Electronics Forum / Electronics / June 2004

I have just started to make my own PCBs. I read that the dust produced
when drilling the holes can be hazardous. Does anyone know why, do the
boards contain asbestos or something?
Thanks

Has anybody got a clue on how I might get or even perform a search for a high voltage power fet (>250v), preferably n-channel, that
doesn't have an internal zener? It must also have a low on-resistance.
I'm attempting to change the damping of a large back emf on the fly and the ...

Having trouble even identifying what a 74105 is.  Logic families have obviously
moved on since this one was around, and trusty Google  can't find any useful
info.
Can anyone tell me what it was, and possibly point me at a data sheet?

I have a circuit that needs 5v DC.  I put in a simple voltage divider to
take the 9v from a battery down to the required 5v.  The obvious problem is
that this only works while the battery is at or close to full charge.
I'm looking to learn how to provide 5v to the circuit ...

Please could some very kind person out there help me with this
revision question.
Q)What problems can be encountered when using switches as inputs to a
microcomputer and how can these problems be overcome.

I recently purchased a 20x4 backlit LCD from a surplus shop. It seems
to be in good working order, however, I am having difficulty getting
the last character in the 3rd and 4th lines to display properly.
The controller is a legit HD44780A00, and there are four HD44100H ICs

I am looking for a cabinet to terminate my home network and video
distribtuion into.
Can someone provide links to people in Australia (Melb preferred) that sell
cabinets to do this?

Has anyone played around with the USB V2.0 Flash Memory Drives?
I know the V1.1's are as slow as anything to write to, but I am
wondering if V2.0's do a better job.
I know it's the flash write cycle that takes up the real time, and I

Is there a commerical BJT part for modeling multi-collector and/or
multi-emitter BJTs in spice? Or could I model them just by using two
individual BJTs?
thanks!

For our production we are looking for a uProcessor from NEC.
uPD78F0103M2MC-5A4
Lead time from NEC is at the moment 20 weeks.
But we need it faster.

I have one of these printers that refuses to feed paper into the printer and
then comes up with an out of paper error. Is this a common problem and is
there a simple fix.
Many Thanks

Can anyone point me to any websit or provide information about
how to listen to a conversation through a concrete wall?
Thanks

We had a thunderstorm and the power blinked on and
off.  Then the TV wouldn't work.
The power switch relay clicks and clicks again after a
few seconds, but no sound or picture. It won't click twice again unless you

I have an application where I have 2 supply sources vary in range of 300mV-800mV.
I need a circuit that can take these 2 signals and output the average voltage of both. Can it be done fairly simply?
thanks
Tim

DVD's played through my television make a loud and regular popping sound.
The components are:
Philips Magnavox Smart Series Televsion, 1998
CyberHome Mini DVD Player CH-DVD 320, 2003