View Full Version : 1962 Zenith 19" b/w SC300
This set mostly works (even the remote), except for the super weak CRT (It had a brightener on it, and won't even budge the needle on the tester at 8V), and slightly weak horizontal sync. It takes the 19AJP4, but I have a good 19CQP4 I pulled out of another Zenith. The only difference between the two according to the tube manual is the current rating, which shouldn't matter with a parallel filament wired set anyway. I'll do the usual recap of electrolytics, look into the horiz sweep, swap that picture tube, and this set (unlike that Philco I've been working on) should be an easy repair.
Jon A. 05-08-2014, 08:27 PM B&W isn't my thing, but I gotta love the channel indicator on those.
I have a lot of these b/w Zeniths and the cool looking clear red light up channel changer button is I think unique to this model.
I swapped the crt, didn't do any other repairs, and this set is working pretty good already.
Jeffhs 05-09-2014, 12:41 AM Congratulations. Your set's picture looks great, and may look even better once you recap the chassis. This set is another excellent example of the former Zenith Radio Corporation's slogan at the time (in this case, early 1960s), "the quality goes in before the name goes on." :thmbsp:
I used to love working on the old tin can Zeniths. Always
easy to fix & came out great. Owned a few pre '64's myself.
Imagine if they made everything like that again............
73 Zeno:smoke:
Rod Beauvex 05-09-2014, 10:39 AM Any chance of a better pic of the channel knob? It looks kind of cool.
dieseljeep 05-09-2014, 11:25 AM I used to love working on the old tin can Zeniths. Always
easy to fix & came out great. Owned a few pre '64's myself.
Imagine if they made everything like that again............
73 Zeno:smoke:
Circuit-wise, they were identical to the larger screen table models and consoles. It was built on a smaller chassis.
Motorola built a portable, similar to that one, and was as good. They used the same chassis in the larger sets, as well. :thmbsp:
Jon A. 05-09-2014, 01:24 PM Any chance of a better pic of the channel knob? It looks kind of cool.
Look here:
http://videokarma.org/showthread.php?t=261240
Rod Beauvex 05-16-2014, 08:21 AM Excellent.
I've been working on this set some more. It produces an excellent picture, with just one minor problem. Notice how in the picture I posted, the picture is curved on the bottom. All the lines towards the bottom of the screen have that curve in them where the middle is higher up than the edges. (But there's nothing wrong with the vertical size, I just turned it down so the bottom edge of the picture could be seen to make the effect more visible.) I'm wondering if this effect has to be due to the yoke itself - I have another I'm going to try tomorrow.
Jeffhs 05-17-2014, 01:23 AM The pictures of this TV in your other posts do not show that curvature. Is this something that just started recently? I would suspect hum getting into the vertical deflection circuits, but you said you replaced the electrolytic filter capacitors so I guess that isn't the problem--unless the vertical oscillator or output tube has slight heater-cathode leakage, not enough to cause a visible hum bar, but enough to distort the sweep. My best guess as to why this distortion does not show in the other pics you posted is that you had the vertical size control set for normal sweep, so that any raster distortion would be behind the lower edge of the CRT mask and, therefore, not visible.
It was doing it earlier as well before I recapped, but the effect was really only noticeable on the bottom on the screen in the corners if you looked closely enough to see the individual lines, or if you pulled in the vertical size like I did (Or if you kept the size full, but adjusted the vert hold so a blanking bar moved slowly down the screen, you could see it get curvy when it got towards the bottom.)
Today I tried two different yokes, several of those horiz width sleeves put in both ways, spent a long time messing with those centering ring magnets, and removed that piece the yoke bolts to and put it in upside-down (as far as I can tell it can go either way with no difference - but I tried it anyway). I made sure the yoke was exactly in the center of the tube neck...
Careful adjustment of the yoke could improve the problem, but not make it completely go away. Finally I just put the original yoke back, adjusted it the best I could, and said that was good enough. Then I turned the tv right side up, instead of on its side (I rotated the 2 pictures above) ... and that fixed it?! I can't explain it, but the picture does that when the tv is sideways, but not when it's sitting normally.
Anyway, tomorrow I'll put the cabinet all back together. That just leaves 2 more TVs I want to fix this summer, the '61 RCA 19" remote b&w, and '59 Admiral 17" remote b&w...
Now this Zenith is back together, and working. Next I'm going to start on that Admiral.That last pic shows the knobs, so you can see how the channel indicator works.
jstout66 05-19-2014, 06:32 AM Hey Adam, Nice Zenith!
I might have a NIB triad FLY for your RCA if you want a spare. If you know the RCA or Triad number yours takes, I'll check.
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