So here @ casa don there are two big ceiling fans. Casablanca Panama II 6645T models, each with a light kit. You can see what it looks like in the wild on the right.

Now, sadly, both have become ill. The one directly over my desk works ok, but after a few minutes the fan starts making a buzzing electrical noise.

The one in the photo, well, not so much action.



But even without these problems, there is a more basic one... The 'smarts' are some 80's era X10 style, with a wall-switch like this one. It operates wirelessly (I think using X10-style zero-crossing rather than radio). And this is nearly 2020, we should be able to run duke nukem 3d on a fan by now. Or at least crysis.

OK, so step one, ladder, screw driver, hex driver, dust removal (eww), and we are in. There is a control board sort of around the fan. There are 6 triacs (and 6 speeds.... hmmm... coincidence?), and a 'resistor pack' strapped down the side.




If we look in a bit more detail, there is a relay (DPDT) which I'm pretty sure is for the reverse. There is a 10uF capacitor which runs to one winding of the motor, and then the AC runs to the other winding through that resistor pack/triac setup.

Now, the most likely culprit for the noise is the capacitor. Capacitors fail over time, particularly when they are from '2nd tier' brands, as this one is. So i remove it and check with the meter. Interesting, the Yuchang 10mfd/250wvac shows 10.11 uF. But my meter doesn't measure ESR. Hmm. OK, i'm going to order two replacements from digikey. I picked the MMP2W10K-F, I hope its a decent match, i couldn't find a a datasheet on the Yuhchang site, this was the closest.

OK, so step one will be to see if the capacitor swap fixes the noise. But step two clearly has to be to get an IP address on this thing.

So here's where it breaks down as method. Method A, i do some retrofit. I add an ESP8266 to this circuit board. I have the ESP drive the same TRIAC (and sort out what the other switching transistors do, maybe related to the light-kit dimmer?). Method B, i ditch this circuit board, and get some logic-level triac to do the dimmer for the lights, switching to the existing resistor array for the fan (and keep the concept of the phase-shift capacitor/direction-relay as-is).

So... pro & con. If i go with the retrofit model, I get to keep the wall controls and have them coexist with the home automation/voice. If I go all new, well, i'll understand it all. What should I do gentle reader?

Oh yeah, and given the phase-shift capacitor checked out on the meter, what would you suggest if the buzzing/shorting noise persists after I swap it?

Retrofit and keep the wall-switch, or replace and screw the next home owner?

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OK, so here's the deal. The below pictured free-loader has been coming by my house for 4 years now. This is about the max distance you can get to him (presumed him because no kittens have been observed). If my door is left open, he'll come in and snoop around a bit, maybe play w/ some catnip toys.

That little house you see in the background (yes its heated in the winter!) is where he can hang out in the rain or snow.

The cat (called 'Outdoor Kitty' or 'OK') gets fed (and as a consequence so do the raccoons and squirrels). After 4 and change years, we are now at a ~3m relationship, as long as I pretend not to see him. So, question (and poll below), do I now have 2 cats? At what stage is a stray cat your 2nd (or 3rd? 4th?) cat?

When is a stray cat your cat?

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OK, some asked about 'what is bifurcation' from the previous post. Essentially, if you have a PCI-e x8 slot, you can split it in half and make it 2 x4 slots. If you have a x16, you can make it 1 x8 and 2x4, or 4x4.

You can see below, i've overlayed my BIOS setup on top of the motherboard diagram (here a SuperMicro x10DRi-LN4+). Now, if your BIOS doesn't have a bifurc option, you can possibly get it to do so by adding support into the BIOS. I'm not going to help you with this, its very complex, but I was able to add both UEFI NVME boot and bifurcation to a different SuperMicro motherboard by adding the UEFI modules into it manually. YMMV. Void where prohibited.

So in my case, I have a NVME carrier which is capable of holding 4 NVME drives. It is passive (no PCI bridge is onboard). This means that it is conceptually 4 PCI-E x4 drives. Without bifurcation, it just won't work. Some people refer to this as 'pci splitting'. You may see references to this in the 'crypto-mining' industry, where people are using 1x interfaces via cables to mining ASIC.

Be careful here, bifurcation is supported on server motherboards with modern chipsets, but its support on desktops is not as universal. And just because your motherboard supports it doesn't mean your BIOS will.

It may also have downstream affects on other PCI-e cards, e.g. reducing their lane-width. Caveat Emptor.

Earlier I wrote about selecting the Asus m.2 x16, a 4x NVME carrier, each with PCI-E x4. It arrived, i installed. The reason I chose this one is that a) my motherboard supports bifurcation, and b) my NVME cards were 22110 (with integral capacitors for write flush on power-loss). As you can see from the photo, i shorted the head-pad a bit because of the extra height of the capacitors.

If you are looking for a great deal on a lot of fast storage, check out the ebay listing. Or even some other online listings. @ $270/TB of fast NVME, how could you go wrong? Chuck your sata to the curb and join the revolution.

My living room TV is driven by a Vorke Z1, (and an ExpressVU Satellite box, and a Chromecast, and, ... but this story is about the Vorke).

The Vorke runs Android (7.1.2) and Plex, and connects to the basement NAS (which runs the Plex server). And it has worked pretty well for the last 9 months or so, its fast, integrated easily w/ the harmony remote, and just works.

Well, no more. I got home Saturday night and the user interface of Plex is all 'new', news, etc. Huh. But, more interestingly, there is now the Android status bar on top of it all. And, since the TV is plasma, that is burn-in material (as well as an OCD OSD distraction!).

Interestingly in the settings there is no longer "TV Mode" versus "Tablet Mode". It just 'knows'. OK, i can fix this right? Well, it was trickier than I thought. See, the Vorke, unlike the rest of the stuff inhabiting my house, had not been rooted. OK, time to fix that. Oh, erg, ack, the image is a u-boot bootable OR you put twrp on a sd-card and go. Well, lets do the latter. OK, shortly after that I am staring at my new brick. Hmmm. Why no love?

OK, well, lets sort out how to unbrick this. The screen just says Vorke, it has only 1 button, so try that various ways (before power, during power, after power), but no recovery greats me. OK, time to roll up sleeves. a bootable u-boot sdcard, how hard can that be to make in Linux?

Well, not very. There's some windows program that floats around the russian 4pda site, but i'm not over keen on that. So what if we extract the u-boot from the image file and then dd it to the sd-card? First, lets unpack the img file. A little google-fu led me here. And then I installed 'android-libsparse-dev'. And then added -I/usr/include/android. And then I had a binary. (This code works too).

After that, I unpacked the file, which yielded aml_sdc_burn.UBOOT and aml_sdc_burn.ini.

I then took an (micro) sdcard. I used fdisk to partition it, and made the first partition start @ 8192 (instead of the recommended 2048). I made it type 'c' (W95 FAT32). I then did a mkfs.vfat on the partition (/dev/sdd1 for me).

I then did:

dd if=aml_sdc_burn.UBOOT of=/dev/sdd1 bs=1 count=442
dd if=aml_sdc_burn.UBOOT of=/dev/sdd1 seek=1 skip=1 bs=512
cp aml_sdc_burn.UBOOT /mnt/sdcard
cp aml_sdc_burn.ini /mnt/sdcard
cp vorke.img /mnt/sdcard/aml_upgrade_package.img

where vorke.img is the original not-yet-unpacked.

I then put the sdcard in, held the reset switch as i applied power, waited about 3 seconds, and it started to upgrade, and it worked!

(and of course I picked a rooted img, but you can easily put it in there yourself).

Once complete, I'm unbricked. I then pick one of the (fairly crappy) apps from the play store that get rid of the status bar on a rooted system, and I'm good to go.