Using a Common mode Choke (differential) as a joule thief transformer (working)

Almost any switch mode power supply has one of these chokes for noise suppression.  The type pictured below is the type that has been tested working.

The prewound choke Coil has even windings on both sides and uses many turns of thick wire around a ferrite core.
Using the standard Joule Thief configuration, it has been tested with a BD139 transistor, 1.4K Ohm Feedback Resistor and a Blue LED.
Starts up easily at 0.6V DC. and is much brighter than the standard joule thief at 1.5 Volts.

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Click Nightguard Brand CLKRT200 Motion Torch Not charging

A great product, inductive coupled charged torch with nighttime motion detector.  Purchased from Bunnings 6 months ago for $20, stopped charging.  The base has a burnt smell coming from it.

Opened the base and found that the 224 / 400V polyester capacitor had ruptured and a resistor was burned beyond recognition.  Fuse was O.K.

It was very hard to  find a product website for the Click Brand.  A search on IP Australia disclosed that the trademark owner is Bunnings...

Alot of other are having similar issues with the CLKRT200 and CLKRT100.  Fuses blowing....  Poor design....
Lucky this did not catch on fire.

There is no real fix for this crap except to disable the inductive part altogether and power the thing of a external 5V AC or DC plugpack modded with a plugin connector.


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Create a Instant Microphone Audio Record Script using arecord and amixer

Why:  Sometimes you need to record something NOW.  Not Click menus and press record realizing that the microphone volume is too low.

Uses amixer, arecord and xterm all which are native applications with most Linux distros.  The script can be shortcutted to a button on the panel and give instant feedback that it is working with VU meters.  The record file is date-timestamped for easy reference.

The script is below and is commented for a bit more info on its working.


#!/bin/bash
amixer sset -c 0 'Mic' playback off
amixer sset -c 0 'Mic' 90%
amixer sset -c 0 'Mic Boost' 90%
amixer sset 'Capture' cap
amixer sset -c 0 'Capture' 90%
xterm -e arecord ~/record_$(date +%Y%m%d%H%M%S).wav -v -V'stereo' -f cd &


When you are done, just kill the script using Control+C and look in your home directory to find the datestamped wav file.  I found the arecord operating sends the microphone boost to 100% upon execution, but so does audacity.  This is not an issue for me but you may choose to use a lower 'Capture' level to even things out.

To migrate this script to a button on the panel, chmod +x the script file, then add the following command as a Custom Application Launcher

sh /path/to/script.sh


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New ebay.com.au fees and how to fight it

As you may be aware, ebay has increased its fees to four-finger the small time sellers out of the playground.

10% per item selling price and generally a extra 2.4% of the total price for paypal.  Further to this, the buy-it-now price must be over 30% of the initial bidding price, used to be allot lower.

Many have said they are moving to Gumtree, but Gumtree is owned by ebay and they are starting to exploit it's clients by charging just to edit a listing, what next...  I don't see the point of charging to edit a listing, it has no logic except to ween the user-base onto a fee structure.

Quicksales have announced, zero insertion and final value fees, but nothing sells there yet.  As with any corporations, as soon as it becomes popular, it's time to cash in on the party, so fees could be back around the corner.


To get back at ebay, you can protest by not selling anything there at all.  Here is a better way: 
The goal is to utilize you built up seller reputation and to make ebay appear to be a very expensive place to shop and if you are selling niche items, you definitely have an advantage of making some extra money.

• Continue to list items on ebay, but jack the price up more than 20% and don't forget the postage, increase it as well :)

• Utilize their buy-it-now (free) listing functions and make sure that the price is over 30% of your new total.

• Utilize the scheduler (free) to schedule you new listings to list of the most convenient times without having to be in front of the computer, generally 10 days ahead of time.

Sit back and watch the occasional sucker emptying their wallet for you.  It is surprising how some people like to waste their money.  Generally due to time constraints, lack of concentration, stupidness or just luck on your side.




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Electrolux E3 Error Fix for Free!

Electrolux Vacuums are now such a piece of crap.  Who the hell designs these things, their idiots.  Not like the old Electrolux days, the days that made the brand a popular and reliable choice.

The problem with this vacuum, it that it starts up for a few seconds, then the machine stops with a stupid E3 LED Flashing message.

The solution, bypass all the electronics and directly connect the power to the vacuum motor.  It is very simple and requires no alteration to the existing wiring.

Disassemble the vacuum.
At the back of the vacuum cleaner is a speed control board, find that.
Then look for two connectors, one with Blue/White wires (power) and one with both black wires (motor).
Separate both connectors and connect the male motor connector to the female power connector.  This bypasses the speed controller board altogether.
Put the whole thing back together.
No when you plug in the power, the vacuum comes on at full speed with no more crappy issues.  Electrolux products are a piece of crap.

To disassemble this thing, Alex from vacuumspot.com.au has a great video on dissembling the Electrolux vacuum below.  Buying a replacement board seems pointless as it is likely to happen again.

Brush Driver Board (Blown Fuse)

Speed Controller

Speed Controller, Stupid Air Cooling Cover Removed

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