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#16
07-07-2012, 10:47 AM
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The ring mount in my pic is original i believe, I didnt make it. A simple ring clip that has 2 mounting brackets attached to both exteneded parts of the front chassis. It holds the CRT in place and enables me to flip the tv around when servicing
 Steve 
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#20
08-02-2012, 03:02 AM
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I have an 8T-243 set in good condition that I would like to move. I was going to restore it, but I have too many other irons in the fire and to be small sets these things are really heavy! Like other sets that old, I did have to work on the power supply in order to save a few 5U4 rectifiers from flaming out. Surprisingly, the set came closer to working than I would have ever suspected for a set that was likely dormant since the 60s (I would imagine). Of course it still will need a recap, but all of the essentials have been verified as good. Email me at [email protected] if interested.
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#21
12-18-2012, 10:03 AM
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Hi All;
I have a 8T244, which is like yours.. On the other site, I have been told not to plug mine in any more until I Re-cap it.. I had run it for hours at a time about 3 to 5 years ago when I last had it on the table to work on.. I would be interested in what you did to Re-forn your caps.. I can't say it will help my set, but I can look at what you say and then decide.. I also had problems with it arching around my Flyback, and even after doping and such it sttill would arc a little.. So, I finially just put an old Bicycle inner tube along the top around to the bottom of the flyback, and no more arching.. I know that some would scoff at that, but it works..  THANK YOU Marty
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#22
12-18-2012, 10:21 AM
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after replacing all the wax paper caps, I disconnected the can caps from the circuit (did not remove them from the chassis, just disconnected the terminals), and then used a vintage eye tube type cap tester. I started out on the lowest voltage leak test (25v IIRC) and would fix the test knob so the voltage would stay applied for an extended period. Most of the sections tested shorted (eye would not open), but over time the eye would open, when it did I would switch to the next higher voltage and repeat the process until the eye would fully open at the rated voltage.
I do not think the process would have worked as well if I had just used a variac for a lot of reasons that I don't want to take the time to document. Variacs are useful tools but not for reforming. Note, I am not saying this technique will always work or if it works how long the caps may last. In fact if I was repairing the set for someone I would not even bother, rather I would prob just put in new caps, it would be faster and prob safer, but I like to experiment and that was what this one was about. Lastly I always put a fuse on the B+, and size it so it will blow quickly. If SS rectifier is used I will add a thermistor to allow for a fuse that is also just above the max operating current (inrush will blow a fuse too close to max). Fusing should be done regardless of what is done about caps (reform or new), frankly new caps can fail, and in some cases I think a good old can cap may outlast some BS china cap.
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#23
12-18-2012, 10:48 AM
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Hi All;
Dave can you tell me which Cap tester you have ?? I have a Solar Exam-eter Model CF.. I don't even know IF it works.. And I need to get the manual for it, I found the site the other day, but had ran out of printer paper, from before, so I did not print it.. THANK YOU Marty
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#24
12-18-2012, 11:02 AM
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Heath kit. Pretty much any old school cap tester should work, just need something that has a leak test that goes up high enough (think mine is 450v tops). Some testers use an eye tube, others a meter, the meter is prob better, I ofter will put a current meter in series with the cap to see exactly how much leakage there is (even with a fully open eye they will leak some). comparing to a new cap gives you an idea of how good an old one is. I recall there is a table somewhere that shows the allowable leakage in mA by capacity.
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#26
12-18-2012, 12:40 PM
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Quote:
I have cleaned out the HV cage every decade or so. Are you seeing actual arcing or is it a corona discharge (eg hissing)? Problems or corona are generally due to contamination (dirt) or sharp points. Making sure everything is clean and connections are well rounded eliminate the problem.
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#27
12-18-2012, 03:02 PM
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Hi All;
I have not powered it up, since I was told not to, so I can't say, that If I remove the inner tube, that the arching or hissing would return.. The last time I really worked on it was about 3 to 4 years ago.. I don't remember why I stopped.. I do know that, there was a problem, with when a cap was hooked up, the signal would disappear from the screen, (I can't remember If I lost Raster).. After reading many of the posting recently, I have two possible conclustions, one is the cap is bad or very leaky or shorted.. or, it is connected to the wrong point on one end.. I know it is in the right area, but the Sams photos are not clear enough for me to know for sure.. Eventually, I will need to check every connection in the area and make sure all is correct.. Also, since it has been that long since I worked on it, that I might have already removed the offending cap, and it is no longer there.. Also, another problem to throw into the mix, is When I first got the set, I had no picture at all.. I later put in a 5BP4 (I think number is correct) from my other B&K 1077, and got a picture, so I knew that the HV section worked after all.. But, every and I mean Every knob and control and anything that could be adjusted had been fiddled with trying to get a picture on the 10BP4.. I a little later got for Free an origional 10BP4, with a date of 9-49 on it.. (Calvideo).. I got some raster on it.. But, since I tried it about a week ago, it showed nothing, But, I didn't fidle with any controls, and put in the 5BP4, fiddled with the controls a little and got a partial picture.. Since then I have NOT turned on the Set.. But, watching all of the other early restorations, just makes me want to get this set going, at least somewhat.. But, until I can save up enough for the Electrolytics (about $70.00) and that doesn't include all the wax caps, etc.. So, this is the state of where the set is at present.. So, possibly I could remove the inner tube and it would be fine.. Just don't know for now.. THANK YOU Marty Last edited by Geist; 12-18-2012 at 03:06 PM.
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#30
12-18-2012, 03:17 PM
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The electrolytics on these sets are very good quality. I have had four late forties RCA sets and have reformed them all. One went bad: it opened up. I have never had a shorted electrolytic on these sets.
I would encourage you to test and reform them. I is very straightforward and you can easily determine if you are successful or not.
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