p waveform and I measure 150v p-p. I adjusted the horizontal efficiency coild for minimum HO Tube cathode current. The HO Tube initially very slightly started to glow red on the plate after about 5 minutes and after adjusting the efficiency coil for minimum cathode current, the red glow disappeared.

Similar to the other CTC-5 thread, the HO Tube bias is a bit low and I attributed this on my set to the low drive at 150v p-p. I tried swapping the 6CG7 Horizontal Oscillator Tube with the 6CG7 Vertical Oscillator. The other tube reduced the drive to 130v p-p which seems to me that I have a couple of tired old tubes. (All the tubes are original to the set!)

This was one of the best preserved old sets I have ever had a chance to work on (in recent times). I plan to check the full alignment as I will be curious if, under this set's almost ideal 55 year life, how much it will have drifted.

I made/ obtained some extension cables to run the chassis with the CRT. I powered up the set with the CRT and the sweep circuits appear okay apart from minor vertical non-linearity. All the paper caps on the vertical sweep board have been replaced and since the height control is at it's limit, I suspect the 2.2Mohm oscillator plate resistor has drifted. I will investigate later.

The brightness control functions correctly at turn on but in about five minutes, the brightnes increases. I found the negative voltage for the brightness control drifting upward (towards positive). The negative voltage is obtained from the horizontal output tube grid leak bias and the 470kohm resistor coupling to the brightness control bad. So far so good.

I have been tracking down an intermittent corona from the HV cage. I used a long piece of plastic heat shrink tubing as a listening tube and tracked down the corona to the focus pot. I shall take this apart and investigate. I suspect the focus pot is troublesome in these sets.:scratch2:

I fed an RF modulated rainbow pattern to the antenna and see video of sorts on the CRT. Contrast is low and picture is washed out: I shall go through the video chain later.

Following the discussion on CTC5 low HV, I measured this set's HV at about 23kv. (I measured the HV with the Heathkit VTVM and HV probe I bought new in 1971!) I am pretty sure the calibration is still reasonable as I have recently compared other sets HV measurements. The measurement tolerance I would put at no more than +/-1000v.

In any case, the raster on this set is brighter than I would have expected for a 21AXP22A. It is bright enough to watch in a typical evening lamp lit living room although it may be tough to watch in a sunlit room if the curtains aren't drawn.

23KV is a little high, Should be 20KV per the RCA manual, That set will not be very bright compared to the newer sets.

I can't recall if you did the contrast mod (or undid it). it involves a mod to the cathode of the video out, in short it converts it to the same as a CTC-7 contrast control.

I can't recall if you did the contrast mod (or undid it). it involves a mod to the cathode of the video out, in short it converts it to the same as a CTC-7 contrast control.

The mod was done by someone earlier. I debated with myself whether I should put it back as original or leave the mod. I decided for now I would leave it and tidied up the modification work.

I did the same (cleaned up the work that had been done). I did notice the small cap (22pf IIRC) off the plate mounted on the bottom had NOT been removed and the other small cap a 330pf had not been changed to the 390pf (again IIRC). I don't know how much effect these changes would have had, but will do them next time I pull the chassis.

If you put it back to original, you wont like it. You will have HV loss and a blurred dim picture if the contrast is turned up all the way. I thought there was something seriously wrong with mine until I found an article on it. There is a thread or 2 on that subject here on VK

If you put it back to original, you wont like it. You will have HV loss and a blurred dim picture if the contrast is turned up all the way. I thought there was something seriously wrong with mine until I found an article on it. There is a thread or 2 on that subject here on VK

I tend to agree that it is better to keep the mod.. There must have been a reason that the subsequent chassis' had the new circuit. However, I also caught from the discussion that the larger overall cathode resistance with the bypass capacitor means that some of the DC coupling is lost. I will examine it more closely when I get the set working.

I removed and disassembled the focus pot for examination tonight. As I suspected, it had an open carbon track with a big burn hole. (See picture). The pot was replaced previously as there remained a trace of the old pot center lug attached to the soldered wire.

Success on the weekend! I have a reasonably good picture on my CTC-5 and it is running well. I have roughly set up purity and static convergence: I haven't touched the dynamic convergence just yet. Pictures to follow.

The third video IF was intermittent and I ended removing the tube socket because of the pin connections. I slightly bent the socket pins and re-installed the socket with virtually no damage to the copper trace: a good solder sucker is indespensible. The alignment of the third stage was affected. I plan to go through and test the complete RF/IF alignment shortly. In the meantime I simply touched up the last IF coil.

The 12BY7 developed control grid current after running a few minutes. That was the only bad tube in the set. (All the tubes looked original although the 12BY7 video amplifer had possibly been changed before: the rest of the RCA tubes read made in USA and the RCA 12BY7 read made in Canada.

I was beginning to investigate the alignment a couple of weeks ago when the RF Output lead of my HP8601A slipped off and hit the 5U4 rectifier socket while the set was on. Needless to say, it blew up the output hybrid amplifier of the generator. Fortunately, I recalled an article in which Matthew D'Asaro reverse engineered the HP hybrid and is offering them for sale. I purchased one and once it arrives I trust I will have my alignment equipment back in the running.

Lastly, after examining the video off the CRT with the contrast control modification, I am beginning to have second thoughts about keeping it. I notice with the contrast control advanced, the black level varies with picture CONTENT. At low contrast, it doesn't appear that bad. I believe it may be due to the bypass capacitance loses the DC level. I will look at this more and may consider modifying the contrast circuit back to original.

It is interesting that the interaction of brightness and contrast control adjustment is removed with the modification at the expense of superior DC coupling. I'd be curious to hear from others with similar thoughts or alternative arguements.

I worked on the CTC5 again tonight. For the last day since I got the set working, I have been scratching my head over a dynamic convergence problem. The convergence was really bad and the convergence control worked but would not bring the image into convergence.

I could not find anything electrically wrong. I ended up removing the convergence plug and found the convergence considerably better! In fact all the image seemed to require was static convergence. Puzzling over this the only thing I could remember is when disassembling the convergence assembly for cleaning, I may have reassembled it incorrectly. I then reversed the removable horseshoe windings and the dynamic convergence adjusted fine. In fact I am surprised how well it converged, especially after stories I have heard about the difficult adjustment procedure. The only problem I found was having to touch up static convergence frequently as I proceeded through the dynamic adjustments.

I am very grateful the 21AXP22A appears healthy and the greyscale adjustments were no problem. I have a temporary focus pot in place and a 2watt Allen-Bradley pot is on order. Other than replacing most of the paper capacitors and a few resistors and one tube, the set appears in good running order. I shall bench test it for a few weeks to keep an eye on the electrolytics to see if they continue to hold up. The last thing will be to go over the IF alignement when I get my sweep generator fixed.

I have taken some low res photos with my camera phone. I suppose some pictures are better than none. In one photo you will see how I was able to power it up attached to the CRT. I made extender cables for the HV, tuner to IF coax and the deflection yoke. I could not find a suitable donor Admiral set for the convergence socket and so positioned the chassis on a sturdy surface adjacent to the CRT so no extender was required. Similarly the CRT socket was easily attached from the same position.

Note the subchassis B+ transformer. The main chassis transformer is for filaments only. This was for the Toronto 25Hz market in 1956.

Note also the photo of the picture off the screen was via a mirror: my current repair shop is limited in space and the front is up against the wall, hence the mirror.

I did some more work on the set this past weekend. Thanks to Matthew D'Asaro, I managed to get my HP8601a sweep generator running again. I have had the HP8601a for years and it is a great machine. You may recall the RF Output lead slipped off and hit the 5U4 rectifier while on, when I was in the process of beginning IF alignment. This blew up the Hybrid output amplifier and thanks to Matthew's reverse engineering skill, he duplicated the HP Hybrid amplifier!

The audio IF alignment was slightly off and it has been fixed. The 4.5MHz trap (on the chrominance chassis) was way off: this would have accounted for the bad 920kHz beat. I initially just swept the video IF amplifier to study the response. The response was extended incorrectly to the sound region. I later found the overcoupled transformer between the first and second IF stages was misaligned. The traps and rest of the stages were touched up and it looks fine. I have not examined the tuner nor the chroma chassis alignment just yet.

I decided to "bake" the chassis in the cabinet. This gave me the opportunity to set up the purity and convergence properly for the first time. I had no problem with purity and given time, the convergence ended up pretty good. It was reassuring to find all the convergence controls worked. In the CTC5, I especially like the location of the controls on the front which made it very convenient to simply sit in front of the screen as you make the adjustments.

Despite the 21AXP22 testing excellent, the picture is still pretty dim by modern standards. But I can get an acceptible picture without blooming so long as the room lighting is subdued.

Bothered by the rather poor DC clamping in the video, I tried reverting the contrast control to original: I will open this in a separate thread.

I have been working intermittently on my Whitby set. I have checked the alignment of the Front End, realigned the Video IF and Sound IF apart from the earlier replacement of capacitors, resistors etc. I still haven't gotten around to the chroma bandpass, chroma demodulator and matrix alignment.

I last weekend fixed (at least tempoarily) the red static convergence pot, replaced a few tubes and increased the horizontal drive marginally. With the drive increase and the efficiency coil adjustment, I have the horizontal output current at about 200mA.

You may recall I opted to not change the electrolytics. They were all healthy and the two Canadian Mallorys used in the 25 Hz power modification are not too bad. The leakage on the Mallorys remains at about 200uA.

I have been running the set a few hours at a time the last few weeks and the only problem has been vacuum failures. When I received the set, all the receiving tubes, including the picture tube, was original. I have now had 4 tubes fail and be replaced (3rd VIF, Video Output, 3.58 MHz oscillator and the Z demodulator. I have since replaced the X demodulator, 1st video amplifier, the Horiz. Damper, Focus Rectifier, HV Rectifier and Horiz Output Tube.

With the extra drive, the blooming effect has reduced and focus has improved. The picture is improving and with a little more work it should be quite acceptible.

I have attached some photos of it working this evening. Note the dolly which helps me rotate the heavy cabinet. I have made up a bunch of extender cable so that I can readily pull the chassis and hook it up to the CRT for further technical investigations.

Wow, thats a beautiful picture.The convergence looks really good!

Wow, thats a beautiful picture.The convergence looks really good!

Thank you. Yes, I am pleased with the incremental improvements over the past few weeks. The convergence comes in very well on this set. I have had two roundie Zeniths and a CTC10 and CTC11 in the past and curiously this one has the best convergence.

The chroma demodulator alignment is still required. But I am pleased with the incremental improvements in the picture quality gained over the past few weeks.

That picture is looking really nice, and I really like that cabinet. I can't get over how clean the chassis looks on that set.

That picture is looking really nice, and I really like that cabinet. I can't get over how clean the chassis looks on that set.

Thanks. The picture is looking better. The set doesn't appear to have been used that much, hence it is remarkably clean and original.

I feel the set has two problems which may be inherent in the CTC-5 design: limited HV beam current and poor video amplifier frequency response. When I crank up the brightness to provide "reasonably" bright picture highlights, the picture starts to bloom and the horizontal scan begins to shrink. The 21AXP22A has plenty of life and perhaps the limited beam current has helped preserve it! The RCA service notes shows a drooping video amplifier frequency response which I expect makes the picture appear slightly soft. I recall Nick discussing the former and Wayne discussing the later with their respective CTC5's. I also recall getting a much "snappier" picture with a CTC10 and CTC11.

This particular CTC5 was a curious find. It came from an older house not far from downtown Toronto. I purchased it from I believe the grandson of the original owner.

When this set was bought new in Toronto in late '56 or early '57, it would be another 10 before the first Canadian color broadcast by the CBC. The set is fitted with a UHF tuner which is extremely unusual for Canadian sets in 1956-7. The first Canadian UHF channel was TV Ontario which signed on in about 1970.

WGR-TV (NBC) would have the source for Toronto of most color programming and it was at that time on channel 17, one of the first US UHF channels. (WGR reverted to channel 2 in 1958). The CBS affiliate, WBEN-TV channel 4 I expect was the only other source of color.

WOW an owned and operated that learned that UHF was a big money loser on Channel 17 ............:scratch2::smoke::scratch2: