One bad gloop and she do what I yoinky

Crooooooooow!

Ever seen a TV live truck on scene? Well, if you have, chances are you’ve noticed a thing on top that looks like the top of Crow T. Robot’s head on a tall extendable mast.

What you’re looking at is a foldable microwave dish that can be used to send video from a live shot back to a fixed receiver site that forwards it to the TV studio. At the bottom of it is a remote controlled pair of big chonky motors that let you, standing on the ground, pan or tilt the dish to get it lined up with the receive site so the station can see your live shot coming in.

 

One of ours got stuck in the up position so I needed to pull it apart and fix it and I intended to take some more pictures of the apparatus as it’s kinda cute – it has two big Bodine gear motors driving worm screw drives via little drive chains, and has limit switch cam assemblies to keep you from going past safe travel limits on the thing.

I found the issue pretty soon after figuring out how to open the weird chassis of the dish motor, which opened vaguely like a milk carton – a hinged milk carton made of sheet metal. I’ve never seen anything quite like that and have to give them points for originality, though, if you had to get in there and the dish was stuck in a position other than straight up, you’d have to disassemble the entire shebang from the sides and take the dish off and everything and eww.

Thankfully, this was stuck straight up, and Tina caught a couple pictures of me working on it after I got it open:


But then the gloop went off.

See, what happened was one of the motor brushes got stuck in the brush holder and wouldn’t advance as it wore down a little, which caused the motor to stop working open circuit. I pulled it apart and managed to get this picture before I realized….. whoops, the armature of the motor and its pressed on bearing were the only thing holding the gloop in. You can see the brush on the right still wedged back in the holder where it can’t actually touch the commutator:



The gloop I refer to is a particularly foul, stinky, sticky, syrupy sort of gear oil, almost all the way up to being a grease in viscosity, but just low enough in viscosity to allow it to make a huge mess in short order. This is the second time I’ve run into it on Bodine motors – there’s no externally visible sign of it having an oil filled gearbox, no fill/drain screw or plug, nothing. You just get a terrible surprise if you dare separate the motor from the gearbox. GLOOOOP.



A fair amount escaped and got all over everything, but there was certainly enough left in the gearbox immersing its guts that I don’t feel I need to disassemble the whole thing and try to refill it. Nah, it’s just a learning experience… AGAIN…. BEWARE THE GLOOP.

Otherwise it will get the song stuck in your head. That song never leaves…. not that it ever has to.

There’s an extended version too

Fontabulous

Just when you least expect it, what’s basically a portable scalar network analyzer starts talking to you in THIS FONT and you start disbelieving your own eyes:

Wonder if that’s from that Microsoft core fonts package that they made freely available years ago then pretended they didn’t
Oh by the way the antenna is …. Uh. It’s… not?

Root cause of that scary looking reflect plot was revealed by a quick walk up the stairs to the roof to be an almost completely disintegrated piece of LMR-400. My coworker assured me it worked perfectly fine five years ago……..

This post brought to you by the Premium Grade No-Pass Filter

This is several kilobucks worth of hardware that was misapplied to create a special filter that…. nothing would pass. See if you can spot the issue!

Our IT director dropped a non working Wyse serial terminal on my bench. I don’t think he expected me to tear it open and try to fix it, I think it has an open diode or bad cap in the +5v supply. It’s gonna be the serial console for a Linux machine if I can get it glowing.

And then I was asked to come on Good Day, pose dramatically on a giant shoe, and discuss the a ridiculous goth house. Just because.

Useful cybergoth meme
Kittie was so boss
No U

This has been a elliptically polarized shitpost.

visualizing data, irritatingly

Which looks sillier to an uninitiated observer, the results of this butt-dial Google search or my mess of a DMR radio codeplug?

In other news, buzzard puke alert! Changing the “Radio IP Address” field in Motorola TRBO CPS is not how you change the repeater’s Ethernet IP, it’s just how you get it to throw blank error messages with no explanation. Well that’s a solid block of fnord.

You wanted actual pixels? (Panasonic BT-S901YN)

Well, if you look up the brochure for this thing they say up to 300 lines resolution…

Thing’s so fuzzy when I first plugged it in I thought it needed a focus adjustment. No… It just needs…… actual resolution.

Seriously, what were you thinking, Panasonic? I’ve got dank memes with more pixels than this.

How many people came away from using these monitors with a lifetime of eyestrain?

this is our solution

This got pretty badly stuck in my head yesterday for…. reasons

I figured out the root cause of the issue I posted about earlier on with the crazy fan circuit…. waaaait for it:

The pin was never securely inserted and latched into the housing of the fan connector! Welp. Lacking the correct tooling for this connector series (I have yet to be able to identify it!) I broke the rounded end off one of those plastic stirrer sticks from Starbucks and used it to prod the thing into place. It snapped in and I plugged the fan in and it’s happy again. Speaking of fans and drama, this greeted me with a rhythmic pounding noise from the office roof yesterday morning. I sent the HVAC contractor a photo of it and he arrived at the door at 9 AM laughing with a replacement propeller in hand. The cause of this one appeared to be that the “belly band” mounting Trane uses for the fan allowed it to slip down.

By design, these Trane units have a behavior that I consider to be just this side of “broken by design”. When the thermostat calls for cooling, the compressor starts and pumps gas (R-410A in this case) into the condenser, where it gives up heat into the metal finned tubes, condenses into liquid, and is sent to the output lines and into the building to boil inside the evaporator coil, cool the air down there, and come back to the outdoor unit as gas… the usual vapor compression refrigeration cycle. As the condenser heats up, the gas head pressure leaving the condenser starts to rise due to thermal expansion. You can hear the sound the compressor makes change as the head pressure rises, and I’m guessing the motor current starts climbing too. Once it rises to a certain point, a pressure switch trips and starts the fan, which cycles on and off based on the head pressure.

This causes it, in practice, to cycle in about 5-10 second intervals, repeatedly flexing and stressing every part of the nasty stamped sheet metal assembly up there.

The first time I encountered a unit like this in the wild, I thought I was hearing it repeatedly overheating and tripping a safety cutout. I had to ask an HVAC contractor if that’s normal. They said that (sadly) it is. Why?! I guess it might save a LITTLE power, but I don’t think it’s worth the reliability problems.

On a side note, my parents’ house had some ancient Sears “Good Neighbor” condensing unit that was made by Whirlpool, part of a retrofit from the 1970s or so (best I can find from trying to Google the thing). It claimed to be a two-speed condenser, but in reality, was a single speed compressor paired to a two speed fan that’d switch between high and low as needed based on the compressor discharge line temperature/pressure. It never outright STOPPED if the compressor was on. Yes, this was done… better… over four decades ago. Sigh.

It may be worth noting this was a pretty small R-12 system, couldn’t really fight the Florida heat well, but lasted a LOOOONG time. The condensing coil was much smaller than it is on modern high efficiency systems and I remember the temperature of the air coming out of that condenser being fearsome. You couldn’t comfortably touch the top of the unit after it’d been running.