Electronics Forum / Electronics / April 2005

Just restoring an old Dexxa Flatbed scanner (4800) and I'm wondering if
someone knows what type of tape/adhesive would work best on the glass?  The
original stuff holding the glass to the case seemed to be very, very thin
double sided tape, but it has lost some power and so the ...

I am requesting help to construct an ultrasonic device that emits sound at
about 25Khz.  Unlike most ultrasonic devices, I want the device to carry
sound over 100 feet (or 30 meters) and still be over 140 decibels at 100
feet (or 30 meters).

Underlying the key mechanisms is a double-sided film with concentric circuit
pads (for each key) on either side of the film. The key cap pushes down a
little inverted cone of what looks like silicone rubber to touch the film.
This isn't a contact switch; the top of the film has ...

WOW!  750kV AC!  -+500kV DC!  The 2nd & 3ed pages give pics and info on
the generators, etc.  Each of the 18 generators puts out over 700MW,
which is about as much as half a regular or nuclear generating station!
Mamma mia!  Two separate power plants.  Rectifiers the size of

You can build a cheap 8-bit 255 speed DC motor speed controller
from the parallel port of a PC.
    PC Parallel Port Pinouts
(i) denotes an input signal to the computer.

I am requesting help to construct an ultrasonic device that emits sound at
about 25Khz.  Unlike most ultrasonic devices, I want the device to carry
sound over 100 feet (or 30 meters) and still be over 140 decibels at 100
feet (or 30 meters).

I'm getting a TV with both S-Video and Component inputs.  My
DVD player also has S-Video and Component outputs and I'm
wondering which way I should go?  I've read that it's hard
to tell the difference so on what basis does one make the

hi, any body  have or know of a schematic for a 10  amp lead acid  charger
for car batteries ?
something sorta basic , which  keeps it on trickle charge, after its fully
charged ..

Hi!!
Is there anyone who has used PIC16f877 microcontroller for
transmission and recieving of data. I am working on a small project
where I need to do wireless tranmission of data using PIC16f877 along

For my sony television i am looking for this part ERD08M15 (a Fuji Diode).
And i cannot find it in a quantity of 1 or 2 peace(s). Please can anyone
give me an address to order this, or can you offer me this Diode please let
me know.....

Goodaye to all,
I am after a service manual or schematic for an AWA CTV Model - 5190S,
can anyone help.
I have tried HCSD, but they don't have any manuals for this model.

As far as i know, there is no need for many (6 before and 6 after
field synch)equalizing pulses in RS170 video anymore. Does any of you
know sources (preferable official) supporting this claim?
Regards,

My new TV has a 3 line digital comb filter.  I understand that it's supposed
to improve the image, but what does it do technically speaking?  Does it
make a significant difference?

Hi,
Does anybody know if I use a 5V, 0.8A adaptor plugged into my car's
cigarette lighter to charge my MP3 player (that is supposed to be
charged with a 5V, 1.6A charger), will it do any damage, to either the

Another good one last night. They did ship-sinking experiments,
and several versions of an exploding trombone.
SBS television in Australia is now referring to Mythbusters
as their "cult phonomenon."