Electronics Forum / Electronics / February 2005

Can anyone recommend a good etchant to use for PCB's
I've tried FeCl and the HCL+H20+Hyd. Peroxide (1:2:1)
Both seem to take forever to etch my board (about 30 mins for a 10x10cm
board). After about 30 mins there is still a few areas not etched away, but

Hi all, firstly am not sure if this is the right newsgroup, if not -
please point to the one that is...
I would like to establish the exact way most laptop LCD displays work in
(if any specific info re. iBook is present - it will be most welcome).

Ploter is a Roland DXY 1200
I have a Circuit (in pdf) that  i want to plot to a board, but. i need to
mirror the image to be correct, The original pdf i have plots fine (except i
need it mirrored) The only way i can tell to mirror a pdf is exporting out

I have a swimming pool pump that I'd like to turn on if either one (or both)
of two conditions exist:
Presently the pump's power cord can be plugged into either a clock/timer so
it will turn on at certain times of the day that I choose,

Looky there, it's Toho, Tj, Tho, Assrat or whatever he's calling himself
today.

I picked up an old power  supply at the Wyong field
day last Sunday. It is made by Weston Electronics.
Model PS-20     The rear label says 13.8V    18 Amps max.
I am guessing that the unit is 30 years old,  maybe more.

I took a pen lazer, , applied a couple volts and an Audio signal, wired a
solar panel to an audio receiver , beam lazer onto solar panel and i get the
audio comming out of receiver,.
TIA

I am looking for a place to buy small quantities of misc electrical stuff
like potentiometers, good quality wire terminals, crimpers, wire etc.
preferably north of detroit near pontiac MI.
Please dont tell me to go to radio shack!

Hi, all
I am selling PCs and always I have to discuss wit customers their software
needs. Basically, they ask me to put software on their machines to do
particular tasks and I have to explain to them why software costs more than

Please somebody help. Camcorder Sony ccd-tr75e. Latest:
Has had all caps replaced, all is in working order except for the
viewfider image is strugling to appear. sometime I think it looks like
a negative but only just and other times I see dark shadows of the

Tesla didn't have an oscilloscope, so how did he figure out
frequencies?  
 I'm trying to make a tank circuit, but I don't have an oscilloscope.
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The European Space Agency Tech Transfer program is promoting a sensor
which stick  s on any hard surface and turns it into a
tap-keyboard/switch/control board:
http://glikglik.blogspot.com/2005/02/time-reversal-switch.html

Hi guys, I want to change the power/eject led's in my xbox. The
current led's are green/red bi-coloured and I want to change them for
blue/red bi-colour. I measured the voltage on the green led and it's
3.2v but the working voltage for the blue is 3.5v. although 3.2v does

Im a total newbie to PCB design, i have to build a high-speed PCB for a
board containing an Atmel At91 microcontroller operating at 200MHz,
with RAM, Flash, etc, so im trying to collect info on PCB design.
The question may be a bit misleading, heres the actual dope:

Hi, I can't for the life of me remember what the PNP equivalent of a BC547
is, nor of a 2N2222.
Does anyone know?
TIA