Public IP Address Notification Emailer

Sometimes you want to know the IP address of a remote server, but it can have a dynamic address that can change. There are services that can provide this service, but I wanted something free and simple that also provided a heartbeat message from the remote server.

The idea is to have a bash script on a cron job that will call a remote server. This remote server will then know the public IP address of the caller and can send the information to an email address. Now the email messages will have the remote IP address and the emails also serve as heartbeat messages.

I have put the code I use to do this in GitHub for anyone that may want to do something similar.

A short coming of this system is you need to wait for the next cron run to get a changed address. That was not an issue in my application.

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Leitner rack on 1999 – 2006 Chevrolet Silverado 1500

Leitner no longer claims to have fitment for their racks on 1st Generation Chevrolet Silverado 1500 trucks. But I measured and measured, and it seemed to me that the racks for the current Silverados would fit. I contacted the guys at Truck Brigade and they said according to their measurements, it should fit. So I pulled the trigger and bought the rack. As you can see in the picture below, it fits. Thanks to Truck Brigade for taking the time to check my measurements, and Chevy for keeping the bed size stable. This is a standard box, Extended Cab 2006 Silverado.

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Minka-Aire Fan Reset Remote Code / Frequency RCS213

The 3 year old was playing with the fan remote and managed to take off the battery cover and scramble the code / frequency switches. It ends up relinking the fan and remote was easier than feared, but not knowing this, I tried to do it the hard way first.

Thinking I needed the get the code off of the fan receiver, I took the fan down. But the receiver had no switches on it. Instead there was a sticker saying to reprogram, remove power from the fan, and within 60 seconds, press the fan off button for 5 seconds. The light will flash to indicate the remote is paired and you are done. I did these steps and it worked as claimed. Note I went to the breaker box and turned off power there to make sure the fan had the power removed.

Posting this in a blog post in-case it helps someone else, and to remind me to not take the fan down the next time the codes get scrambled by our little cutie.

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Frigidaire Gas Range FFGF3053L How to Remove Top

I had some flaky igniters on a Frigidaire Gas Range Model FFGF3053LSF but was having a hard time finding out how to remove the top. It is obvious you need to remove the screws on the top that attach the burners, but it was not clear how to get the top to disconnect from the range body. Below are the 4 screws I needed to remove, after which I was able to pull forward and up and get the top off. The knobs are easy, just pull them off.

FFGF3053LSF front plate screw left
FFGF3053LSF front plate screw right
FFGF3053LSF top plate screw left
FFGF3053LSF top plate screw right
What it looks like under the hood. The front left burner has been removed for service.

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Prevent Slab, Copper Pipe and Ice Maker Leaks

We just had a bad copper pipe slab leak and have been dealing with on and off problems with the ice maker leaking. It is a long, sad story; to sum it up: we had to repipe the whole house, and ended up with a pressure gauge on the house plumbing. It was then I noticed that the water pressure was sometimes spiking to 100 psi. At first I thought we got a bad pressure regulator from the repipe company. They put a new one in, but the random high pressures continued. I finally figured out that when the hot water heater was heating the water, the pressure would rapidly rise. Makes sense, heating up water causes it to expand, and now that the plumbing system has no leaks, the water has no where to go and the pressure climbs. The solution, install an expansion tank where the water feeds the hot water heater. I also put a pressure gauge in so if I ever look up and see the pressure is not at 50 psi, I know something is not working correctly.

I get the feeling that if I had installed the expansion tank years ago, the copper pipes would have lasted many more years. Live and learn. Below is a pic of what the install looks like. Parts cost about $100. Repipe: $8,000 plus the cost to repaint the walls that got cut open.

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Fix a Leaking Tile Roof on the Cheap

On rainy days buckets would need to be put out to catch water dripping from the ceiling. In the past, I would call a roofer and get out a pile of cash. During one of those wallet thinning meetings with a roofer, he explained to me that often the valleys of the roof is where the leak is coming from. Roofs will be built with the tiles touching each other in the valley causing leaves and dirt to build up blocking the water from running down the valley. The build up can get so bad that the water will flow sideways past the flashing, break down the tar paper, and leak through the roof. It can get so bad that the wood sheathing can rot away (has happened to me, time to call the roofer).

Tracing the new leak up the wall and into the attic, I could see the leak was at a valley. I got on the roof (20 foot high, so took things slow), and did my best to clean out the junk that had built up in the crack of the valley. But there was little room between the tiles to work in, and while cleaning helped, the leak continued. So I put together a few tools, and spent an afternoon on the roof cutting open the valley to look like I have seen done by roofers.

Below is what it looked like working up the valley. The left has enough of the tile cut back to open a channel for the water to flow down the flashing in the valley. The right side shows progress working through the layers of tile and the 4 1/2 in diamond saw used to cut the concrete tile.

Cutting open the valley of a tile roof.
Dirt builds up blocking water from draining down the valley.

It was slow going, marking where to cut, shimming under the tiles to protect the flashing, cutting tiles, and chipping out the part to be removed. But since clearing a gap between the tiles, the rain rushes out and the leaking through the roof has stopped.

Tools used to cut open the roof valley.

This is not a good project for the new DIYer. Working on a sloped roof can be very dangerous and mistakes can damage a roof requiring expensive repairs. But I was able to spend a few hours on my roof and stop a leak for very little money. For tools I used a cheap angle grinder, a diamond cutting wheel (less then $20), a wide ruler and white grease pencil to mark the cut lines, ear protection, dust mask, eye glasses, gloves, and a pick to shim up the tiles and chip out the cut tiles.

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Ion Block Rocker iPA56 Bluetooth Aux Port Repair

Our 2 two year old, cute and destructive, directed her wrath at my Block Rocker breaking off a mini plug in the aux port. I tried without success to get the tip of the plug out of the aux jack and moved on to swapping out the 3.5mm jack for a more toddler proof 1/4″ jack.

To get the top off, remove the the 4 screws in the front, the 4 silver corner caps and one small screw in the back near the pull up handle. If yours is the same design, you should be able to gently pull up the top and get to the control electronics as seen below, moving slowly as to not damage the wires that are connected to the base.

The mini jack is sealed on all sides, preventing me from getting to the broken off plug tip that was shorting out the jack. Not seeing another option, I used a soldering iron to carefully heat up and work out the jack. Once the 3.5mm jack was out, I tacked on a white, black (gnd), red wire set to run to the 1/4″ jack mounted to the top as seen below. From what I can see, the white and red signals are summed on the board to convert stereo to mono.

Below you can see the 1/4″ jack on the top, and the empty 3.5mm aux jack. Everything seems to work the same, the new jack is much stronger, and if it did get broken, it is easy to pop off the top and get to the open access jack from the back.

Happy Block Rocking!

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Simple Script to Make Rotating Backups of a Directory

There are times where I want to make a simple, rotating backup of a directory so I can go back and look at how thing were in the past, or push a backup to another location. Below is the basic script I use. It makes a timestamped tgz, and then deletes the backups older then some number of days. file contents:
tar -czvf ~/devbak/public_html_$(date +%m%d%y-%T).tgz ~/public_html/* –exclude=*work* –exclude=*docs* –exclude=*.log –exclude=*.svn* –exclude=*.git*
# command to delete old backups
find ~/devbak/*.tgz -mtime +7 -exec rm -f {} \;
It puts the backups in a dir “devbak” and excludes a number directories that can bulk the file up, but not be very useful for the intended purpose. You will certainly need to look it over and tweak the script for your purpose.
To have it automatically run once a day, add the script to a cronjob.
You can edit you cronjob with the command:
crontab -e
Example line to add:
# 0 1 * * *   /home/user/cronjobs/
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Versatile Voltage Divider / Isolator Interface for Arduino / Raspberry Pi

In working on various projects, I often need to interface signals to the input of an Arduino, Raspberry Pi, BeagleBone, or custom digital input. I wanted to be able to handle signals from 5V DC, 24V AC (sprinkler controller valves), up to 240V AC (to monitor my well pump run time). It needed optical isolation and an indicator LED to make it easy to see when a signal is active. I also wanted screw cage connectors so I did not not need to deal with crimping headers and larger wires can be used when monitoring a signal some distance away. So I put together a basic building block type circuit board that can be adopted to a wide range of uses. Below is a image of what it looks like. You can see it uses all through hole components. Since I will be using this in many different ways, I did not want to hassle with tracking down SMD components in the different values I will need. Also through hole makes it easy to change the values in the field when I am away from surface mount soldering tools.


If you just want to see how it works and make one yourself, here is the schematic. The values will vary and not all components are needed depending on the application.

I wrote up some application notes to keep track of the values and part numbers I have used.

Or if this looks useful, I put the blank boards up for sale on Tindie:


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Solar Car Cooling Fan

I live in Southern California and getting in to your car after it has been sitting in the sun is only enjoyable for those that consider hanging out in a sauna while dressed in your finest Brooks suit a good time.

So I did some searching on the InterWeb thinking surely someone is selling a solar powered fan I can stick in my car so it will not be so hot when I get in. I did find a few solar car fans for sale, but they all have horrible reviews. So I thought it must be that they are using cheap fans and solar panels that are too small. I envisioned that if I used a quality fan connected to a large solar panel, it will keep my car cool, and surely others are looking for the same thing–I can sell it and make millions.

So now you know the dream, here is the reality: I took a high quality fan, mated with a large solar panel that covers the entire rear dash of my car, and left a data logger in my car to see how much it lowers the temperature. The result, I think I was able to notice a 2 – 3 degree difference. I say “I think” because day to day the outside temperature is different and you can not be sure if the difference is from the fan, a lower outside temp, or some combination of the two. The fan works, you can feel the hot air flowing out of the car. I guess it is just the laws of physics–the heat energy coming in from the hot sun is dwarfed by the amount of heat the fan can pull through the cracked windows.

You can see the pictures of what I put together below in case you want to give it a try. With a bigger panel and more fans, I am sure at some point you can get a decent reduction in temperature. Actually someone has already done this:

Look at features.

Here is what the Maybach does: “In sufficient lighting conditions, five rows of six silicon solar cells generate approximately 60 watts to power the vehicle ventilation fans, after the engine has been shut off. Solar module is included with the Electrotransparent glass roof package.”

If you are thinking, forget building a solar panel power car cooling fan, I’ll just get me a Maybach. Read all about these rolling luxury transportation systems here. I quickly came to the conclusion buying some extra Brooks suits to soak up the sweat would be a lower cost option.

Car fan running and off on alternate days

As for the millions I was going to make selling Solar Powered Car Fans, I guess I will live under the weight of my broken dreams and get back to work on my other side projects:

Schedule My Employees

High resolution control room amplifiers

Used by some of the world’s top mastering and recording studios

(Pic of my engineering/test unit)


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