Category Archives: Projects

Craft, Hardware, or Software projects I’ve done

Google Pixel 5A – Colorful Snow screen flashing problem – Resolved by re-flowing solder on motherboard

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My wife’s Google Pixel 5A phone developed a problem where the screen would “flash” between a colorful snow pattern and was it was supposed to be showing. It started out slowly, with intermittent flashes, but quickly got worse where the screen was barely ever showing what it was supposed to. [It also does not accept touch input events when “flashing” the colored snow pattern..]

I was able to retrieve the data off of the phone by heating the entire phone up, but this was a temporary fix as the problem returns as soon as the phone cools down.

I was able to fix the problem (hopefully permanently) by completely disassembling the phone, extracting the motherboard, and hitting it with 5 minutes of heat from a 300 deg c hot air rework station. (I aimed the hot air at the video connector, and then at the covered set of chips right above the video connector (opposite from the battery connector), as I figured that was the most likely location for the video graphics chips. I still don’t know which EXACT component had the problem, but allowing the solder joints in that general area to re-flow appears to have fixed the problem, as when I re-assembled the phone it is working perfectly at room temperature.

Building a Telescope Tripod dolly (Meade LX-200 12″)

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I built my own Tripod Dolly with casters & Leveling bolts (out of 2×4’s and plywood) for my Meade LX-200 12″ with Giant Field Tripod (the one with the 3″ diameter legs).

I was originally thinking it would be just so I could play around with the telescope (move it in and out of the garage) and get a feel for things until I decided what commercial dolly / truck / cart to buy, but I’ve been so happy with the results that I think I’ll just use it permanently.

Tripod Dolly built from 2x4s and plywood

 

I’ve got a short 5 minute intro video here (which links to a full 40 minute how to build step by step video if you decide to follow along and build your own):

Also of potential interest to people with the Meade Giant Field Tripod is that I modeled the tip of the tripod legs and designed a 3D printed bracket for holding the tripod tips securely in place on the 2×4’s…[Of course, you could just drill a 1″ hole at a 55 degree angle, but if you’ve got a 3D printer everything needs a custom bracket….]

You can find the 3D model & OpenSCAD design file on Thingiverse here: https://www.thingiverse.com/thing:6826864

 

Google Pixel 5A screen flashing “colored snow” – Recovering the photos.

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Pixel 5a phone showing the USB Preferences screenGoogle pixel 5a showing the "colored snow" pattern

My wife’s Google Pixel 5a phone suddenly developed a hardware fault that presents as a “colored snow” screen flashing over the entire phone display. While the “colored snow” pattern is on the screen, the phone does not respond to touch events.

However, when the colored snow pattern is NOT showing, the phone display goes back to showing what it should be showing, and it will accept touch events.

The difficulty is that the speed of flashing is very fast (on the order of 0.5 seconds) so it is difficult to read the screen and push buttons or UI areas effectively to do anything.

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Is your camera image sensor dirty, and if so, how do you clean it?

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Do you have dust and foreign particles on your camera’s image sensor?  If you have an interchangeable lens camera body, you probably do. But in many cases, a few random specks of dust won’t be detectable in normal photography.

However, if you have visible spots showing up in your images, you know it’s time to clean your camera image sensor. For example, in this closeup of the N2A Goodyear Blimp, if you look closely at the end of the black hand drawn arrows, you can see the results of dust on the image sensor of my second-hand A6300 camera. [Obviously, all dust is the fault of the first owner, and I can keep claiming that until after I clean it.]

Photo of the goodyear blimp, with small dust spots evident in the photo.

Now that you know there are at least a few pieces of dust/debris on your image sensor, you can characterize just how bad the problem is by shooting a “flat” image.  Point your camera towards a clear patch of sky, put the lens in manual focus mode and defocus it, and take a photo that is just slightly over exposed. [Note that to take a true astrophotography flat you need to do more than this, but for the photos below I didn’t bother. You risk having cloud shapes show up in your flat image by not having a tight white cloth over the lens….but since we are just looking for dirt it’s not critical that your flat not have gradients in it.]

defocused image showing dust and debris on the sensor

If you have a lot of debris on the sensor, it will be easily visible directly in the image. In the image above, you can see I even have some type of fiber or thread (middle right). This is an example of a sensor that definitely needs cleaning.   But you can also digitally enhance these images to highlight the debris more, which is useful in cases where the amount isn’t as bad.  Just import it into a photo editing tool, and use the “auto adjust input levels” feature to get something like this:

digitally enhanced image showing lots of debris on an imaging sensor

With digital enhancement this looks super bad, but as you can see from the image of the Goodyear Blimp above, even this level of dust and dirt doesn’t mean you can’t take a mostly usable photo with the camera.

 

How to clean your image sensor

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Bearing Replacement on an iOptron Cube E 8500 Alt/Az Telescope mount

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I had to replace one of the Alt bearings in my Cube E mount (it was “grinding” and causing star trails at 1-5 second exposure times due to vibration).  I made a video of the procedure here:

https://www.youtube….h?v=TrKLkgV_WYM

 

The iOptron Cube E 8500 that I have uses 2 sizes of bearings:

 

1x   6804z bearing (20x32x7mm) for the Alt axle closest to the telescope.

3x  6803z bearings (17x26x5mm) for the ALT axle nearest the “lock” handscrew
and for both the top and bottom of the AZ axis in the bottom.

I purchased and used this NSK brand bearing.

You’ll also want a 14mm or 9/16th box end wrench to remove the AZ axis bolt head if you need to access the bottom.

Before/After results (click to enlarge):

Aftermarket Glowforge Hinge bracket installation

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I’ve had issues with the front handle and rear hinges separating from the glass lid of two different Glowforge units.  After repairing one side of the rear hinge that was separating I decided to try out an aftermarket hinge bracket designed to get a better connection between the glass lid and the two hinges.

I paid $160 with shipping to an eBay seller for item number 175473691329 “New GLOWFORGE Aftermarket LID Hinge Repair Bracket, All Metal Construction” which has a U-shaped channel to surround the rear edge of the glass lid.  It was a bolt on (and silicon sealant glue) procedure, and the hardest part was unsticking the double sided adhesive used to hold the glowforge lid ribbon cable in place.  [I ended up using dental floss to saw through the sealant behind the cable….when I replaced it I just used electrical tape to hold the cable in place.] I also had to spend some quality time removing the epoxy that I had used to initially repair it for a few months.

The procedure went smoothly, and the lid appears to be working (and sticking) well, although only time will tell for sure how much better this bracket is compared to the original one.

Sphero 2.0 battery replacement

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The original batteries in my (8-10 year old) Sphero 2.0 died.

bloating lipo lithium batteries
Once I got the sphere open and removed them, it was clear that they had “bloated”.
They are marked 702035 (7mm thick, 20mm wide, and 35mm long).  However, I don’t recommend buying 702035 batteries to replace them, as the opening they need to go into is closer to 30 or 32mm in length. If I had to do it again, I’d order these 702030 batteries instead.
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Reverse Bifocal Trick for Prescription Crafting Glasses

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I need optical magnification to work on small crafting projects. However, I also wear prescription lenses, so used a headband based magnifier that I could wear with my glasses. It worked fine, but I didn’t like having to wear two different things on my head, and the forehead mount was a little uncomfortable.

So, I’ve come up with a trick that allows you to order prescription glasses that include a magnifying inset lens. For those of you who wear bifocals…yes, I’m talking about bifocals. By turning the NV (Near Vision) field of a bifocal prescription as high as you can get it, you can get a magnifying bifocal insert of 1.87 X or greater.

The formula that relates optical magnification to dipolars is:

Magnification = (Dipolar / 4) + 1

So with the maximum +3.5 dipolar Near Vision (NV) setting allowed by Zenni Optical, I’m able to get prescription glasses that include a 1.87X magnification inset.

Of course, they are down near the bottom of the field of vision, which works OK for reading in your lap, but not as great if you paint with your elbows on the table like I do.


To move the magnifying areas from the bottom of the glasses to the top, you need to rotate the lenses 180 degrees, AND you need to swap the right and left lens. [So that the bifocal inserts are on the insides, and not moved to the outside of the lens…]

This means that when you ORDER the glasses you must REVERSE or SWAP the OS and OD (Left/Right eye) prescription lines!  Other than swapping for left/right eye, the cylinder and axis numbers don’t need to be changed, as the 180 degree rotation is a perfect no-operation for them!





You also need to order a lens and frame style that is perfectly symmetrical, so that you can fit the lenses back into the frames after you rotate and swap them. I recommend metal frames held together with screws, or rimless models where the lenses bolt directly to the frame pieces. (But watch the mounting holes for symmetry!) Round lenses are usually your best bet, but you could make it work with some of the hex or octagonal lens styles.

I used Rimless Glasses 3229415 from Zenni Optical. If you use my $5 “Refer a friend” link, you get $5 off, and I get $5 towards my next non-standard experimentation with optics (because this wasn’t my first order from Zenni…)

5$ off link: https://bit.ly/3LLPZCX

Alternatively, if you don’t want to hack your glasses, I recommend the headband based magnifier with light in this amazon affiliate link:
https://amzn.to/3xTWRIV

Total cost? This set of glasses only cost me $54 (now that I know what I’m doing) but I did waste another $50 for a different set of bifocals before realizing that the standard bifocal inset area was too low for my needs, and that I’d have to modify the prescription by swapping the left/right eye so that I could rotate and swap the lenses.

Here is a video about the procedure: