CRAP the most important file on my system!

I often need to temporary create a file or folder when I am working on my computer. Often I forget to delete this work when I have finished using it. Last Century I devised a method to eliminate this clutter. It has saved me having to review thousands of useless files. This file or folder is named CRAP, crap.jpg, crap.txt, crap.js, crap.whatever. I allow uppercase or lowercase. I allow longer crap names like crap1 or crap.spreadsheet. From time to time I search my system for files matching crap*.* and delete them as per the rules below.

Crap Rules

Rule 1: When you see a crap file or folder NEVER OPEN IT.
Rule 2: When you see a crap file or folder DELETE IT.

I chose crap because it is short and easy to remember. It also doesn’t often crop up naturally in filenames from other sources. You may have another name or acronym that appeals to you. Start using it today and enjoy the extra hours I offer you in 2019 and beyond.

Alexa Command Line Interface

Last week I found a brilliant YouTube from Dabble Lab that explains how to use the CLI and how to get some Alexa templates to get started with your own skills development on Amazon. I have been battling with both the CLI and the IAM site for several months now. Today I have “User: arn:aws:iam::123456789123:user/debugUser is not authorized to perform: iam:CreateRole on resource: arn:aws:iam::012345678912:role/ask-lambda-basic-starter” when I try to deploy from CLI. At least can I see what user I am using. This will help a lot! I will now try to find CreateRole on IAM. The “helpful” 2017 AWS IAM setup videos are grossly out of date and I have been COMPLETELY CONFUSED by their tutorials. There are users, groups and roles to do my head in but I can’t find the required “CreateRole” mentioned in the message. There are heaps of others which are difficult to read in the drop-downs because the columns don’t expand. I added a group and a role but didn;t work so deleted.

Now I an trying this way which failed because you can’t create the create-role until you have one. Chicken or egg!

OK just watched ASK-CLI installation to see if I did that right. No clues there. Just another 2 hours wasted today.


Amazon Alexa Dot

What a wonderful device I purchased a couple of years ago, an Amazon Dot. But like a lot of women she can be quite frustrating to interface with!

Veranda Control

Louvre Roof

I recently purchased and erected a louvre roof from China which includes two controlled louvre areas and three curtains. All these are controlled by five 433MHz wireless controllers. Naturally, I would like Alexa to control these and I know she can. She needs a little help to talk to them but this is solved by Broadlink with their brilliant Smart Universal Remote Control. After getting one of these I was able to program all five louvre roof remotes (and my TV & sound system) into the Android IHC app and control them from my mobile phone. I can also set scenes where I can open or close all five with one command.

Alexa Mqtt Bridge & Printer Server

Raspberry Pi Zero W

I also run a Raspberry Pi Zero W as an MQTT server/broker in my home and naturally I need to have Alexa talk to this in order to interface with my home IoT devices. I implemented this NPM module and can open and close garage doors with a command like “Alexa, Geoff garage on”. By using this magic module, Alexa thinks the bridged device is a light.

I had to add a new task to the Raspberry Pi recently. I have a non-wifi printer that lives in another room apart from the computer so I added a printer server.

Node-RED Alexa Home Skill Bridge

I looked briefly at this solution but it requires registration with a third party service and I want to use my in-house server. See


Node-Red node for Amazon Alexa Skills Kit (ASK).

To Be Continued……..

One-time Cat Feeder


I knocked up this quick & dirty solution just before leaving my cat for a weekend away. Ashly (cat) is quite happy with us going away for a few days AFAIK but is now geriatric and on thyroid medication so I decided to address this. I needed a wooden box with a lid I could hinge so I used an old drawer I was throwing out. I sawed a couple of cuts in the back, drilled holes and used cut-off nails for hinge pins. I pulled out a 12V solenoid from my parts box and bent up a bracket to mount this on. I just used my bench power supply for a 12V supply. The flap is vertical so needed a spring to ensure it opened. Only trampoline springs in my spring box!! Ball point pen spring considered, finally remembered a couple of neodymium magnets I have so I mounted these with cable straps so they repelled each other and this works a treat! Finally, the brains; a Sonoff S20 WiFi wall socket with a timer setting on E-Welink on my phone to turn on the power supply at feed time and another a minute later to turn it off. Tested it through a cycle then loaded it with food and medication and shot off for a weekend family reunion. It was weighed down with a pot plant (anti-cat tamper) on an outside table in a covered veranda along side his bed and water. Ashly would be very aware of it because it had no baseboard and the wet food smell would be emanating.

I can actually control those wall switches from my mobile phone but had not previously tried that before so did it the timer way. Got home Sunday, bingo! Evidence of cat pig-out and most food gone.

Colloidal Silver Controller

Make low cost Colloidal Silver at home with this easy-to-use, 240v plug-in generator.

My wife recently bought a Colloidal Silver Generator from Health House here in NZ. It is simple to use but requires some attention. We make 1 litre a time in a “quart” preserving jar. Basically our brew needs a get-going period followed by several electrode reversals. The electrodes are wiped clean with a paper towel between cycles. What a great opportunity for me to semi-automate this process! I chose an ESP8266 product and used a Wemos D1 Mini 4MB from Banggood. It grabs its power from the generator supply using a buck converter to give 5V supply. A dual relay board to switch the polarity of the electrodes. There is also a Buzzer Module an LED indicator and a push button. During operation status information is given.

  • short beep at 1 minute intervals – waiting for fizz
  • led flashes at 1 second intervals shows cycle number
  • short beep and led flash at 1 second intervals – clean electrodes then press button
  • led flash continuous 1 second ON and 1 second OFF when complete
Bill Of Materials
  • Wemos D1 Mini
  • Buck converter
  • Dual relay board
  • Buzzer module
  • LED indicator
  • SPST momentary push on switch
  • 2 pair 4mm banana plug
  • 2 pair 4mm banana socket
  • Plastic project box

Please note: These are affiliate links. I may make a commission if you buy the components through these links. There is no extra cost to you.
I would appreciate your support in this way!

Emic 2 Text to Speech Module

I have been playing recently with an Emic2 Text-to-Speech module. You can buy these from your favourite web store. My USB serial board was probably from AliExpress. Get one with the 3.3V/5V level selection switch for more versatility with different products you may wish to connect to. I use Windows 10 so I downloaded Termite, a simple free RS232 communications tool that enables me to send commands to the text-to-speech module via the USB UART board. Communication parameters are 9600,n,8,1. You need to power the Emic-2 module from a 5 Volt supply capable of half an Ampere because it idles at about 300 mA and peaks to about 500 mA when using a small speaker connected to the on-board amplifier..

The voice output lacks the quality of Siri, Alexa, Cortana or Google Assistant type products, but does a good job of converting text to speech on a self contained module with no computer assistance. Here is an English sample wav file.

I will connect it to my MQTT server via an Arduino Nano or Mini in a future project for making announcements when required from my smart-home project.

This is my test hookup.