Snap, Crackle, Pop! Triax Crispies.

I’ve always found the old school triax connections used for some studio cameras….. charming. Triaxial cable looks mostly like a RG-6-ish coax with another dielectric layer and another braid over it, with the end result looking a bit more like RG-11… until you see the freaking WEIRD connector it terminates into. It’s like a ginormous shell around a BNC. Trust me when I say you do not want to be coiling this cable up and have the connector fly over and smack you in the— uhhh— output spigot and terminating resistor. OW. But anyway—

Cameras hooked up by triax can be powered over the triax. To do so, the Camera Control Unit (CCU) sends a high voltage – 120-170 vdc I think, down the cable, between the outer and inner braids. A DC/DC converter inside the camera powers it and any ancillary equipment like lights hooked up to the 12v output it provides. It works great, but you MUST ensure that the voltage has been removed from the cable before unplugging it. On some systems, it seems like powering down the camera tells the CCU to stop sending that voltage (or it drops to just a few volts – just enough for it to power whatever onboard the camera tells the CCU that the cam is connected and requesting to be powered up?). Anyway— at my old station I had a few instances where someone would unplug the cable hot and it would make the camera mad or even carbon-track the plastic inside the connector.

Today I found out what happens if the cable ITSELF gets angry:

tri-axial foaming cable

From top to bottom: The outer jacket with subtle black mark from the fault within, the middle dielectric and inner braid, and the outer braid, which frayed then burned in half at the fault location.

The ridges are from the connector’s strain relief. This fault occurred right behind the connector, where the cable was getting flexed a lot.

The CCU reported the cable was shorted out, and this was confirmed by a resistance reading of about .15 ohm at the connector on that end as measured by the onboard multimeter on a Tektronix 2236

All three elements of the cable – the center conductor, inner braid, and outer braid were shorted together.

I was able to lop off the end of the cable and remake the connector. The connectors we had in stock were circa 1996 and were made by Kings about, oh, two corporate umbrellas ago. Currently they’re under Winchester Interconnect and Winchester has no documentation on the connector including what the strip lengths are for the layers of the underlying cable. Canare and Cinch have different takes on the same thing. I managed to get it back together with new parts for the center.


The center is pretty much a crimp type BNC. Not shown, the….. ridiculous oldschool clamp thing used to hold the outer braid to the connector body, nor the giant ball-bonker connector body itself.


Not sure if it’s the world’s most perfect installation, but hey, it passed the Smoke Test and the camera’s back up on it and in service.

So spell out “I M A G E Lightbulb”…

Hey look, there’s a CYX bulb…..

And it’s terrifying

The pins are about 3/8″ diameter and the whole bulb is 8 1/4 inches high overall with the light output centered 5″ above the bottom. It has an average life of 300 hours. The normal application has it inside a Mr. McLargeHuge stage fresnel safely locked away behind a big thick glass lens and a metal screen. I don’t even want to think about it too hard.

For a small $945 you can get a VisionSmith ReLamp module that lets you replace it with a 275 watt LED that pays for itself *rapidly* in reduced air conditioning and power costs…

Discontentment at RF Central

Several years ago, I worked for a TV station in Miami that had gotten a bunch of Eurotek microwave STL and ENG link radio units out of the Sprint/Nextel MMDS rebanding deal. Apparently, at the time, Sprint’s tradeoff to get the spectrum was that they had to provide new 2 ghz microwave ENG gear to any TV station whose stuff would have been obsoleted by the new bandplan. Some stations got a different one, others got the Eurotrash, I mean, Eurotek.

We had quite a few of them, all in relatively non-critical service. One of our older engineers there was trying to keep them all alive but his success was limited as the 2 ghz and particularly the 7 ghz units liked to lose reference oscillators which were made of pure Unobtainium.

The units had constant cooling issues that led to a lot of power supply and amplifier failures too.

I mean, don’t get me wrong, it was a kinda cool platform for its time… all modular and a 1U mainframe could contain any mix of transmitters (upconverters), receivers (downconverters), power amplifiers, ASI stream multiplexers or demultiplexers, and can even interleave general purpose data over the connection and make it available via standard Ethernet ports on either end.

Unfortunately it’s about like most other Italian RF gear I’ve worked on, which is to say……. questionable garbage.

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Bok-AWWW, Sacramento

I heard some happy crowing in the studio this morning and went to investigate.

“Sir, are you aware you’re a rooster?”

S H 🐣 🐣 K

Yeti the rooster and Patty the duck were wonderful guests and gave us all plenty of happy butt wiggles and little chirps.

420 smoke semiconductors every day

Did I ever mention that I’m glad I don’t have any Screen Service rigs in my care?

These RF Central ENG microwave rigs are quite enough thank you!

I dunno, Italian transmitters aren’t my cup of tea, but at least they’re leaps and bounds better than PissTek. 😉

/!\ DANGER: THIS POST CONTAINS COMIC SANS /!\



This dumb thing has never once inspired any confidence in me, between the choice of font on its GUI (various old Harris / Leitch products are infected with Comic Sans including whatever this was based on) and the fact that it ROUTINELY makes one of our stations fail to black and has to be bypassed out brutally with a patch cable and whacked in the face with a large trout with great vigor until it reboots. As an added bonus, the setup / diagnostic screens do not work, you instead get a big fat flash of “Not Available” in Comic Sans.

 

this inspires about as much confidence as it should (none at all)

also wordpress literally reverted automatically to the default style and will not allow me to type more than one block of text in Comic Sans and this is probably very much for the better ok

At least the actual keyer card (as unstable as it is) presents a tiny bit of data via a… perplexing, tiny, graphic VFD display on the module edge. Why a VFD here? At least it’s not an OLED that goes unreadable after a year.

ok that’s enough comic sans now i’m gonna go wash my eyes out with tape head cleaner

 

The best testimonial I’ve ever seen

From a fellow engineer:

Our guys were so impressed with the Selenio at our sister station that as the NetVX aged into backup status, we bought a Harmonic.

selenio shitpost
sorry, I only have M$ Paint on this workstation and it’s fairly useless for proper shitposting

 

For the uninitiated— what this unit does in its most common configuration in a TV station is it takes in one or more audio/video inputs, encodes them to MPEG-2 program streams for digital television, and finally sends the output out as an ASI stream. An ASI stream is a combined feed of all of the subchannels to be sent over the air plus the metadata (PSIP), and is what is actually modulated and sent out by the transmitter. The PSIP is used as an index by your receiver and populates both the channel definitions and the program/station info that gets displayed in the program guide. That being said, it is the house of cards upon which your entire station is delicately balanced. 😉

In all seriousness, this is one of the strangest, most fragile, and most inherently unsupportable pieces of hardware I’ve ever worked with. The UI from which you have to perform most configuration tasks is based on Microsoft Silverlight, which is a dead-ass format M$ came up with to compete with Flash, which is also a dead-ass format. Double-dead-ass? I dunno. It’s pretty awful and soon I predict that’ll require us to keep some old computer around with an EoL version of Windows and Silverlight installed and no auto updates allowed because M$ will just decide to flush Silverlight away entirely.

There’s also a telnet interface into the thing for which there’s little documentation. Certain configuration tasks (which is to say most of them) require a call in to Imagine Communications support because it’s just… well, at least one person who worked on the software knows how it works, right?

The hardware design is kinda questionable and the firmware hocks up hairballs for no good reason. So far across the three of these I’ve worked with, I’ve experienced phantom frame controller failures, A/V desync, audio loss, video loss, video freeze, video macroblocking, unreported loss of ASI output with invalid picture input, reported loss of ASI output with valid inputs, and one that just plain powered off and restarted during the evening news. Oh, and you see that little display on the front? It CAN display useful status information, but…. doesn’t. Also, Imagine Communications’ idea of a “screen saver” for the little OLED screen is to display “Imagine Communications” on the top line, unmoving, forever… so when you try to view any status/fault info, you’re reading it through a permanent shadow of “Imagine Communications” that’s practically CHISELED into the matrix. Ew.

 

How to stir the pot with bad statistics

This one TV station keeps posting news stories about InSANeLy HiGh gAs PriCeS!!!LOL to Facebook and it stirs people up.

Each time they’re going on about $5+ gas.

Each time, they are using a Chevron station somewhere as an example, and I’m guessing they’re using one near the rental car return at LAX.

You know…. That One Station That’s Always A Couple Dollars High.

Here’s an example from the comments:

It is also worth noting that Chevron is usually more expensive than other brands.

Yeah, uh….

No