Category: FAIL

Sync Pulse of Horror

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Copied from where I wrote about it on Facebook…

Let me take a moment to tell a tale of horror. Sorry, I missed Halloween with this one….

The Evertz 7700ADA7: A wonderful piece of hardware. Truly wonderful, I have nothing but glowing things to say aboutAAAAHH HELL IT’S A PIECE OF CRAP.

https://evertz.com/products/7700ADA7

Look in its manual and you’ll see a big contradiction. The block diagram says it has buffers on every output. The text says it has three output buffers. In reality, best I can tell from physically inspecting the card, it has ONE and all the outputs are just paralleled… maybe in pairs or something? Look closely and you can see the ICs at the right where the outputs come off. Everything to the left of center or so on the card is the power conversion and fault detection circuitry.

The input can be set with 75 ohm termination onboard or hi-z. This is like the inputs on the old Grass Valley Group analog video DAs, except that those had a far more convenient setup with two BNC spigots on the back – you used it either as a loop thru (short BNC jumper to the next DA card in the frame if you needed more ouptuts) or popped a terminator on the unused one.

Evertz says you can use BNC tees to do the same thing on theirs, except… there’s no physical space for the tee to fit back there… and if you do somehow manage to physically connect the cards up this way it’s obvious their idea of “hi-Z” loads the line down BADLY after connecting two or three cards.

So, someone who came to that facility before me wired the cards with the black burst coming from the Evertz GPS locked sync generator and switch unit of HORRORS (more on this later!) to the input on the first of like six 7700ADA7’s, then a short jumper from output #7 to the input of the next… and so on…!!!

I mean, luckily, by some grace of Farnsworth’s ghost himself, this still managed to work… HOWEVER…

Please note that I said the outputs are not individually buffered.

The DA outputs were all full up when I had to connect a long cable to a new video playout system, except for one output on the first in the chain that went to some long abandoned weirdness halfway across the building.

I will state the following now that the statute of limitations is over and I am several thousand miles from anyone who would want to throw things at me for what happened.

We were in a newscast and a break was rolling at the time. I disconnected the mystery cable and there was no excitement. I connected the cable that went about 100′ over to the new playout system, and I heard screaming.

Apparently when I connected the new cable, a glitch occurred on the output of that DA, and since it had no buffers, it propagated down to all the others and effectively to every other piece of equipment in the plant. The people in the control room were treated to the sight of every source suddenly melting down and laaaazily reclocking and coming back one at a time.

At the same time, this lit the FU Cracker on each of our Ericsson satellite receivers. See, this model.. I think it was RX8400? … if you paid for a ton of extra option codes you got an internal frame sync/converter. This was EXTREMELY FRAGILE, though– if you caused any problem with the black burst sync, the FU Cracker’s 45 second fuse was now lit and there was not a thing you could do about it. Once the fuse burned down, BANG!!!! The video and audio were gone. It’d sometimes come back after an agonizing 15 seconds or so, but if it did, this would keep recurring until you rebooted the receiver.

You could practically hear the hissing.

Fortunately no sat feeds were used in the remainder of this newscast and I was able to go around and do the mass reboots once it ended.

So, as for that Evertz failover switch unit that fed the stack of DAs with blackburst… boyy that thing had a … failure mode… about it.

So the way that unit worked was it took the output of two independent GPS locked timecode generators that I think put out SMPTE timecode and trilevel sync. This fed into the failover box which would “seamlessly” take over if one of those went invalid or failed, I guess, and it also generated blackburst with VITC, had a small DA for the trilevel sync (4 ports or something), and also generated a 10 mhz reference signal and some other stuff I’ve long since forgotten.

The chief engineer needed trilevel sync for something near it, so he removed the terminator from one of the taps on that DA.

“Tick tick tick tick tick tick”, responded the failover unit.
Cue MASSIVE screaming from every corner of the facility. Bad sync hit HARD, all the satellite receivers puked their guts up instantly, just about the only thing that survived it was the Omneon playout boxes and the Kahuna switcher. No more live shots as the receivers decoding their ASI streams died. Yes, we were in a newscast. Recorded packages were frantically bumped up the schedule as the Omneons, Grass Valley K2 playout and cameras were the only thing left alive.

The Omneons and K2’s were really good about sync loss, if the sync went invalid they just switched to free running without any further ado. Everything else was just a fecking drama queen.

Oh no you didn’t

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Another PTek. Another questionable combiner. This one doesn’t even make any damn sense. I’m scared to open up the top of the transmitter to find out why it’s wired the way it is. The resistors are sitting on top of that hand cut piece of random PTFE and will cause a fire if they ever dissipate any significant energy. This is inside an FM2500PS transmitter.

Update: I added the horrible story below of why we have this thing.

This is a two port Wilkinson combiner that combines together the output of the left two pallets and the right two pallets. Why it’s floating on the thick PTFE slab, I cannot understand— these resistors appear to have the terminal configuration in which one lead of the resistor is the heatsinking base, and the other is the solder tab which just passes right through otherwise. WHY IS THIS BOTH INSULATED FROM AND ELECTRICALLY CONNECTED TO THE HEATSINK??!! Basically, what WILL cause this combiner to blow chunks would be any imbalance between the left and right sides of the transmitter – a single module failure will roast the entire rig. Catastrophically. See video below.

The lower line from each side goes to the start of the harmonic filter network, where they are just unceremoniously smashed together. This is… about the caliber of a badly built CB amp.

Dare I open the top and look around or have I suffered enough torture already??

(edit: yes… sadly I did!!!)

Page spam cut— click to continue. If you dare. I warned you, and Alex Hartman always warns ME not to open these transmitters and look around. But I do anyway. Then my brain hurts. ARGH

Read more “Oh no you didn’t”

On top of spaghetti, all covered in tape – the 2018 Ford F150.

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At work we have a rented F-150 to get up and down the mountains. I was going up to one of our sites, nearing the summit, when I smelled a burning plastic/rubber odor. I opened the hood (easier said than done– the placement of the safety latch is, to use my late uncle’s words, Kardashian) and found the cause after about a minute.

Behold….. Ford wiring.

So I’ve been under the hood of a few modern vehicles. All of them except this have the wiring harnesses protected by plastic tubing. This… uh, they just threw a lot of tape on it.

Interior: they used some kind of vinyl tape instead.

Weird shit.

The burning smell was a loose piece of tape from the harness on the right hanging down into the manifold. I removed it before taking the picture and buried it in the sand because it was actively on fire— it had glowing embers at the end.

What the fuck, Ford?

Incidentally I’m mad at this shitty truck already. It gave me a bloody nose. See, they put this weird aluminum roller in the seat belt buckles that serves only to make them insanely heavy. As I got out of the truck, the retractor brought it up at unnecessary speed to meet my face with an audible CLONK. I’ve seen the same buckles in Kia and FCA vehicles, but they are not anywhere near as heavy (the roller is hollow I guess). The roller makes no sense at all, it doesn’t turn and is loosely mounted. I’m guessing they did this to reduce wear on the fabric? Funny how my Subaru doesn’t have this and there are no signs of wear to the fabric so…. Uhhhh??

I could go on about how much I hate that steering wheel in the background but I’m out of shitposting juice

MicroREKT

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I always used to wonder why every time I worked in a radio site I’d find the transmission lines going through the entry panel just goobered in there with silicone sealant or spray foam and the unused pieces of the Microflect / Andrew / CommScope / insert today’s name of the conglomerate cable entry port system lying around unused

Now I understand why and my arms and hands and back and legs all hurt, hours later

Woop Woop the FUCK POINT has been reached, this is as good as I can get this one. You just can’t get these things together if the cable doesn’t wanna go through straight.

No!! You savages!!

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I’d seen these photos of the Mt. Shasta Mall food court….

But apparently someone thought it’d be a better idea to throw that beautiful thing down the grinder and cut it off with the blank wall of an Ulta Beauty store.

Even the Orange Julius is gone in favor of yet another SalmonellaWay.

Press F to pay respects.

The Subaru and Nissan brake light switch… Of DRAMA

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The contact that turns on the brake light, turns off cruise control, and triggers the solenoid that lets you shift out of park got all pitted! Ewww. Needless to say this was a show stopping bug… but it died at a gas station in walking distance of a Walmart where I was able to get some CRC QD cleaner and 2500 grit sandpaper and burnish it back to life. Here’s the before state. The contacts are actually proper silver buttons and the switch can be disassembled to clean it.

What a right mess though.

Not sure why the CRC QD cleaner turns my skin all weird looking like that.

The switch has a Nissan logo on it so I’m guessing some Nissan model out there in addition to the 2014-2017(?) Subaru Forester have the same thing.

PITAtek

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Upon having the strange experience that a new supposedly frequency agile PTek would only work on half the band (seemed almost like an exciter unlock or something when I tried to dial in 107.1?) I decided to look at the exciter card to see if there’s a tunable tank coil or something

I wish I hadn’t now

SCA and composite inputs, J9 and J10 respectively. C66 lowpasses the composite sorta by shunting everything above an unknown frequency to ground. C65 highpasses the SCA, it’s in series. The two combine at fixed yet frequency dependent levels and go down that via near C63 and R33. U7 under the board is a voltage regulator. J1 is the RF out and L1 is the DC feed to the power amplifier just out of frame.

Yeah just go right ahead and stuff the audio inputs right on top of the RF out. No big deal.

Full view of the card. The DDS is at upper left.

Think you can get away from having your audio run across the butt of a voltage regulator by using the XLR jacks? No.

The trace going down the via next to R81 is one of the audio channels, and it runs right under the header connector for power and data to the board.

A word on this PA. This is a new LDMOS transistor from ST Micro. As such, its dissipation is really low, and it basically gets heatsinked by the leads and traces. Here’s the reference design…

What you get is significantly less copper. The big ground planes that’d soak heat away via the source leads are just not there… so a weird block thing was sandwiched under the board and I don’t even want to look at this any more

The stereo generator used to, in earlier designs, be based off a DSP that I’d heard they couldn’t get anymore. This stereo generator is what I could best describe as “deconstructed BA1414 feeding a high speed ADC”. I’m guessing the two PICs are used for timing generation and the 8 bit ADC, U8 / DAC0800LCM is probably used to generate a sine wave from a lookup table or something. conspicuously absent is any sort of audio filter to roll off program content above 15-18 khz, if this is present the generator flips the hell out. It’s a living nightmare on green circuit board. Gaaah.

Side note– the BA1414 I mentioned above is a chip made by Rohm which is used in a lot of really cheap little FM transmitter baubles and produces TERRIBLE output. It performs stereo multiplexing using a couple of poorly filtered square wave oscillators that are mixed with audio.

Go ahead, change the oil. I dare you.

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This hilarious oversight found on an Allmand Maxi-Power 25 generator. The engine is a small turbodiesel utility engine made by Isuzu. The whole thing was assembled in Japan by Hokuetsu Industries….

… who hopefully sell a special bendy straw funnel.

Here’s the oil fill cap. The drain and filter are very easily accessible from the other side. But the filler… Oy!!

Above, the exhaust pipe.

Perhaps you can get in from the other side? …. Nope.

Look at that cute little tangerine sized turbocharger!

It seems to be like they could have added an access hatch above to make it easier, but yeah… Bring your Crazy Straws….

Target, what did you do??

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Newly remodeled store, just… nauseatingly confusing layout. Maybe all the fresh carpet adhesive smell is what’s nauseating though. Oh yes, it’s CARPETED, which will guarantee it reeks of filthy carpet after a few months, like a CVS store does.

Central Illuminated Sadness Cavern (TM)

Slotting fees are nothing new in retail. A company must essentially pay rent to a chain store in many cases to get their product on the shelf, and must pay more for certain features such as end cap displays, shelving at eye level, not having the store’s own generic of the product displayed next to it— in this case certain brands of kitchen products paid to not be plunged into DARKNESS. My visual estimate says 2 f/stops down when you go back to the wall. Amazing.

And this isn’t even one of the layouts with the new “River” concept, which is a curvy path from the entrance that will parade shoppers past promoted items…

Funny how this layout in particular reminds me of the one that took Sears to its grave. 😉