The Dow Hurst Average – The Tutorial for Advanced SSH techniques and Screen command usage — SwitchDoc Labs Blog

Advanced SSH techniques and Screen command usage – The Dow Hurst Average Editors Note:   More advanced SSH usage and the elusive “screen” command!  SwitchDoc Labs is pleased to welcome our new columnist Dow Hurst to the SDL family.   Dow has a great background and really likes showing people of all abilities to master…

The Dow Hurst Average – The Tutorial for Advanced SSH techniques and Screen command usage — SwitchDoc Labs Blog

A Difficult Story

The “discovery” of the children’s bodies found on the property of the Tk’emlups te Secwopmc First Nation in Kamloops, B.C  has captured the attention and the hearts of Canada. This residential school operated from the 1890’s to the 1960’s and now in 2021 pronouncements are circling the globe claiming a “discovered” “mass grave”, where the […]

A Difficult Story

Wanscam K55 Up Date

Well it has been a couple of weeks since I mount this camera outside to put the device to the test. I purchased 4 – 18650 3000 mHa lithium batteries to run in the camera. I charged them up with the charger that came with the batteries so they were fully charged. When they were placed into the camera, the App advised they were 100% at the time of the mounting. Now setting the App up, I had the camera send updates to the phone on movement that was detected by the PIR in the camera. Well this was a bit of a mistake as there is a bus that travels past the house a couple of times per hour, never mid the rest of the traffic throughout the day. I changed that so that the PIR did not trigger all the time. The second and third days of use the camera did not bring the batteries back up to the 100% mark.

The camera is mounted so that the solar top is facing the southern sky for the large majority of the day. After the third the battery was down low, less than 20%. The following day was very cloudy and I wonder how well the batteries would recover. Well, then did not make it back to 50%. Then for the next few days, the sun was not always visible. Then two days of rain came.

After the rain, I attempted to connect to the camera, but it would not. A couple of days of no connecting I decided to take the camera down as I felt the batteries were probably not charged and I was correct. Dead! So, since the design of these solar cameras have the charge port/power port inside the battery compartment, the camera has to be removed from its mount and then all of the screws removed from the belly of the camera to get at these ports and batteries. I get it, they want it waterproof, but it is a pain to have to run out to the camera every time it stops working or the batteries are dead. Especially in climates that are sure to dip below freezing and then some.

The SAP HD App needs a lot of refining. The WiFi would not respond once the camera stopped working. I could not delete the camera from the App either as I thought I might try to re-install the camera in the App. But for some reason, you need to have a connection with the camera in order to delete the camera.

In the end, I ended up pushing the reset button on the camera and starting all over. I’m not sure this camera will survive the winter at the rate these batteries are going. Short days now will not allow the batteries to fully recharge using the sunlight. I would not recommend buying this camera for a shady area of your yard.

While the camera was up and running, I tried my darnedest to get the camera to connect to my Synology system to no avail. From the research I could figure out, the K55 has no protocols that will allow it to connect to the NAS. Some cameras that were looked, their specs showed 6 or 7 protocols such as http, https, etc.

I’m totally sold on the solar aspect for surveillance around the yard, but this camera I don’t think will cut it. I guess more research will need to be done before the next purchase. Perhaps a separate solar panel.

Until the next time, stay safe and keep the technology coming.

March 8, 2020

So, the winter has almost past and the camera has been outside all winter. I was worried the batteries would not maintain their charge. The lowest percentage of battery I noticed when spot checking was low 80’s. Today the batteries shows 100%.

I’m still trying to figure which recording mode is best and where to actually store the clips. There is a cloud function on the app and of course the micro SD card. I think the card is my best choice for now. The recorded video is clear, but I can’t seem to get the 1080 resolution to stick, VGA only.

The recording of the video doesn’t seem to be working. I set the camera to record continually and yet nothing seems to be on the storage card. I removed the motion alerts as there were continuous alerts as the bus passed by and the Co-Vid19 walkers. More tinkering needs to be done.

The quality of the images of the live view is fantastic. Let’s get the recording to work and the 1080 resolution to stick.

Wanscam K55 Solar IP Camera

I’ve been looking a for a camera that I could install outside, not have to worry about running Cat5 cables a long way or not having to try and find a plug in. My first thoughts were to find an IP camera. That way, no need for any Cat5 cables and I could just run it off the WiFi. That takes care of the cables, now for the plug in. Solar seems to be a never ending topic in this day and age of the “save the planet”. I’m all for solar energy, so the search for an IP camera with solar powering.

I follow a gentleman’s online posts and it happened he was posting about solar IP cameras a few months back. This started me thinking that one could purchase a camera for not all that much. He was getting his product from Banggood. I have purchased from the site before and have had good success with the items I’ve purchased. I ventured to the site and started to peruse the Solar IP Cameras.

I found the Wanscam K55 which I thought would be a decent camera for its price. Here are the specs on the camera:

Specification :

OS & Processor Huawei LietOS system, Hi3518EV200+GC2238
Resolution 1080P Full-HD (1920×1080); Sub Stream: 720P(1080×720)
Mobile App Support QR code scanning to view on iOS iPhone, Android Smartphone. App: SAP HD
TF Card Record Support max 128G TF SD card. Support scheduled record, snapshot, video playback
Lens Type Lens: 3.6mm, 4x digital zoom
Video 2.0 Megapixels 1/4″ CMOS sensor. Image Compression: H.264
Audio Two-way Audio, Built-in Microphone & Speaker. Support echo cancellation and sound adjustment
Night Vision 8Φ850mm IR LED Lamps, Night vision distance 10 meters.
Wake Up Mode Support PIR detection wake up and APP wake up
Alarm Support m otion detection & PIR detection, Rapid push notification, Snapshot to save TF card
Push Support equipment push and PIR push
Onvif Support standard Onvif 2.1 protocol
Online Visitor Support max 6 visitors at the same time (First Stream:3 visitors; Second Stream:3 visitors)
Power consumption Stand-by Current 250uA
Working current 170mA
Micro USB adapter charging & solar power charging
Power Supply DC5V/2A. Support 4*18650 battery(Not included). Solar Panel: 5V
Wireless WiFi, 2.4GHz 802.11b/g/n. Smart one key WiFi configuration
OSD Support camera name ,date and time information show on image
Working Humidity 95% RH; working temperature: -10~70°C
Size Item: 18x8x7cm (LxHxW); Packaging:22x20x8cm (LxWxH)
Weight N.W.: 500G  G.W.:800G (Note: Actual Weight Final)
Package Include IP Camera, Manual, Screws

The camera is powered by 4 18650 batteries which I learned another lesson on those looking for the right battery to purchase. The internet has numerous places selling the 18650 battery with 4000 mAh all the way up to 9800 mAh. By researching which would be the best to purchase I found out the 18650 battery can only hold a MAXIMUM of 3500 mAh. I mean it is obvious that anyone would want to purchase the maximum mAh in a battery. Right? So I settled with 3000 mAh batteries.

The camera can run on either battery power or via micro USB cable. The only problem with the latter is the battery jar cover has to be removed to get at the port of the micro USB. This will pose a problem exposing the micro SD card slot, power and rest buttons as well as the micro USB port. So, I think the only proper way to run the camera is with the batteries. I think that is the whole point of the system, solar, batteries, IP, etc.!!

Package includes :

1 x Wanscam K55 IP Camera
1 x User Manual
1 x Screws

You’ll have to purchase the batteries separate. Again read above about the batteries. Be careful what you purchase.

The camera is basically activated by installing an App on your phone. The is available for both Android and iOS. The manual has a QR code which you scan to install the App. The App is called SAP HD. I found the App not all that user friendly. Connecting to the network was easy, but the rest of the look and feel of the App was not good. I was trying to locate a sub menu to turn off the blue light on the from of the camera and I could not locate. It goes to sleep and it turns off then, perhaps that’s all there is. There is a place to change the recording from VGA to 1080p. The video is still very clear, either way. I can toggle it back and forth, but it always seem to stick on VGA no matter how many times I think I have changed it. The App needs a lot of polishing.

I want to be able to connect the camera to my NAS, but at this point, I’m at a loss on how to get it to connect. The NAS security software does not recognize the camera and does not find it on the network. This part of the experiment is not over yet. For the time being I have installed a 128 GB micro SD card. The recording of the camera loops over the oldest recording video once the card is full.

Tevo Upgrades – Dual Z Axis

Well, I’ve had the Tevo Tarantula for about 3 months and by rights, I’m behind most owners in doing upgrades to the “Spider”. According the Facebook page, most owners are printing and purchasing upgrades for the printer right from the start. I have printed some items out to house the power unit and the circuit board. Not really upgrades, more ascetics.

If you search the Internet for upgrades for the printer, you will find a list of many things to do. The first thing I’ve chosen is get the Dual Z Axis.  This kit will keep the movement of the “Z” axis moving completely level and parallel to the heat bed, thus, the print is smoother looking. Having two -Z- axis motors with the threaded rods can help ensure stability of the -X- axis during print and can, overall, reduce wear on the mechanical components.

I purchased this Banggood Dual Z Axis. At the time of this writing, the kit sells for $52.13 CAD. I was lucky enough to get the kit for about $10.00 less.

As you can seen by the images above the kit doesn’t have much to it. (Large image is missing the stepper motor). The other images show the kit installed and the installation follows the same lines as the first z-axis motor and screw assembly.  There is an excellent video by ruiraptor titled TEVO Tarantula 3D printer – HOW TO improve your printer – Part 13 (DUAL Z MOTOR). This video walk the installer step by step thru the installation and the fine tuning so it will work correctly with the original z-axis motor and screw.

There are three ways to connect the  motor to the circuit board. The motor wire that comes with the kit allows the motor to be connected in parallel, serial or extra driver. The video shows the Pros and Cons of each type of connection. I chose to connect the motors by way of parallel. It seemed to be the most straight forward method.

Every little tweak and add-on to this printer seems to make it better and better. The next upgrade to the printer will probably be the replacement of the Y-axis rubber wheels to the metal ball bearing rail. With that, an upgrade to the heat bed frame.  Stay tuned.

Tevo Tarantula i3 Prusa Printer – Printing – Part 3

So, you’re all setup, the printer is built and the electrical is wired and you want to print some. The itch is really getting to you. But what does one print out and where does one get files to print. One of the best places for getting files to print is from Thingiverse.

Before we get the printer all cranked up, we have a few things that need to be done. The printer circuit board  comes preloaded with the firmware needed to get the printer printing. In reading through the posts on the Tevo Facebook group, I decided to upgrade the firmware to Marlin Firmware. The firmware upgrades have to be performed with the aid of an Integrated Development Environment of better known as an IDE. There is a lot of IDE’s, but the one to use is the Ardunio IDE. You can download a copy of it for you particular Operating System here. Version 1.8.5 was the flavour of the day at the time of this writing. Once downloaded and installed, start it up and use the menu and navigate to Tools>Boards>Arduino/Genuino Mega or Mega 2560. The Arduino Mega 2560 has the same processor as the circuit board on the Tevo Tarantula printer, hence the reason for the use of the Arduino IDE.


Once the board has been selected, you need to connect the USB cable that came with your printer to the computer. When you click on Tools>Port, you should see the board and you just have to highlight it. The menu item Tools>Processor can be left as it is.

Head on over to Marlin Firmware and download the firmware by clicking on the green download button. Read the instructions that displayed on the page.


Once downloaded, unzip the file making note on where it is located. What I like to do is move the unzipped directory into the Arduino directory. In Mac that is /Users/user/Documents/Arduino/, Linux /home/user/Arduino/ and Windows /User/Documents/Arduino/ (I believe). Now open the Arduino IDE and click File>Open and navigate to to where the directory was placed. This should look similar to this once you drill down into the ../Arduino/MarlinTarantula-EasyConfig-1.1.x/Marlin/ and locate the file Marlin.ino. these .ino files are known as sketches in the Arduino IDE world.

Double click or single click if in Linux and open the configuration. I never did any changing of any of the files, but there are a million different things that could be changed. You screen should look like this:


Don’t worry about the Updates pop-up in the bottom left of the screen if it shows up there. Now at this time, I would just leave everything the way it is and upload the sketch to the circuit board and see how things go. Once one gets use to the process of uploading the sketch and playing with the LCD, you can try to change things to meet your needs.


In order to upload the sketch, you must have your printer connected to the computer, the printer needs to be recognized under Tools>Port in the IDE. If these are all good, then you click on the “right arrow” as seen in the image above. There will be lots of text scrolling up in the lower, black area, of the IDE window. As long as you don’t get a bunch of Orange text in the lower black area, you should be good to go. There are lots videos on Youtube.

The last thing you need to do before you sent that first print to the printer is to level the bed. This is very important and should not be over looked. You should give the bed a quick leveling prior to all prints. Once you’ve done it once, it will be like riding a bike. Level Bed. I use a small piece of paper and with the falling procedures.

Using the LCD, press the button down and select “Prepare”. The scroll down and select “Home Axis”. You should here the printer move around. Once the printer has homed, scroll down on the same menu and select “Disable steppers”. The bed can now be moved freely, but do it slowly as the electricity can back feed into the main circuit board.  Move the bed so the left front corner (0,0) is directly under the nozzle. Place the paper between the nozzle and the bed. Adjust the bed so the piece of paper as a bit of friction between the bed and nozzle. It does take a bit of feel. You then move the nozzle to each of the other 3 corners adjusting each in the same manner. Then repeat the process again.

Give your print a go. You can either use the USB cable connected to the printer board or save the file to the SD card that came with the printer. The choice is yours, I prefer the cable to the printer method, but go a head and try both. I just find moving the SD card around a bit of a pain. The cable connected is a bit easier.

Now, something I’ve not touched on is how do you get the file you downloaded from Thingiverse or wherever else you my get them. The file I use is the stereolithography file or .stl for short. These files are the most common form for moving your project to the printer. These files need what is called a slicer to get the CAD file from the computer to the printer. There numerous slicers and a quick Internet search will give you a list of free and paid versions to which you can make a decision on. I like to use Cura. I seems to just work for me. There are a million tweaks to do to the software and that is a whole other topic. I have looked a Slic3r, Repetier, Ideamaker and Ponterface.

In Cura, use the open file and find your stl file and open it up. As I said, there are a million tweak you can do, use the recommend settings for now. I use the “fine” profile and this seems to work just fine. It should tell you how long it will take to print and the options of where to print. SD card, to a file or to the printer via USB. Don’t get too excited, most of the prints take hours. I even looked a print for my son that was going to take 3 days plus!

Remember, there are lots of resources on the Internet.

Play around and have fun.


Tevo Tarantula i3 Prusa Printer – Wires – Part 2

So the printer is built and all of the carriages move nice and smoothly.  Now there is a wad of wires, switches and electrical parts that need to be all connected in order to make this printer, print.

If you remember at the tail end of Part 1, I gave a link to a YouTube video which, at the beginning of the video, it showed a few tools and supplies to get. I would recommend purchasing these supplies and getting a hold of these tools. It will make the electrical portion go a bit easier. Place the ferrules on the ends of the all of the wires that connect to the terminal blocks on the circuit board and crimp them.

I found that trying to twist the wires and place them into the blocks did not work. The wires came out every time the printer was bumped or touched. I did order a mosfet for the heat bed, but after using the ferrules I may just leave things the way they are. I  would suggest installing the wires into the circuit board while the circuit board is not mounted on the printer. I mounted the circuit board on the acrylic mount parts, using required mounting screws and steppers, then attached the electrical wires.


There are only 6 wires that need to be placed into the terminal blocks. Once all of the wires are secured, you can mount the circuit board onto the railing on the printer.


In the above image, left to right are the following:

  • Nozzle, thin red wires and it does not matter which side of the block they go in.
  • Heat-bed, polar requirements, negative on the left, positive on the right.
  • Main power, polar requirements again, positive on the left and negative on the right.

Mount the board to the printer and secure with the M4 and “T” nuts. I have read people have installed the circuit board with the electrical wires on the top. Reason being, the wires were less likely to come out. Your decision. Once this done, the rest of the wiring is a snap, literally. In the back of manual, there is a schematic drawing for the wires. I followed the drawing and plugged in all of the wires to the board. Next attach the wires to the main power supply. I would recommend using wire connectors and a crimper to place ends on these wires as well.


The two small 40 mm fans, nozzle and circuit board, are wired to the power supply not to the circuit board.

Once the cables and wires are plugged into the circuit board, including the two ribbon cables that go to the LCD, you can place the cover onto top of the circuit board. Now plug the power cable into the wall and see if things power up.

In the image in the above right, the fan and mounting pate that covers the circuit board is laying on the power supply. I’ve tucked the cables and wires back onto the board and placed only 2 screws to hold the cover on top of the circuit board. I want to try and find a way to clean up the wires and cables. For now it is working. I have placed a couple of the wires from the rear of the unit, into the railing of the frame and then covered the slot with one of the 3 long, thin, plastic and”U” shaped parts that are located on the bottom layer of the box, Layer “C”. There is the heavy coil, black housing that one can stuff cable into and I did use part of it to hold the wires from the heat-bed. I have seen lots of wire/cable tie ups on Thingiverse that you can print once your ready to go.

At the end you will have a limit switch and a heat sensor left over. These are both spares and there should be some of the small bags with screws, washers, spacers and nuts. These too are spares.

All in all the electrical part of the printer set up did not go too badly. The biggest problem I had was keeping the power and the heat-bed wires connected to the circuit board. After that, I had a small glitch in the which motor was connect to which port on the circuit board. Not sure why I could not get thru my head which was the “X” and which was the “Z” stepper motors. Once it was pointed out the motors may be connected to the wrong connector on the circuit board, the “Home All” command on the LCD worked as it is suppose to. So, take your time and make sure the connectors and wires are in the correct ports.

The Limit Switches are the next thing to focus on. The “Y” axis (heat-bed) has one of these switches and if you mounted as per the installation video, it should be just fine where it is. Mine was just fine. The “X” axis (slides back and forth) has the switch mounted on the carriage and I never had to adjust anything there either. The “Z” axis (goes up and down) has a limit switch mounted on a bracket  on the back of the frame, near the bottom. Kind of behind the circuit board. This bracket/switch will need to be adjusted and it may take a few cracks at it.  This ties into the bed (“Y”) leveling. Once you get the bed leveled and the nozzle just right, lock the bracket in place.

I’m sure there is a lot I’ve missed in this part, but if you’re stuck, head on over to the Tevo Facebook Page. Lots of very knowledgeable people that can help out.

In  Part 3, I’m going to attempt to showing off the LCD and heading towards your first print.