Electronics Forum / Electronics / May 2009

Is anyone else as horrified at Leo's latest outburst in his magazine as I
am? There is a rather surprising amount of ignorance displayed in his
editorial. He seems to have the same scientific outlook as George W Bush,
John Howard and Andrew Bolt. Which is to say, none at all.

I have a device which makes a "ping" noise on a piezo tweeter (one of those 10p sized things you get in wrist watches).  Is there any way I can connect this output to some LEDs to flash when it makes the noise?

<bitch alert>
Needed a replacement low-ESR cap for a repair job.  Nearest outlet is a Jaycar,
and I had the driver going past.  Checked their web page for the part dimensions
and all was tickety-poo, matching the dud.  Driver returns with the supplied

Hey Guys,
I have a couple of 4 month old 18V Ryobi cordless drill batteries that
were working fine with casual use in that they were charging and
discharging properly until one of them has decided not to charge up again.

I am attempting to understand the computation of various interesting
quantities (eg, insertion loss as a function of frequency) that come
out of an analysis of a lossless LC filter using the ABCD matrix.
Wikipedia gives me the terms for series and shunt R, series L, and

I am hoping to find someone with experience in programming with Splat's
FastTrack language. I would happily write the program myself but company
politics prevents it.
Nothing too outlandish required. Just reading and comparing a couple of

I've been working with microcontrollers for a while my thoughts have
led to maybe buying a 'scope'.
This has led to the great search on 2-channel scopes that will do
reasonable speed, and the question of what the minimal requirement

We have a problem with the a TRIAC device we are using.
We are using it to switch 230V AC mains on and Off.
The gate is connected directly to the output of our Attiny processor.
The whole cct is at mains level with + 5V generated from the mains for

OK, here's a question for all the old AWA techs on here!!
Looking for some info/schematics for a power supply 1LP82162, made for AWA
by Antaron Aust.  13.8VDC 8A supply, from old commercial 2-way site.
Also some info on the AWA "Automatic Battery Changeover Unit" 1LW82185.

see http://www.recalls.gov.au/content/index.phtml/itemId/964924
Fluke Australia Pty Ltd-Fluke 33X Clamp Meters
PRA number: 2009/10778
Date created: 4th May 2009

Hi Dave,
Keep up the good work.
Your EEEV blogs have become a regular feature and you are definitely
becoming a lot more relaxed in your presentation style which IMHO makes the

Yesterday, my Sharp/Fronius 1kW system was installed and today I saw the benefit
on the meter. At the end of the day the meter reading was about 2 kWh less than
at the start of the day. The peak power production was around 840W due to the
sun being at rather a low angle at this time ...

I'm looking for very cheap low current EHT supply at about 10KV DC.
These used to be easy to find, often from scrapped photocopiers or laser
printers.
Does anyone know a source, preferably in the UK?

Quick question :
Are Jaycar & Altronics the only 2 stores left in AU that sell kits of
Silicon Chip Magazine projects ?
I have noticed that DSE have nothing anymore but was wondering if there's

http://www.news.com.au/technology/story/0,25642,25515541-5014239,00.html
SCIENTISTS have unveiled new DVD technology that stores data in five
dimensions, making it possible to pack more than 2000 movies onto a
single disc.