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Help: New Casio Watch Battery, Lost 'Beep Alarm'

J

John Blake

Jan 1, 1970
0
Any ideas what might have gone wrong in
reassembling a Casio F-91W digital watch (or
similar) after a 3-V cell change that's
making the audio transducer inaudible? The
LCD lamp-button works, as do other setting
buttons.

The alarm works, dislaying a blinking LCD
symbol when it activates, but no beeping
sound. THe usual beep when changing modes is
also missing. I'd like to know what to look
for if I take it apart again.

Thanks for your tips.

John
 
D

Dave

Jan 1, 1970
0
John Blake said:
Any ideas what might have gone wrong in
reassembling a Casio F-91W digital watch (or
similar) after a 3-V cell change that's
making the audio transducer inaudible? The
LCD lamp-button works, as do other setting
buttons.

The alarm works, dislaying a blinking LCD
symbol when it activates, but no beeping
sound. THe usual beep when changing modes is
also missing. I'd like to know what to look
for if I take it apart again.

Thanks for your tips.

John

is the back on the correct war around? The transducer is part of a plate on
the back. If it is upside down, then no transducer.
 
R

rusking

Jan 1, 1970
0
You may have lost a tiny spring which contacts the transducer
if it's on the back plate as mine is.
Rus
 
J

Jerry G.

Jan 1, 1970
0
Either you have the rear plate on backwards, and or you lost the contact
spring. If you lost any parts, casio is easy to get in touch with and
purchase parts.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


Any ideas what might have gone wrong in
reassembling a Casio F-91W digital watch (or
similar) after a 3-V cell change that's
making the audio transducer inaudible? The
LCD lamp-button works, as do other setting
buttons.

The alarm works, dislaying a blinking LCD
symbol when it activates, but no beeping
sound. THe usual beep when changing modes is
also missing. I'd like to know what to look
for if I take it apart again.

Thanks for your tips.

John
 
S

Sam Goldwasser

Jan 1, 1970
0
Dave said:
is the back on the correct war around? The transducer is part of a plate on
the back. If it is upside down, then no transducer.

That's what is sounds like. Or, one of the little spring contacts is
bent of or has fallen out.

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Important: The email address in this message header may no longer work. To
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J

John Blake

Jan 1, 1970
0
John said:
Any ideas what might have gone wrong in reassembling a Casio F-91W
digital watch (or similar) after a 3-V cell change that's making the
audio transducer inaudible? The LCD lamp-button works, as do other
setting buttons.

The alarm works, dislaying a blinking LCD symbol when it activates, but
no beeping sound. THe usual beep when changing modes is also missing.
I'd like to know what to look for if I take it apart again.

Thanks for your tips.

John

Many thanks for the replies. Don't think I
left out a spring. But there was a bent-up
tab on the back plate (not the screw-on rear
case plate), located just above a tiny
metallic cylinder that I suspected might be
the transducer.

Initially I tried installing the back plate
180 degrees twisted until I saw the the
Casio's 3 push buttons didn't match the three
grooves on the watch 'chassis'.

Also, the original cell had a tiny piece of
black insulating tape on it (sticky both
sides), located just above the transducer. I
didn't put any replacement tape on the new
cell, thinking it might have been just to
hold the cell still during assembly. The back
of the watch chassis had a piece of white
tape on its back, and I substituted clear
Scotch tape when I reassembled it.
John
 
A

Alan 'A.J.' Franzman

Jan 1, 1970
0
John Blake said:
Many thanks for the replies. Don't think I
left out a spring.

These springs are usually quite tiny and can fly out as the back is removed,
in which case you might never have had a chance to see it!
But there was a bent-up
tab on the back plate (not the screw-on rear
case plate), located just above a tiny
metallic cylinder that I suspected might be
the transducer.

The metallic cylinder is probably the quartz crystal, the watch's main
timekeeping component. The "transducer" is usually a thin piezoelectric
element laminated directly to the inner side of the case back. There will
typically be a dull silver-colored conductive coating on the surface, which
shows marks readily. If the case back has been removed and replaced properly
a few times, there should be an obvious place where electrical contact was
made. Also, there must be a second connection to this piezo element through
the case back itself, which may be made near an edge away from the element, or
with metal-cased watches, via the case.
Initially I tried installing the back plate
180 degrees twisted until I saw the the
Casio's 3 push buttons didn't match the three
grooves on the watch 'chassis'.

Also, the original cell had a tiny piece of
black insulating tape on it (sticky both
sides), located just above the transducer. I
didn't put any replacement tape on the new
cell, thinking it might have been just to
hold the cell still during assembly. The back
of the watch chassis had a piece of white
tape on its back, and I substituted clear
Scotch tape when I reassembled it.
John

--
--------------------

Alan "A.J." Franzman

Email: a.j.franzman at verizon dot net

--------------------
 
C

Clifton T. Sharp Jr.

Jan 1, 1970
0
John said:
The alarm works, dislaying a blinking LCD
symbol when it activates, but no beeping
sound.

The last time I had that happen, the new battery was bad. It had just
enough power to run the clock and display, but when the buzzer tried to
sound, it drew enough power to disappear the display in blinking fashion.

In my experience it's not unusual to get a brand-new battery that's dead.
 
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