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#16
05-18-2011, 10:18 PM
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pluging into the full power (no variac dropping the voltage) resulted in a nice full rastor.
I either get No color or color bars rolling thru (no sync). It has a very soft horz lock, you can flop it both ways with the horz control so I presume the osc is working and when carefully adj it will hold but the phase is not solid (scene floats across the screen), so I presume there is a prob in the AFC on the horz, prob diodes or drifted resistors in the horz afc. I will just go a head and replace them rather than fooling around with it. My guess is the lack of solid horz lock is messing up the burst amp keying pulse from the flyback, and maybe a weak 3.58mhz crystal on top of that. I do get momentary color lock but its very fleeting. I have checked the tubes in the video/chroma, replaced one very weak 6GH8 (osc) and found a tube shield for it (was missing and not loose, darn tech...) and replace a 6WE6 that had a short that would show up after it heated up. Tested the radio, all seemed good but for normal dirty speaker switches, but I will do a full recap of that later. I know there are a bunch of 5uf lytics in it that tend to dry up. I also will do the stereo mod to the TV selector so I can use the amp and drive it with the audio out from the DVD (will make an adapter that will allow reverting back the the interal TV audio buy just pluging it back in, did this before on the B&W maggie). 
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#17
05-18-2011, 11:05 PM
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Don't mess with the crystal till you replace any suspect caps in that circuit- and they are all suspect believe you me. Sounds like the horizontal section needs caps too, I find that even with drifted resistors a stable lock should be obtainable.
__________________
Evolution... 
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#18
05-18-2011, 11:14 PM
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So it did turn out to have more problems than initially thought. Get the horz lock thing fixed then I bet the color may lock in. You can always tweak on the color osc coil a tad and see if it pops in.
The good thing is nothing major just little annoying stuff. I have a feeling those diodes are selenium and expire form time.
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#19
05-19-2011, 12:35 AM
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I am impressed that you were able to find a color set in florida! Back when I lived there (same time I started collecting TVs) I only ever saw 3 monochrome TVs (I snaped up two, but one got away cause my car could not fit two consoles). Even in the radio belt it aint the easiest thing to find a roundy. If I were you I would have bought a lottery ticket the same day as that set, and prayed not to get struck by lightining.
Tom C.
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#21
05-19-2011, 06:59 PM
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tried subbing a sync sep tube (6gh8) no real improvement, so I decided to pull the chassis. 1st order of bus is to pull the speaker under the tuner/control cluster, then pull the cluster (after the confusing way its mounted using the pot shafts as mount screws. Of course all the strain reliefs were broken, no big, and of course the prior tech did not bother to replace the tuner cover (was this common practice?) perhaps due to the difficulting in removeing the tuner it was decided it just did not need a cover....
moving on to the chassis, one screw that was just barely in just a couple of turns and the chassis was loose (thanks again mister tech). I finally get the chassis out, nice, a alligator clip wire is soldered to the center post of the video amp and burst amp tube sockets, and then the clip is on the chassis, sweet... My guess is there was a bad ground connection maybe even a broken pcb and this was the fix. He should have at least soldered the dumb thing oh and the wire was not covered all the way with insulation, looks like a splice was done and not covered, no evidence of any electrical tape or anything. lord what a hack. This tube socket on the bottom looks a bit funky, not sure if there was a replacement done and poor solder job or what. May account for the impromtu ground. other than that it looks pretty original. I will see if I can clean up the sockets, reflow some solder and may as well do a better job of what ever that ground wire was all about, not to mention reflowing the solder stakes. I have some strain reliefs so will button that up. I could not find the mounting point anywhere on the chassis for the tuner cluster.
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#24
05-19-2011, 08:11 PM
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oh I see he did attempt to solder somthing maybe even the ground stake, from the bottom, I can tell by the melted insulation of two small wires, enough so that the wire was showing thru, maybe even shorting (prob not but real real close). I will cut, splice and cover with some heat shrink.
what a HACK... The big degausser varistor is melted and nasty looking, I have a spare. The darn tuner center lead broke, I think I got it back on the right spot (it was not a plug in type) this happned before I fixed the strain relief, prob when I was messing with it trying to mount the cluster to the chassis. I am getting tired, and I am out of strain reliefs (need 2 more, top rack of pots and the main batch of leads coming out of the back of the chassis). I will prob just pull the AFC diodes and call it a night.
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#25
05-19-2011, 09:22 PM
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Quote:
Quote:
__________________
Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did."
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#26
05-20-2011, 12:13 AM
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ok AFC diode was leaky on one side, so that should fix the horz and hopefully the color sync.
was checking over the PS caps, the doubler was def a replacement, the give away was the masking tape cover, and the fact that it was a 2 section cap tied together (I doubt the factory would do that). I was extruding a nice rubber poop out of one of the unused slots on the bottom, looks like a heat and pressure issue, so I will be looking for a 160uf 250v AND a proper can cover. Its a bit crowded on the bottom so I will need to stuff a can. There are a few suspect caps that will get changed out, and it still has a bumblebee .047 safety cap (I will clip the leads long and dump in on the audiophools on ebay, should get enough to buy all the caps I will need).
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#27
05-20-2011, 12:21 AM
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thats all for tonite, I checked the .001 2kv elmenco on the primary of the vert out, value right on, no fuzzyness, no leakage at 450v (which is high as I can go). I would have replaced it anyway, but I only have some dipped that go to 1.6kv, so I will have to order some of those (I dont trust them).
there was a single black plastic .01 400v sprauge in the horz osc section, it tested perfect, no leakage at 450v so I left it alone. I am trying to not make too many changes just in case I goof something up, it was working after all but for the horz AFC. I did check the vert osc bypass cap a 50uf 150v, tested perfect again I left it. I randomly check a few of the purple dipped caps a .47 and a .1 both 200v, they checked fine, no fuzz no leak so maybe I will get lucky on this set and dipped caps. that bumblebee across the line was fuzzy and very leaky, I am suprised it had not blown up yet. I did have one open cap, a 100uf nichicon 25v that I think is part of a degaussing circuit. I see a diode and a relay all tied into that blown large VDR that is around the degaussing circuit.
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#30
05-20-2011, 12:18 PM
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popped for a full set of electros, about 35$ got that 2k vert out cap, and a new line suppression cap. This weekend it will be just the strain reliefs and the AFC, now that I have the caps on the way I will have to wait as I dont want to have to reinstall just to check it out. I really need to get my test jig installed in the shop.
I got all the caps from mouser, all radials, will stuff cut off the cans and leave the base in place, use a bone saw to do the cutting. I will prob check 1st, if the 450v's test ok I may just leave them.
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