View Full Version : Canadian RCA CTC-39X "Instant-PIC"
hyperlag 09-03-2021, 05:51 PM Hello Everyone,
First time poster here and my first TV and tube restore. I found a farm fresh Canadian CTC-39X recently. After replacing some cooked fuses I got it to power on. But curiously it will only demod sound and give a picture if "Instant-PIC" is turned on. I kind of guessed at the Sam's folder I needed and got 1284-2, but the model in there does seem to have this feature. Without it I get some low power draw when switched on, with it I get a huge inrush then quickly it settles under 300W where I expected it to sit with a funky raster and sound.
I first assumed it was an "instant on" type scenario, but there is no draw when the set is switched off. So I don't think the filaments are being kept warm or anything. Does anyone know what this feature is? I'm a first timer at this, so any tips would be appreciated.
That includes any other tips for what I should look into trying down for the wonked out vertical I am getting.
hyperlag 09-03-2021, 05:53 PM This is a bit of an end of the line/spare parts kind of deal so here is the model in case it helps.
hyperlag 09-03-2021, 05:56 PM I imagine I am also going to be tracking down a weak tube or hunting bad caps as well? I couldn't get the vertical much better than this in the few minutes I was brave enough to run it with a bypassed breaker on a current loop meter...
A few notes.
Sams never listed Canadian sets but usually there were US versions
that were near identical.
The CTC39 was almost the same as the CTC38 but I dont remember
the major difference. I dont remember any CTC38 with instant on.
I do not know the feature your set has. It sure sounds like "instant on".
Most sets with instant on will have gang on/off switch. Some would
have two or 3+ switches on the one on/off SW. Normally the set WILL draw
current when off UNLESS there is a standby/vacation SW involved.
Look at the on/off & see if it has multy switches instead of the usual
SPST switch.
BTW there is someone offering Can manuals on the list. do a search.
73 Zeno:smoke:
LFOD !
Jeffhs 09-04-2021, 04:13 PM The instant-on feature on TVs of the '70s was a good idea, but a major disadvantage was the TV would still draw a small amount of current even when the set was turned off.
I personally would disable the instant-on feature, in the interest of saving electricity. I would also get in the habit of unplugging the TV from the wall socket if the user would be away from home any length of time, say on vacation. One other problem which occasionally occured with instant-on televisions was the instant-on diode would short after a lightning strike; this had the same effect as jumpering the set's power switch, which would keep the TV on as long as the cord was plugged in. This sometimes happened late at night, after the set's owner went to bed; the person was not even aware of the problem until he/she woke up the next morning and found the TV on, showing a program on the last channel viewed, or a white screen full of snow (and white noise in the speaker) when the TV station signed off for the night (this, of course, was before 24-7 TV started in the US).
This problem could be cured, sort of (!), by removing the shorted instant-on diode from across the power switch. Of course, however, this eliminated the instant-on feature, but by the end of the '70s this feature was viewed as an energy-waster anyway, so I doubt if it was missed much, or at all.
BTW, I was not aware, until now, that RCA even made television receivers for the Canadian TV market, since RCA was an American company. What was the difference, if any, between American RCA-branded televisions and those built, and marketed, in Canada?
hyperlag 09-04-2021, 05:34 PM I played around with it a bit today and I think everyone is correct that this is instant on, but not how it is typically setup. As far as I can tell, the master on / volume pot switches the main transformer input. The instant PIC has an on and off button, but neither can bypass the master power. When "Off", the filament heater stay on (if the master power switch is on) but nothing else. Pressing the On button, sets it to full power and I get sound/picture. Sort of the best of both worlds, given you can override the instant on with the normal power switch. I do plan on never leaving it plugged in and have been considered putting an in-line power switch right on the cord.
As for the difference with Canadian sets... I'm not really sure to be honest. So far it just seems like chassis are numbered slightly different and the TVs they go into never 100% line up with service manuals from the US. For example, this Instant-PIC function wasn't included in the CTC39X Sams folder I selected that appeared to be the closest match.
I'm really new at this stuff and have no way to measure high voltage. So pray for my flyback!
hyperlag 09-04-2021, 05:43 PM Oh, one oddball thing about this Canadian model vs the US one is that my picture tube model lines more up with a Sylvania, but is branded RCA (and is original / lowish hour I think). As well, the original tubes left in there are made in Canada. Don't see that stamped on stuff anymore!
Jeffhs 09-04-2021, 11:29 PM Hello Everyone,
First time poster here and my first TV and tube restore. I found a farm fresh Canadian CTC-39X recently. After replacing some cooked fuses I got it to power on. But curiously it will only demod sound and give a picture if "Instant-PIC" is turned on. I kind of guessed at the Sam's folder I needed and got 1284-2, but the model in there does seem to have this feature. Without it I get some low power draw when switched on, with it I get a huge inrush then quickly it settles under 300W where I expected it to sit with a funky raster and sound.
I first assumed it was an "instant on" type scenario, but there is no draw when the set is switched off. So I don't think the filaments are being kept warm or anything. Does anyone know what this feature is? I'm a first timer at this, so any tips would be appreciated.
That includes any other tips for what I should look into trying down for the wonked out vertical I am getting.
How long did your set work after you replaced the blown fuses? If a fuse blows, you can be sure there is a reason, such as a short circuit in the set somewhere, from the power supply forward.
Whatever you do, however, do NOT bypass a blown fuse or use an overrated fuse just to get the TV to operate again. When a fuse blows, as I said above, you can be sure there is a short or some other problem which caused the fuse to blow and open the circuit. If you bypass the fuse or, worse, use an overrated fuse to get the set working again, you are asking for trouble if the condition which originally blew the fuse is still there. I read years ago, I forget where, of a rule of thumb which says allow yourself one, and only one, new fuse when you are troubleshooting a TV or other electronic device. If the replacement fuse blows, you can be sure there is a short or an overload somewhere in the set which must be cleared.
hyperlag 09-05-2021, 03:52 AM The fuses never actually reblew. It looks to have had a breaker rust then short out to the chassis ground. That caused some havok in the power section. To get it running while I wait for my nos breaker I have underrated fuses patched in place. I also throw a hall effect sensor on the wire and keep a killawatt running to to watch current entering and leaving the main transformer.
hyperlag 09-05-2021, 03:56 AM Also, forum member Roni hooked me up with some Canadian schematics. I think I was correct in my assumptions about how this weird instant on works. S104 is the gang switch in question. I've been treating it more like an onboard variac to warm it up and limit the inrush.
Popester 09-05-2021, 09:37 AM Nice set and welcome to the forum. Jug looks to be in good shape. The picture of your flyback looks like it hasn’t gotten to warm. Some slight drip page of wax but it looks normal. Might want to eventually check the horizontal output current and adjust the efficiency coil. Minimum current tends to insure the flyback won’t be over stressed. Was always to be checked and adjusted if needed when HOT tube was replaced.
hyperlag 09-05-2021, 12:27 PM Nice set and welcome to the forum. Jug looks to be in good shape. The picture of your flyback looks like it hasn’t gotten to warm. Some slight drip page of wax but it looks normal. Might want to eventually check the horizontal output current and adjust the efficiency coil. Minimum current tends to insure the flyback won’t be over stressed. Was always to be checked and adjusted if needed when HOT tube was replaced.
What sort of meter would you recommend for that? I was thinking about getting a Pomona or something for checking the HV on the tube. I've never really considered if my dinky multi-meter could handle being in line for current. I do have one of those hall-effect clamps though.
I'm still getting used to the scale of voltages and currents in these things versus the digital stuff I'm used to. haha
hyperlag 09-05-2021, 12:28 PM And yeah, the fly impressed me too. I have a feeling this set has been in storage a long time. The 75 ohm connection had never been bridged and there really wasn't much or maybe any OTA out in the country where I found it.
maxhifi 09-05-2021, 12:44 PM The instant-on feature on TVs of the '70s was a good idea, but a major disadvantage was the TV would still draw a small amount of current even when the set was turned off.
I personally would disable the instant-on feature, in the interest of saving electricity. I would also get in the habit of unplugging the TV from the wall socket if the user would be away from home any length of time, say on vacation. One other problem which occasionally occured with instant-on televisions was the instant-on diode would short after a lightning strike; this had the same effect as jumpering the set's power switch, which would keep the TV on as long as the cord was plugged in. This sometimes happened late at night, after the set's owner went to bed; the person was not even aware of the problem until he/she woke up the next morning and found the TV on, showing a program on the last channel viewed, or a white screen full of snow (and white noise in the speaker) when the TV station signed off for the night (this, of course, was before 24-7 TV started in the US).
This problem could be cured, sort of (!), by removing the shorted instant-on diode from across the power switch. Of course, however, this eliminated the instant-on feature, but by the end of the '70s this feature was viewed as an energy-waster anyway, so I doubt if it was missed much, or at all.
BTW, I was not aware, until now, that RCA even made television receivers for the Canadian TV market, since RCA was an American company. What was the difference, if any, between American RCA-branded televisions and those built, and marketed, in Canada?
RCA Canada was originally in Montreal, and then moved to Ontario. Back before NAFTA, Canada had locally made products in pretty much every category. The Canadian sets were often inspired by US sets, but there were also unique models, and some parts differences. For example, I have a 12" B&W new vista which is Japanese made by Sharp. My Canadian CTC 38 is full of Japanese made RCA branded tubes, and the picture tube was made in Canada. The cabinets are assembled with square drive Robertson screws (a tell take sign of a Canadian product). And the record changes are almost always Garrard or sometimes BSR. They never used the US built RCA changers.
The best meters for tuning coils are usually old school quality VOM's
or VTVM's See the RCA Volt-Ohmist or Simpson 260. Being able
to see the slow swing on a real meter is much better than a digi meter
flashing away. The dip will show up nicely :banana:
FBT wax looks normal considering the FBT looks OEM & probably was
running 10-20 yrs.
When you measure the H. out current do it by the book. Even running the
brightness a little high can through off the reading. Be sure to do grey
scale, kine bias, HV adj etc first.
73 Zeno:smoke:
LFOD !
What sort of meter would you recommend for that? I was thinking about getting a Pomona or something for checking the HV on the tube. I've never really considered if my dinky multi-meter could handle being in line for current. I do have one of those hall-effect clamps though.
I'm still getting used to the scale of voltages and currents in these things versus the digital stuff I'm used to. haha
Electronic M 09-05-2021, 07:28 PM Generally the cheapest meter that can do 250mA or higher will work fine. I used to have the cheapest Radio Shack VOM (bought shortly before they closed most stores) as my main H out cathode current meter. Eventually I got a vintage Seco tester that has inline tube sockets that you plug in between the tube and chassis to connect the meter and that supplanted the shadio rack meter.
Hi Hyperlag.I just read your posts and looks like the service info I sent you is correct for that set.your chassis number ctc 39xz is covered by my RCC manual.I was worried it wasn't close enough.clean set for a barn find. RonL
Jeffhs 09-06-2021, 12:47 PM RCA Canada was originally in Montreal, and then moved to Ontario. Back before NAFTA, Canada had locally made products in pretty much every category. The Canadian sets were often inspired by US sets, but there were also unique models, and some parts differences. For example, I have a 12" B&W new vista which is Japanese made by Sharp. My Canadian CTC 38 is full of Japanese made RCA branded tubes, and the picture tube was made in Canada. The cabinets are assembled with square drive Robertson screws (a tell take sign of a Canadian product). And the record changes are almost always Garrard or sometimes BSR. They never used the US built RCA changers.
I agree with your statement that modern Korean, Japanese, etc.-made radio-phonographs or even three-way devices used Garrard or BSR record changers. (I knew someone years ago who had a very low opinion of BSR record changers.) Some years ago, I had a Zenith four-function (AM/FM stereo, cassette, phono, 8-track player) entertainment unit which had a BSR 3-speed record changer. The changer in mine did not play 16 RPM records, as by the time this system was made and marketed the old 16-RPM records had been obsolete for many years.
BTW, eight-track stereo tapes had been obsolete for decades as well by the time these Zenith systems came on the market; in fact, I don't think I used the 8T in mine more than a small handful of times, if that many, in the 17 years I owned the system. In fact, again, IIRC, I only owned one (!) eight-track tape in my entire life, even though I am old enough, at 65, to remember 8-track tapes (my former, now late, stepmother had an 8-track tape player in her 1972 Plymouth Duster automobile).
Popester 09-06-2021, 01:56 PM Others already chimed in about a meter but I agree an old style analog meter VTVM or VOM are best done with a meter that you can see the dip happen as Zeno mentioned. Digital meter will do the job but they are slightly harder to interpret the result. I think us old guys just prefer analog. Still wearing a old fashioned watch on my wrist too lol .
hyperlag 09-09-2021, 01:00 PM So I got dug into the set again and have discovered a broken bracket on the yoke. As a result, my convergence and purity are all out of wack. I played around with it and the magnets but no real luck. Basically every picture setting was also played with by the previous owners as well, so I guess I'm doing a full setup on it.
Anyone have any tips? Sam's is a little cryptic and the shango066 videos I've watched don't explain connecting resistors to the grid and how to move the tabs. I'm kind of hoping to just get it good enough to play with a little, as the bracket looks like a longer term project to get out and replace...
Thanks!
damen 09-09-2021, 08:21 PM That broken bracket looks like the yoke clamp. When they would corrode and break they would sometimes damage the fine wires going to the convergence coils. Broken wires on those coils would cause certain convergence controls/coils to have no effect when you adjusted them.
Its just the yoke clamp. Just be sure the missing piece is not
laying on the chassis ! The clamps on RCA yokes & blue lateral , purity
ring ass's tended to rot away. Replace with any clamp from a
90 deg delta CRT. Dont use an OTC clamp for a car etc. It may be
magnetic.
For CRT set-up follow the Sams til you get stuck then ask. If you
mark where things were you can go back to the start if needed.
Remember a few things.
1) Most of the adjustments are for the CENTER of the screen.
2) Ignore the 12 adj on the conv board till the end.
3) On big sets its better to lay across the set & look directly at the
screen.
4) For your first few set-up jobs a DOT pattern is best. After a few you
can do it by eye.
5) Be sure the TV is getting the best B&W pic you can get first !
enuf fer now
73 Zeno:smoke:
LFOD !
hyperlag 09-11-2021, 03:34 AM Its just the yoke clamp. Just be sure the missing piece is not
laying on the chassis ! The clamps on RCA yokes & blue lateral , purity
ring ass's tended to rot away. Replace with any clamp from a
90 deg delta CRT. Dont use an OTC clamp for a car etc. It may be
magnetic.
For CRT set-up follow the Sams til you get stuck then ask. If you
mark where things were you can go back to the start if needed.
Remember a few things.
1) Most of the adjustments are for the CENTER of the screen.
2) Ignore the 12 adj on the conv board till the end.
3) On big sets its better to lay across the set & look directly at the
screen.
4) For your first few set-up jobs a DOT pattern is best. After a few you
can do it by eye.
5) Be sure the TV is getting the best B&W pic you can get first !
enuf fer now
73 Zeno:smoke:
LFOD !
Thanks for the tips. Are there any online sources for test patterns you recommend? I'm stuck feeding them in from a computer/VCR for now.
Telecolor 3007 09-11-2021, 04:40 PM "Instant PIC" meant that the filament of the C.R.T. was kept in permanent heating?
Electronic M 09-11-2021, 06:06 PM "Instant PIC" meant that the filament of the C.R.T. was kept in permanent heating?
On a set like that where the chassis uses signal tubes those signal tubes would need heater power too.
old_tv_nut 09-11-2021, 09:32 PM "Instant PIC" meant that the filament of the C.R.T. was kept in permanent heating?
Yes, permanent heating, but at reduced power.
Motorola wanted "instant on" for their first small-screen all-transistor black and white TVs, but didn't want to buy the multipole power switch required. I came up with a scheme where one of the power transformer windings would buck the main winding when the set was "off." It worked, but unfortunately, the channel number back light was an incandescent bulb that came off the same transformer. So, my idea was adopted only after some executives took prototypes home to satisfy themselves that the channel light was not visible in a dark bedroom after your eyes had adjusted.
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