Grundig Satellit 300

[Sylvia Else]

After operating OK since the repairs I did after dropping a curtain pole
on this radio a month or so back, the LCD is playing up.

If I perform an operation that clears the display, and enter an 8 digit,
it looks normal enough. If I enter a second 8 digit, some of the
segments of both digits (the same ones in each case) become fainter. If
I enter a third 8 digit, the segments become fainter still, and so on,
until they're pretty much invisible.

This suggests an issue with one (or more) of the backplanes.

The signals going in look normal enough, and in particular the backplane
signals don't change as I enter additional digits.

Any thoughts before it ends up on the tip?

Sylvia.

 

[N_Cook]

After operating OK since the repairs I did after dropping a curtain pole
on this radio a month or so back, the LCD is playing up.

If I perform an operation that clears the display, and enter an 8 digit,
it looks normal enough. If I enter a second 8 digit, some of the
segments of both digits (the same ones in each case) become fainter. If
I enter a third 8 digit, the segments become fainter still, and so on,
until they're pretty much invisible.

This suggests an issue with one (or more) of the backplanes.

The signals going in look normal enough, and in particular the backplane
signals don't change as I enter additional digits.

Any thoughts before it ends up on the tip?

Sylvia.

Is there a contrast control that got broken as well?
What other LCD legends etc other than the main 8 digit display ?

 

[Sylvia Else]

Is there a contrast control that got broken as well?
What other LCD legends etc other than the main 8 digit display ?

Can't see anything that adjusts contrast.

The LCD doesn't have that much other than digits, but those that it has
seem to work normally.

The digits appear thus


XXXXXX
X X
X X
X X
......
.. .
.. .
.. .
XXXXXX

Where XXX denotes segments that work, and ... denotes segments that don't.

All the digits are failing in the same way, including a small digit that
denotes a channel number.

Since my original posting, I surmised, by cutting tracks, that these
segments share a segment common, as do the top three. So then I
connected them the other way around, with the result that the digits
come out wrong or garbled, but the same three segments misbehaved.

The connection to the LCD is via an eltroconductive rubber strip, which
seems OK. Seems to me that the LCD itself is failing. Seems a strange
failure mode though.

Sylvia.

 

[N_Cook]

Can't see anything that adjusts contrast.

The LCD doesn't have that much other than digits, but those that it has
seem to work normally.

The digits appear thus


XXXXXX
X X
X X
X X
......
. .
. .
. .
XXXXXX

Where XXX denotes segments that work, and ... denotes segments that don't.

All the digits are failing in the same way, including a small digit that
denotes a channel number.

Since my original posting, I surmised, by cutting tracks, that these
segments share a segment common, as do the top three. So then I
connected them the other way around, with the result that the digits
come out wrong or garbled, but the same three segments misbehaved.

The connection to the LCD is via an eltroconductive rubber strip, which
seems OK. Seems to me that the LCD itself is failing. Seems a strange
failure mode though.

Sylvia.

So probably a crack in the glass at the backplane connections and so some
silver loaded paint
perhaps, if lucky and an exposed area.

 

[Sylvia Else]

So probably a crack in the glass at the backplane connections

Not entirely inconsistent with dropping a curtain rail on it, I suppose

and so some
silver loaded paint
perhaps, if lucky and an exposed area.

I can't see any defects.

Sylvia.

 

[Yaputya Leftlegin]

After operating OK since the repairs I did after dropping a curtain pole on this radio a month or so back, the LCD is playing up.

If I perform an operation that clears the display, and enter an 8 digit, it looks normal enough. If I enter a second 8 digit, some
of the segments of both digits (the same ones in each case) become fainter. If I enter a third 8 digit, the segments become
fainter still, and so on, until they're pretty much invisible.

This suggests an issue with one (or more) of the backplanes.

The signals going in look normal enough, and in particular the backplane signals don't change as I enter additional digits.

Any thoughts before it ends up on the tip?

Sylvia.

I have always found faulty LCDs to be unrepairable. They are too flimsy
in construction, high impedance tracks etc,
If its got a clock function, you might salvage a 32kHz crystal.
Otherwise the tip.