Sony TV-950 Saved from Goodwill Recycling

[dieseljeep]

Originally Posted by Captainclock

OK, I'll see about getting that Realistic monitor. I think its still there.
I'll check the Screen control Adjustment. The Sony Has the same issue I noticed, so I guess I'll check the screen control on it as well.

B/W sets don't have a screen control AFAIK. Maybe a brightness range. The CRT is probably just weak from heavy usage.

[Captainclock]

Originally Posted by dieseljeep

B/W sets don't have a screen control AFAIK. Maybe a brightness range. The CRT is probably just weak from heavy usage.

Hmm, well when I adjust the brightness and contrast controls the screen does some funky stuff like making light tones like light colored skin and what not look almost greyish-black instead of white colored (and dark colored skin and other darker tones look whiteish colored almost like its inverting the greytones), is that a sign that the picture tube is about shot?

[jr_tech]

Originally Posted by Captainclock

Hmm, well when I adjust the brightness and contrast controls the screen does some funky stuff like making light tones like light colored skin and what not look almost greyish-black instead of white colored (and dark colored skin and other darker tones look whiteish colored almost like its inverting the greytones), is that a sign that the picture tube is about shot?

Yes... CRT engineers refer to that phenomenon as "double peaking"... the beam current does not increase in a linear fashion as grid drive is increased, but may actually decrease and then increase again as grid drive is advanced farther, creating a second brightness peak. Very common on a worn out CRT.

jr

[Captainclock]

Originally Posted by jr_tech

Yes... CRT engineers refer to that phenomenon as "double peaking"... the beam current does not increase in a linear fashion as grid drive is increased, but may actually decrease and then increase again as grid drive is advanced farther, creating a second brightness peak. Very common on a worn out CRT.

jr

Ah, well that's too bad, well I guess it would make a nice displaye piece if nothing else.

As for my Montgomery Wards TV the Brightness has to be turned all the way up in order to see the picture otherwise you can't see anything, I was told that it might be an adjustment on the Flyback that needs to be adjusted (screen control?) but other than that I'm hoping that the picture tube isn't about dead on it because that would be rather odd for a TV that saw little use to have a failing picture tube already, especially when the color is fine yet just the brightness is a little off for some reason on it.

[centralradio]

Great save.

I think I have a set similar like this set.

I agree.Those PITA Sony power cords.Panasonic follows,are a nightmare If you dont get the right pinout and voltage info .

Pop goes the weasel.

[zeno]

CRT's almost always fail due to low emission. On a
B&W symptoms are dark pix, negative pix, streaking of
bright areas, slow warm up & overly bright whites with no detail or any
combination of.....

Best test is darken the room, turn down the bright & contrast.
If it looks a lot better its the CRT 99%.

All fixes are risky ( except a new CRT )
Rejuvenation, only use a MODERN CRT checker for this made
after the early 70's.
Brighteners only work on some sets.
Most sets have a low ohm resistor in series with the filament.
It can be jumped out to give a little more E but again risky.

As far as waking it up goes regular use will usually improve things
but its a process that goes on just like people getting old &
slowing down......

73 Zeno

[Captainclock]

Originally Posted by zeno

CRT's almost always fail due to low emission. On a
B&W symptoms are dark pix, negative pix, streaking of
bright areas, slow warm up & overly bright whites with no detail or any
combination of.....

Best test is darken the room, turn down the bright & contrast.
If it looks a lot better its the CRT 99%.

All fixes are risky ( except a new CRT )
Rejuvenation, only use a MODERN CRT checker for this made
after the early 70's.
Brighteners only work on some sets.
Most sets have a low ohm resistor in series with the filament.
It can be jumped out to give a little more E but again risky.

As far as waking it up goes regular use will usually improve things
but its a process that goes on just like people getting old &
slowing down......

73 Zeno

OK, I'll give the TV a try and see if it actually exibits any of the symptoms you mentioned or if perhaps its just needs time to wake up the CRT from not being used for a long time, seeing as this TV is from between 1967-1972 I would guess that this TV probably was supplanted by a modern Color TV and was just left in a guest bedroom for years unused, before the previous owners donated the TV to Goodwill.