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  #16  
Old 12-05-2015, 07:41 PM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by zeno View Post
It may be an error in Sams. If its a say 33 ohm & you add
a zero its a 330 ohm..........

For now just check for APX 95 vac on pin 7 of tube V7.
You do not want to put a 33 ohm in if its a 330 ohm.
NOT good for the filaments............

Why get a pix first ?
1) to be sure you got a good CRT. Even if it tests good it still can be bad
& visa versa.
2) check to see that all MAJOR parts are OK. Even 40 yrs ago
you couldnt get some of this stuff.
3) you learn by troubleshooting NOT shot-gunning
4)re-caps need to be done a few at a time followed by a test.
If you do something wrong its easier to find if you just gotta
look at a few things. Nothing worse than finding a self induced
problem. Sends techs running if its "been somewhere else"
& never fixed. And you never get the truth out of the
customer !!

good luck
Zeno
33 or 36ohms has to be right! 36 ohmsX 600ma=21.6 drop. 21.6+95=117volts, approx.
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  #17  
Old 12-05-2015, 08:58 PM
fixmeplease fixmeplease is offline
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Wow, thanks all for the suggestions and the web link. I'll digest it overnight and try to answer as well as I can tomorrow. I'll try to read that 33/330? resistor outside in the sunlight too as it is faded. Again, thank you.
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  #18  
Old 12-06-2015, 11:07 AM
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Marco-nix Marco-nix is offline
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Quote:
Originally Posted by zeno View Post
It may be an error in Sams. If its a say 33 ohm & you add
a zero its a 330 ohm..........Zeno



You are right. Over my schematic reading, I realized that publications from SAMS are often wrong. So now I am wary of what there are sometimes in the schemas. nothing better than a regular of repair of TVs to give you the real stuff, the real values of each piece...
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  #19  
Old 12-06-2015, 11:17 AM
fixmeplease fixmeplease is offline
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I couldnt read the resistor well until I took pictures of it, then it shows them fairly well except for the last number. Top row A43(K or X) 402. Bottom is W.G.33 and the last one could be a 4. You may be correct about the sam being wrong. It tested at 356 this morning with a DVM. So for now Im guessing i should use it?
I'll order the coating product mentioned. Thanks again!
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  #20  
Old 12-06-2015, 12:19 PM
dieseljeep dieseljeep is offline
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Originally Posted by fixmeplease View Post
I couldnt read the resistor well until I took pictures of it, then it shows them fairly well except for the last number. Top row A43(K or X) 402. Bottom is W.G.33 and the last one could be a 4. You may be correct about the sam being wrong. It tested at 356 this morning with a DVM. So for now Im guessing i should use it?
I'll order the coating product mentioned. Thanks again!
I looked the schematic in Beitmans. The heater string is the same as in Sams, showing a 36 ohm, 20 resistor. Ohm's law proves that the resistor has to be a value between 30 and 40 ohms, otherwise the tubes wouldn't lite at all.
Is your meter auto-ranging or it doesn't display the decimal point.
Your earlier posts, mentioned that the tubes lit, when you brought it up on line, but all you got was a squeal, which indicated possible bad electrolytics.
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  #21  
Old 12-06-2015, 12:59 PM
old_coot88 old_coot88 is offline
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There's a quick & dirty way of measuring 'Gravel Gerties' of unknown value. Crack it in two at the halfway point and measure the side that still has continuity, and multiply by two.
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  #22  
Old 12-06-2015, 02:24 PM
Paul Knaack Paul Knaack is offline
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Quote:
Originally Posted by dieseljeep View Post
33 or 36ohms has to be right! 36 ohmsX 600ma=21.6 drop. 21.6+95=117volts, approx.
330 ohms at .6 amps would drop 198 volts
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  #23  
Old 12-06-2015, 03:23 PM
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zeno zeno is offline
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Quote:
Originally Posted by old_coot88 View Post
There's a quick & dirty way of measuring 'Gravel Gerties' of unknown value. Crack it in two at the halfway point and measure the side that still has continuity, and multiply by two.
Great tip !! 40yrs in the biz & I never heard it. I tip
my hat 2 U.

Oh BTW we called them bricks up here.....

73 Zeno
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  #24  
Old 12-06-2015, 04:44 PM
fixmeplease fixmeplease is offline
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Quote:
Originally Posted by dieseljeep View Post
I looked the schematic in Beitmans. The heater string is the same as in Sams, showing a 36 ohm, 20 resistor. Ohm's law proves that the resistor has to be a value between 30 and 40 ohms, otherwise the tubes wouldn't lite at all.
Is your meter auto-ranging or it doesn't display the decimal point.
Your earlier posts, mentioned that the tubes lit, when you brought it up on line, but all you got was a squeal, which indicated possible bad electrolytics.
My meter has a 200 setting, then the next is 2000. It goes past the 200 setting (displays 1), and when I set it to 2000, it displays .356

Every tube lit up that I could see, with one in the can that I couldnt see.

I am lost about the cracking one in two idea.
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  #25  
Old 12-06-2015, 04:59 PM
fixmeplease fixmeplease is offline
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OK, I dug out my analog meter and hooked a 330 ohm resistor to it and calibrated it to that. When I put the resistor in question on it, its reading about 68 with the analog meter. I didnt stop there. If I move the ends around the resistance changes... so I hooked it to the DVM and moved it around and it changes on that one too, (flexing the ends some) so there must be something wrong with the resistor. Should I just go ahead and get a new 36 ohm resistor and replace it? Then I'd know it was right.
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  #26  
Old 12-06-2015, 06:04 PM
old_coot88 old_coot88 is offline
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Quote:
Originally Posted by fixmeplease View Post
I am lost about the cracking one in two idea.
That's only if the resistor is open and needs replacing, and you want to determine the original value. Obviously you don't want to cracka resistor that has continuity.
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  #27  
Old 12-06-2015, 06:10 PM
old_coot88 old_coot88 is offline
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Quote:
Originally Posted by zeno View Post
Great tip !! 40yrs in the biz & I never heard it.

73 Zeno
Don't feel bad bro. I had never heard of the 'aspirin trick' for stripping fine wire until recently.
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  #28  
Old 12-06-2015, 09:12 PM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by fixmeplease View Post
OK, I dug out my analog meter and hooked a 330 ohm resistor to it and calibrated it to that. When I put the resistor in question on it, its reading about 68 with the analog meter. I didnt stop there. If I move the ends around the resistance changes... so I hooked it to the DVM and moved it around and it changes on that one too, (flexing the ends some) so there must be something wrong with the resistor. Should I just go ahead and get a new 36 ohm resistor and replace it? Then I'd know it was right.
There might be a loose internal connection in the resistor, or poor contact with the meter leads.
For now, just jumper in the 'lytics and see what the set will do. If the tubes light up OK, proceed further.
BTW, the HV rectifier is the only tube that is not part of the series string. It receives it's filament voltage from the winding on the flyback on a properly working horizontal output stage.
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  #29  
Old 12-07-2015, 05:08 PM
fixmeplease fixmeplease is offline
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I will try the above after my tube replacements and parts arrive, and will post back. Thanks!
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  #30  
Old 12-11-2015, 08:58 AM
fixmeplease fixmeplease is offline
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My aqua dag coating is supposed to arrive today so Ive been outside scraping the old coating off, which went pretty good. Almost all of it has been removed but I have a question. in the picture I am including, I circled a small amount of dag which is closest to the neck. There is some other type of coating, which doesnt look like dag, above the part circled. Is there an electric connection between the two areas or are they isolated from each other somehow? EDIT: Now that the sun broke from the clouds I can see that its on the inside of the tube so I answered my own question and feel dumb, LOL
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Last edited by fixmeplease; 12-11-2015 at 11:10 AM.
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