crt TV OSD channel

[frank]

Hi all,
wierd thing of the day: the channel number (OSD overlay) on an old
14" CRT TV is never disappearing. I've never encountered this behaviour,
so I'm a bit unsure where to start diagnosing.
The chassis is a Nokia Mono Plus, few ICs do everything.
On the other hand, the volume OSD bar disappears quickly after the last
volume button action.
Any hint?
Frank

 

[Terry Schwartz]

On Sunday, December 24, 2017 at 5:41:05 AM UTC-6, frank wrote:

Hi all,
wierd thing of the day: the channel number (OSD overlay) on an old
14" CRT TV is never disappearing. I've never encountered this behaviour,
so I'm a bit unsure where to start diagnosing.
The chassis is a Nokia Mono Plus, few ICs do everything.
On the other hand, the volume OSD bar disappears quickly after the last
volume button action.
Any hint?
Frank

It may be a setting. Check the settings in the menus.

 

[frank]

Terry Schwartz <tschw10117@aol.com> wrote:

It may be a setting. Check the settings in the menus.

Menus in a 1980's TV? This is probably the first attempt at any kind of OSD.

Frank

 

[Terry Schwartz]

It may be a setting. Check the settings in the menus.

Menus in a 1980's TV? This is probably the first attempt at any kind of OSD.

Frank

I had a Toshiba of similar vintage, maybe just slightly newer, and it had menus.

Heathkit and some Zenith TV's from even earlier has some OSDs. Caller ID and station number.

 

[Michael A Terrell]

frank wrote:

Terry Schwartz <tschw10117@aol.com> wrote:

It may be a setting. Check the settings in the menus.

Menus in a 1980's TV? This is probably the first attempt at any kind of OSD.

Frank

Do you have a schematic, or a datasheet on that IC? I've had shorted
ceramic capacitors on the control lines which kept a function locked. In
another case the bad capacitor shorted the input voltage that controlled
the brightness.

 

[Tim R]

I've had that happen on a CRT not quite that old.

It's really annoying. There was always some combination of inputs from the remote that fixed it, but sometimes it took us a couple weeks to hit on it again.