View Full Version : What's going on with this B&W Emerson?


Mr.B&W
05-08-2015, 07:49 PM
Emerson 13 in black and white, model no. Bc126 possible linearity problems, bottom inch of picture is cut off, in the process of recapping electrolytics. Attached image. Thanks

zeno
05-09-2015, 08:38 AM
I dont have a manual listed how old is it ?

If its a tube set there is usually an electrolytic on
the vert out cathode that can cause lin problems,
common fail on many incl. color sets.

73 Zeno:smoke:

Boobtubeman
05-09-2015, 05:47 PM
The guy on the screen needs to lay off the drugs.... :D

SR

maxhifi
05-09-2015, 06:17 PM
Have you tried adjusting the vertical linearity and vertical size? Getting those two right can be a perfectionist's nightmare.

JB5pro
05-10-2015, 12:01 AM
I think that was dan akroyd's personal set. He described something like that which inspired the coneheads :banana:

radiotvnut
05-10-2015, 01:12 AM
The model number sounds like a solid state set from the '80's. The problem is almost certainly a bad electrolytic capacitor in the vertical circuit.

zeno
05-10-2015, 07:40 AM
If this started AFTER re-capping be sure all the caps
are the right value & put in the right way.
Assuming its a solid state set the vert would never
get so far out of adjustment, it would be a component
failure. Also be sure the V hold, V size & V lin controls
are OK they are cheap & easy to break.

HINT when re-capping do one or two at a time then
test for major changes. This will save a lot of grief !

73 Zeno:smoke:

Electronic M
05-10-2015, 12:45 PM
I think that was dan akroyd's personal set. He described something like that which inspired the coneheads :banana:

Eeeent! Wrong! The coneheads were part of a SNL Frank Zappa guest host episode (Zappa was there to pick up their daughter). The coneheads were a spoof of Zappa's song 'conehead' from his album 'You Are What You Is' (last song on side 2 of 4). Zappa was probably inspired by a TV with vertical issues though. He mocked TV many times in his music...'Trouble Every Day' is an early example, and ' I'm The Slime' is perhaps his most direct jab at TV.

colectorad
05-12-2015, 04:38 AM
Eeeent! Wrong! The coneheads were part of a SNL Frank Zappa guest host episode (Zappa was there to pick up their daughter). The coneheads were a spoof of Zappa's song 'conehead' from his album 'You Are What You Is' (last song on side 2 of 4).

Who fact-checked this game show? The first coneheads sketch is from '77, while 'You Are What You Is' came out in '81.

Mr.B&W
05-13-2015, 06:53 PM
hey guys, thank for all the helpful posts, well after I replaced the the electrolytics in the vertical circuit, IT HAD A PICTURE, but it still had a tendency to roll, which it didn't do before so I don't think the vert. hold pot is bad for now, but anyways I just figure ill go ahead and continue recapping, so I work my way through the horizontal and the Sif circuits, and test it again...DAMN now its just an even worse linear mess!, I'll attach an image of the symptoms later, I have several theories as to why this happened 1. I substituted two 33UF 50V caps for a 33UF 25V and 33 UF 16 volt in the Sif circuit, and in the horizontal circuit I substituted a .033 film cap for a .027 film cap, Could these voltage differences be causing this? 2. I'm thinking this has got to be in the vertical circuit somewhere but I've poured over it and cant find anything, every cap in that circuit was replaced exact UF and Voltage except for a 4.7 UF 50V for a 4.7 UF 16V, again possible voltage problem? or 3. there is a 2.2 UF 250V capacitor that sits in between the vertical and horizontal and unsoldered it to see its value but since I didn't have one I just soldered it back in, could that have caused that cap to leak or something? , I haven't been able to find a schematic so far so that the best I can do, I'm sure I probably made a rookie mistake in here somewhere, but I'm stumped, thanks guys

Electronic M
05-13-2015, 08:41 PM
Voltage rating of caps is a 'maximum safe voltage rating' in other words it is the voltage level that if the circuit exceeds causes the cap to go 'boom!'. Replacing with a higher voltage rated cap is acceptable, but replacing with a smaller voltage rated cap is not.

You want to keep capacitance as close as you can.

Mr.B&W
05-15-2015, 03:41 AM
well I found out what I did wrong, In my tired haze I misplaced a .047 mf cap for a 4.7mf in the vertical circuit, after I swapped them back she was good as new! Posting some pics of the after below, thanks VK! BTW, this is a solid state man. June 1986 forgot that info in earlier posts.@radiotvnut, yeah sure enough a bad 4.7 uf cap in the vertical was the culprit, although I recapped the whole thing. @ Zeno yeah I got a little ahead of myself replacing 5 caps at once (That's the 2008 Orange Bowl in the pic)