Electronics Forum / Electronics / October 2004

I realize that discarded electronics found on the street can be useful,
if only for parts. However, I was told recently that there seems to
be a resurgence of bedbugs in the US and that one of the places they
can turn up is in discarded stuff found on the street. So, I'm wondering

I went to the veroboard website
http://www.verotl.com/products/index.cfm?content_id=2424A965-4AF2-433B-9
589A039D35545F5
and found a choice of verious sized boards to choos from.  I also went

I heard or spotted somewhere that putting batteries in the freezer prolongs
there life until needed, is this a myth or what?

if I have to use diodes , which type of  industrial dioxdes for hydro power
generator thatI should apply ?
http://www.web7days.com/hydro/tn/PICT0004.JPG.html
power source( 12V- 36V)  from generators to the battery.

Picture on this TV has collapsed to a thin line (white) in the centre,
across the width of screen.
I have no diagram!
Any clues please?

hi, is there any way to increase the out put  voltage from a 7812  voltage
regulator ?
i need to increase it to about 13.8 volts .
thanks, mark k

I after older microprocessor development type boards and BOOKS ..pre
1980's and on ..mainly all the early microprocessors,
8080,8085,z80,6502,6800,SC/MP 2650 etc and all the early 16 bit ones
8086,TMS9900,68000 ,z8000 etc ..

http://www.geocities.com/tbsheth
FREE HELP FOR EXAM & QUIZ
I welcome all electronics engineering.
I want to give a large callection of engineering question. on my site

I have a 50 watt valve amp which seems to have blown its
output transformer. A new one is on order, but I was puzzled
by some of the reading I got off it and wondered if someone
could give an explanation. All the measurements were made

I have a pair of speakers that need a 13V and 2A DC power adapter or wall
wart. I lost its wall wart and found a wall wart for another device, which I
have no idea what its for.. it gives out 15V and 400mA DC.
The power adapter I found said on its back that it must not be used with ...

Anyone know where I can find a few UDN7180A IC chips? I have contacted a few
places on the net and either they don't sell them anymore or I don't get any
resonse.
Thanks,

I am looking for the equivalent in PAL for a device I am making so it can
display black and white images on PAL screens. The RS170 standard is one
line every 63.625 uS with 3 voltage levels (black, white, sync). There are
262 lines every 1/60 of a second, interlaced.

[sorry for the cross posting]
Is there any *cheap* way to remove scratches from scratched CD's (both audio and
data disks)?
Thanks.

I would like to build a *very simple* "sleep timer" circuit to incorporate
into a stereo system.  It should switch the mains, and could even be in a
separate small box.  The idea is to press a button to give me power for one
hour only.

hello,
i have an appliance imported from the US, a small piece of computer
audio hardware. it uses a fully external 'wall wart' power supply and i
was told by the company that i will be able to use it fine locally with