View Full Version : Sweet 1974 Sylvania Color set


TUD1
12-21-2015, 10:43 PM
I got this with the VCR haul this weekend. When we tested it, it seemed to have convergence issues, but when I tested it at home the picture was very good. The only thing was that the vertical was a little off. I adjusted the vertical height and that solved the problem. This will replace my 1979 Quasar as my daily driver.

dishdude
12-22-2015, 12:09 AM
Looks nice! I like it.

zeno
12-22-2015, 12:27 AM
IIRC it has a small convergence board that got cold joints.

73 Zeno:smoke:

TUD1
12-22-2015, 12:28 AM
I had a suspicion that this TV has the dreaded "Instant On" feature. My suspicion was confirmed when I turned the set on and the picture came up in three seconds. I really want to disable this before I put this TV into regular use. Does anyone know how to do that?

tvtimeisfun
12-22-2015, 12:54 AM
I know that some tube sets had a switch that cut that feature off magnavox was one of those sets..Timothy

radiotvnut
12-22-2015, 01:29 AM
We'd need to see a schematic to determine how the "instant on" is accomplished and if there is an easy way to defeat it. The easiest thing to do would be to operate the set from a power strip.

Up until about '87, one of the local hospitals had sets very similar to this in the rooms. The ones they had used the E-08 chassis that used a power transformer and three big plug-in modules. The CRT was a delta gun tube. They had a wired remote and a motorized tuner.

Electronic M
12-22-2015, 01:50 AM
I had a suspicion that this TV has the dreaded "Instant On" feature. My suspicion was confirmed when I turned the set on and the picture came up in three seconds. I really want to disable this before I put this TV into regular use. Does anyone know how to do that?

If the power strip method don't float your boat, get a schematic for it and examine the CRT heater wiring...
This set may have a "vacation" or "instant-on", etc. switch to disable it (look for it on the back).

DaveWM
12-22-2015, 09:04 AM
get one of those remote switched outlets sold for Christmas lights. its a small remote that has 3 buttons, for 3 different remotes. Then plug in the tv to it, leave it on (I assume it has a manual switch and not a logic switch). This way you can defeat the instant on AND have a remote to turn it on. I use this setup on my SS Avanti, works great.

tom.j.fla
12-22-2015, 10:29 AM
Hello, This set if its' a 19 inch set uses a E-21-_ _ (fill in the number) chassis. If the number is over 10 it will have a fast start crt powered by a 3 turn winding on the flyback. If that is the case just enjoy as you are not doing in the crt. All the best,Tom

TUD1
12-22-2015, 05:45 PM
Well, I got this TV all set up with my new converter box and it was working perfect for about 2 hours. Then, all of a sudden, the focus crapped out. Any ideas? There is no sharpness/focus adjustment on the outside of the set.

tom.j.fla
12-22-2015, 07:08 PM
What is the model,chassis number? If the set has a quad-line CRT then focus is generated by the tripler most likely dirty or open pot on the chassis. If the CRT is RCA type inline gun then trouble is most likely in the intergrated hi voltage transformer. Again really need the model & chassis number to help you. All the best,Tom

TUD1
12-22-2015, 07:12 PM
OK Thanks. Sorry I haven't gotten that yet. I've been hassling with that converter box.

Findm-Keepm
12-22-2015, 07:14 PM
Well, I got this TV all set up with my new converter box and it was working perfect for about 2 hours. Then, all of a sudden, the focus crapped out. Any ideas? There is no sharpness/focus adjustment on the outside of the set.

If you want help, you're gonna have to give us some meat - model, chassis number to start - it's the number one reason I skip threads - no chassis or model number, no help from me.

Sams, manufacturers and cross references all use the chassis or model number. There isn't a single listing for "1974" under Sylvania in any cross reference. These aren't cars - you have to give up the model and chassis, in writing, so the search will work. Taking a photo of a model/chassis number doesn't work with search.

radiotvnut
12-22-2015, 07:54 PM
Looks like it's a CX4161W (Chassis E08) in Sams 1481-2.

It's the same chassis that was in the hospital sets that I mentioned above. It will use a delta gun tube. For the HV/focus, it will use a tripler and a focus control assembly. I've seen the tripler go bad in these and I've also seen the focus control assembly arc and burn.

TUD1
12-22-2015, 07:57 PM
The Model No. is CX4161W. The chassis ID no. is E080103-4213288.

Findm-Keepm
12-22-2015, 08:06 PM
Looks like an E-081/82/83 chassis....great sets.

Focus problems could be focus pot, CRT or tripler. Do you have an HV probe?

TUD1
12-22-2015, 08:23 PM
Well I found the focus adjustment, put the cover back on, and it wasn't 5 seconds before the brightness went out the window. I did not adjust a single thing while the back was off the TV. Brightness and contrast have no effect.

No HV probe here.

TUD1
12-22-2015, 08:39 PM
I moved the TV around a bit and got the brightness to come back, then I adjusted the focus. The focus is maxed out and it's still fuzzy, but it's better.

About three minutes later and the brightness is dead again.

Electronic M
12-22-2015, 09:09 PM
Well I found the focus adjustment, put the cover back on, and it wasn't 5 seconds before the brightness went out the window. I did not adjust a single thing while the back was off the TV. Brightness and contrast have no effect.

No HV probe here.

^Text book failure of the monochrome video chain. Somewhere between the place chroma splits from the monochrome in the signal chain and the element of the CRT driven by the monochrome signal you are intermittently loosing the video signal.

You need a schematic, and either an oscilloscope, or a purpose made TV test pattern generator with a variable level video output to trouble shoot that.

bgadow
12-22-2015, 10:02 PM
I would try playing with the setup switch (maybe the one at the bottom, back of chassis.)

As I recall, the 74 Sylvania I have had a similar intermittent. Right off the top of my head I can't remember the fix, but it was something easy like that.

sampson159
12-22-2015, 10:28 PM
bryan is right.those sets had problems with the service switch.the brightness would fade leaving you a black screen.deoxit and that should take care of that issue.this sets takes a 523 tripler.wouldnt be a bad thing to replace this too.pretty good sets.

TUD1
12-22-2015, 10:59 PM
That makes perfect sense. When I took it apart, I accidentally hit that switch when I put the cover back on. I'll try that.

The service switch was the problem, and now the brightness is back. The focus is still way off, even with the control maxed out. Before the focus went haywire, the control was only halfway and the picture was near perfect. I was informed that I should clean the focus pin on the CRT if it's corroded, so I'll do that tomorrow.

radiotvnut
12-23-2015, 01:51 AM
Yes, check the focus pin. If this is good, check the focus control and the parts associated with it. If this is good, the focus divider inside the tripler is likely bad (triplers were a common failure in these).

Regarding the chassis number, that one looks more like an E21; but, I'm pretty sure the ones in those hospital sets were E08 and I know they were a 3-board modular chassis, with a delta gun CRT.

TUD1
12-23-2015, 10:58 AM
Thanks for the info. Here is a picture of the TV in the very small amount of time that the converter box and the TV were working perfectly.

TUD1
04-02-2017, 02:17 PM
Pulled this TV back out today, since I thought it would look cool on the cart I got yesterday. This set, having an inline gun, has razor sharp focus and outstanding colors. I put it up back in 2015 because it has a slight problem with the color demodulator IC. On faces, the color will sort of "roll" from pinkinsh to yellowish. I haven't noticed the problem anywhere other than on faces. Found a newspaper ad from 1974 with this model on it. I didn't really believe that it was a 74 with that inline tube, but I'm pretty sure it is now.

Jon A.
04-02-2017, 03:56 PM
Pulled this TV back out today, since I thought it would look cool on the cart I got yesterday. This set, having an inline gun, has razor sharp focus and outstanding colors.
I think it's just an inherent trait of Sylvanias of that era. My '79 delta Superset must have had the best picture of any of my sets until the tripler blew. That was replaced, but then a solder pad fell off the focus control and I'm still trying to track one down, sigh.

TUD1
04-02-2017, 05:16 PM
Based on what I've seen and heard, Sylvania was slightly ahead of all the others on their phosphor formulation. I've seen some 60's Sylvania sets give a super bright, super vivid picture. I think it may have had something to do with Sylvania being a big light-bulb manufacturer. Maybe they had lots of experience in phosphor development from working with fluorescent and mercury vapor lamps. I have a rebuilt Sylvania Color Bright tube, and as you can see, even it gives a very impressive picture. Here it is in my RCA CTC-40.

TVTim
04-02-2017, 06:19 PM
That is a nice looking set.

TUD1
04-03-2017, 12:40 AM
Thanks, I thought so too. That's why I went and dug it back out of storage. It looks really nice on that cart, too. Just wish I could find a new demodulator IC.

zeno
04-03-2017, 03:39 PM
Thanks, I thought so too. That's why I went and dug it back out of storage. It looks really nice on that cart, too. Just wish I could find a new demodulator IC.

Thats a damn nice natural pix.

Dont remember which IC but one of the IC's went disco by the
mid 80's. Pissed off quite a few customers & us too. Trouble was those sets
held up real good. The E08 as good as Zeniths but the Super Set 19"
modular chassis suffered bad CRT's just like the consoles. When new
the pix was spectacular.
We mined the junk sets for the IC's but never had enuf........

73 Zeno:smoke:
LFOD !

bgadow
04-03-2017, 10:40 PM
Post the part number for that IC when you get a chance.

TUD1
04-04-2017, 01:06 AM
Hopefully tomorrow I'll get around to doing that. I was just watching The Late Show with Stephen Colbert, and if you've ever watched that show, there's a lot of different colors and scene changes. All the different colors drove the Sylvania's color demodulator crazy. It was as if a minion was constantly adjusting the tint control, and sometimes, turning the color control to max and then back down again. Here you can get an idea of what is happening. Flesh tone is correct, but the ocean is both green and blue.

DavGoodlin
04-07-2017, 04:56 PM
Post the part number for that IC when you get a chance.
Sylvania part numbers for ICs and transistors went something like 13-xxxxxx

edit: I have a schematic which shows a sylvania part # 15-37704-1 IC std 14 pin DIP with a block diagram having two "demod" and three color difference amps. Looks rather simple

old_tv_nut
04-08-2017, 12:04 AM
I'm not sure I follow what's going on with the color, so forgive me for thinking out loud. If this set uses an IC for the color section, and it's basically working but varying, it could be the IC, but it could also be the control voltages, including intermittent connections, or problems with bad filter caps if the controls supply DC voltages rather than video signals. Also, does this set have some sort of automatic color switch that could be intermittent?

old_tv_nut
04-08-2017, 12:13 AM
Based on what I've seen and heard, Sylvania was slightly ahead of all the others on their phosphor formulation. ...

You've heard right. Sylvania was always finding a better processing sequence for their phosphors - the precise formula, heat treatment, grain size, slurry thickness, you name it. As I have posted elsewhere here, when I was at Motorola, Sylvania came up with a thick slurry that was brighter, but when Motorola tried to duplicate it, they had trouble due to swirl marks developing in the screens. The thicker slurry apparently needed a different swirl pattern/rate that the Motorola deposition machinery wasn't designed to do.

DavGoodlin
04-08-2017, 08:46 AM
As I recall, Sylvania had a CRT plant first in Emporium, PA then later a modern plant in Seneca Falls, NY. Thier color bright 85 replacements outsold RCA at our local parts house. i usually chose RCA for an RCA set, IIRC.

The RCA CRT plant in Lancaster PA (here I am) and Marion Indiana were also developing a better phosphor

All these locations are nowhere near big cities. Those Engineer-Physicist types hated cities and I can understand why.

Unfortunately all the old timers I meet from this RCA plant worked in power tubes and orthicons.

old_tv_nut
04-08-2017, 12:10 PM
...

Unfortunately all the old timers I meet from this RCA plant worked in power tubes and orthicons.

Well, not so unfortunate if you are interested in orthicons. I would love to know the details of how the thin glass orthicon targets were created - like a thin glass bubble, but perfectly flat.